Ask an Engineer

[bogan]

For all those little questions that pop up when modifying motorbikes...

[Mental Trousers]

You might like to get this dude (http://www.kiwibiker.co.nz/forums/entry.php/2623-Mobile-Welder) involved as well as a few others like Ocean1 etc.

[bogan]

I'll go first, I'm doing some single point spline broaching (into ali), and have to grind up the broach tool as the hole size is about 8mm (gear shifter shaft). What material is best to grind into shape, and what grinding procedures (cooling etc) are needed. Have got plenty of busted carbide and HSS cutters if either of those materials would be suitable?

[bogan]

You might like to get this dude (http://www.kiwibiker.co.nz/forums/entry.php/2623-Mobile-Welder) involved as well as a few others like Ocean-1 etc.

Yeh Ocean1 would be right up there, I figure with one thread to subscribe to, all the good/helpful engineers can much more easily keep tabs on the smaller issues.

[Akzle]

I'll go first, I'm doing some single point spline broaching (into ali), and have to grind up the broach tool as the hole size is about 8mm (gear shifter shaft). What material is best to grind into shape, and what grinding procedures (cooling etc) are needed. Have got plenty of busted carbide and HSS cutters if either of those materials would be suitable?

ali is soft, so anything harder. carbide / HSS are brittle, not so good under a press.
ideally something pre-splined. i can't think of anything 8mm pre-splined.
get some 8mm mild steel bar, get busy with needle file (or mill and rotary-indexing table if u have),
then case harden it.

-edit-
hang ten. get an old gear shifter shaft! (+ harden, either by quench, or furnace/case, as above)

[Ocean1]

I'll go first, I'm doing some single point spline broaching (into ali), and have to grind up the broach tool as the hole size is about 6mm (gear shifter shaft). What material is best to grind into shape, and what grinding procedures (cooling etc) are needed. Have got plenty of busted carbide and HSS cutters if either of those materials would be suitable?

HSS is fine, and much easier to work than carbide.

You can try to do it in one pass per tooth, in which case you can grind a HSS drill down to the root dia, leaving a ring which is then ground to the tooth profile. Leave maybe 20mm at root dia before and after a 5mm ring. If you're taking it as easy as you should be you should get away without coolant but if you're doing it in the lathe it's just as easy to use the same soluable oil that uses. Need maybe 3-5 deg clearance and 15 to 20 deg top rake. What grinding gear do you have for that? For broaching I'd just do that in the lathe too, you can mark up the chuck to whatever No teeth you need and use a wire pointer in a DTI base. I use prolan as a cutting lube for high tip load work in alloy.

If that don't work you can make a smaller tool and take multiple cuts, with or without a support bush.

[bogan]

HSS is fine, and much easier to work than carbide.

You can try to do it in one pass per tooth, in which case you can grind a HSS drill down to the root dia, leaving a ring which is then ground to the tooth profile. Leave maybe 20mm at root dia before and after a 5mm ring. If you're taking it as easy as you should be you should get away without coolant but if you're doing it in the lathe it's just as easy to use the same soluable oil that uses. Need maybe 3-5 deg clearance and 15 to 20 deg top rake. What grinding gear do you have for that? For broaching I'd just do that in the lathe too, you can mark up the chuck to whatever No teeth you need and use a wire pointer in a DTI base. I use prolan as a cutting lube for high tip load work in alloy.

If that don't work you can make a smaller tool and take multiple cuts, with or without a support bush.

Hadn't thought of doing in a lathe...

Whats the 3-5deg clearance relate to? Is it part of the spline profile?

I'm doing this mainly as a demo project for work, so it'll be a little vertical shaper type setup with a rotary table. Probably CNC it if we find much use for it. Either way multi pass will be easy enough.

We have a tool grinder (http://machineryhouse.co.nz/G1975), but some bastard lost all the collets for it, can make something up for it though. No tool post grinder... yet.

[Ocean1]

Whats the 3-5deg clearance relate to? Is it part of the spline profile?

No, angular clearance between the faces trailing the cutting edge and the cut profile. Sharpening a drill the face you grind needs the trailing edge to be clear of the cutting edge, yes? That angle should normally be 3-5 deg. Top rake for alloy should usually be quite high.


I'm doing this mainly as a demo project for work, so it'll be a little vertical shaper type setup with a rotary table. Probably CNC it if we find much use for it. Either way multi pass will be easy enough.

Cool. Shapers are almost a lost art. I did my time on a fckung massive planer, fond memories of making swarf 1/2" wide x 2 thou thick x 8 ft long.


We have a tool grinder (http://machineryhouse.co.nz/G1975), but some bastard lost all the collets for it, can make something up for it though. No tool post grinder... yet.

That's actually a bit tempting...

[bogan]

ah, now I get it :yes:

Yeh often machines built for specific purposes end up being pretty neat. :shit: and here I thought the 5mm wide .15mm tick 300mm long swarf we were getting from the copy mill was a big bit.

Its not a bad wee unit, takes a bit to set up, but seems to have good precision. Not that it really gets used at all, we just buy whatever cutter is required, been able to source something for everything until now.

[Ocean1]

:shit: and here I thought the 5mm wide .15mm tick 300mm long swarf we were getting from the copy mill was a big bit.


Prob a slight exageration, certainly well over 2M long. The swarf ribbon was 3-4" shorter than the workpiece, was 316 and if you looked too closely you'd bleed.

[Padmei]

How much would it be to get a stainless brake disc made up? They can't be too hard to cut out would they?

How are they attached - rivetted? Can that be done in the shed or is it a specialist operation?

[Ocean1]

How much would it be to get a stainless brake disc made up? They can't be too hard to cut out would they?

How are they attached - rivetted? Can that be done in the shed or is it a specialist operation?

Cost about $20 of laser or waterjet time, but the alloy normally used isn't what you might call "off the shelf".
You could try calling Sandvik, they might at least be able to tell you what it is, but even if it's available locally you're probably up for at least one sheet.



Don't ask.

[Kickaha]

Cost about $20 of laser or waterjet time, but the alloy normally used isn't what you might call "off the shelf".
You could try calling Sandvik, they might at least be able to tell you what it is, but even if it's available locally you're probably up for at least one sheet.

Don't ask.

I had a guy do the design and then give it Sandvik to cut, it worked out somewhere between $300-400

[Ocean1]

I had a guy do the design and then give it Sandvik to cut, it worked out somewhere between $300-400

Well there y'go. Did you recall what the alloy is?

[Kickaha]

Well there y'go. Did you recall what the alloy is?

No sorry, if you pm Marsheng on here he might know as he organised it

[carburator]

single point broaching a lathe is a quick and dirty way of getting ones ass out of a hole and also very effective.

you can do the same in a mill with a rotary table with less hassles ( powering the table up and down is cheating )
HSS is fine, just take you time with the tool grinder ( or if you have a water pump drown the bugger )
otherwise couple of passes and leave, don't get color run though in your application whats a couple of rockwells..

generally we have worked out number of splines then ground a three point ( triangular broach end on ) to provide
full support or equal stress to stop the little buggers from wandering off... genrally we also stick a lead on them
and provide a decent releif area for swarf to curl up in ( and a cutting edge )

[bogan]

A painting question this time, I do a bit of cosmetic milling, which often involves graphics set into the part by a mm or so. I want the graphics to stay as a metal finish while I paint the rest, can I fill that area in with something fluid like wax to mask it off for painting?

[Ocean1]

Dunno. The only time I've done it I just scraped the paint out with wee toolmaker's files.

What I have done is waterjet cut graphics from 2mm sheet and epoxyd them to the housing for a positive relief effect.

Well, I was positively relieved after the earlier effort.



Sorry.

[AllanB]

Would you not paint first them cut the graphics in?

[bogan]

Could do, but it means setting up the work again, and the finish on the bottom of the cut need a polish anyway, which is easier to do without worrying about taking paint off the rest of it, and probably a similar amount of work as removing paint anyway.

[BASS-TREBLE]

Why not paint it with a roller? It works as long as you don't drown the roller with paint to the point where it drips into the cavity

[nodrog]

A painting question this time, I do a bit of cosmetic milling, which often involves graphics set into the part by a mm or so. I want the graphics to stay as a metal finish while I paint the rest, can I fill that area in with something fluid like wax to mask it off for painting?

Fill it with plasticine or bluetac, then just blow it out with compressed air after paint is dry.

[bogan]

Quick question re greased bushing materials, aluminium on steel is better than aluminium on aluminium right? This one is for a rear brake torsion bar, so no force when it moves (only moves when you adjust the chain/wheel/brake position), but plenty of force when stationary.

What about galv pipe, better to have it on steel or aluminium? and if steel, is it by much? This is for a cart, approx 200kg load through 4 wheels on 2 40mm galv pipe axles, expected to move less than 100m per year.

Both of them are low speed low use applications so not worth doing bearings or bronze. In other news, I turned up a very nice 60x90x80 bush for the vertical spline shaper out of bronze last week, cuts bloody nice, but hot chips everywhere!

[Ocean1]

Quick question re greased bushing materials, aluminium on steel is better than aluminium on aluminium right? This one is for a rear brake torsion bar, so no force when it moves (only moves when you adjust the chain/wheel/brake position), but plenty of force when stationary.

What about galv pipe, better to have it on steel or aluminium? and if steel, is it by much? This is for a cart, approx 200kg load through 4 wheels on 2 40mm galv pipe axles, expected to move less than 100m per year.

Both of them are low speed low use applications so not worth doing bearings or bronze. In other news, I turned up a very nice 60x90x80 bush for the vertical spline shaper out of bronze last week, cuts bloody nice, but hot chips everywhere!

Yes.

General rule for bushes is no longer than 1.5 x dia, material almost doesn't matter for that duty but consider cast iron on galv pipe. Worth noting that some materials cold weld, aluminium on aluminium will. The zincon pipe is OK, but make sure it's reasonably cylindrical and keep clearances around 0.05dia.

Yes, bronze makes for little sharp fuckers down your shirt. What bronze?

[bogan]

Yes.

General rule for bushes is no longer than 1.5 x dia, material almost doesn't matter for that duty but consider cast iron on galv pipe. Worth noting that some materials cold weld, aluminium on aluminium will. The zincon pipe is OK, but make sure it's reasonably cylindrical and keep clearances around 0.05dia.

Yes, bronze makes for little sharp fuckers down your shirt. What bronze?

Thanks, not sure what bronze, just found it in the corner of the workshop, and it was the perfect size...

[bogan]

Question about fire extinguishers, my insurance says I have to get one for the shed and it needs to be serviced yearly, does that mean I have to buy one with a service contract? or just take any old one in to get serviced?

Any recommendations on places/types/brands?

[Akzle]

recommend steer clear of bunnings 1lt specials.

your insurance company should be able to specify minimum requirements. for vehicles it is class B 1.5kg, sometimes two of, depending what you plan on driving into.

for practically putting out a fire, you're probably going to want a powder one (class B) although, depending on what's more likely to catch fire, a co2 may suit. (and doesn't make a helluva mess)

and probably a 3kg+ size. needs to be mounted with easy access on an exit route. (bench height by the door, normally)

"servicing" can be done at anywhere that services em, on any extinguisher. phone your local fire station to find place local to you.

[Ocean1]

Question about fire extinguishers, my insurance says I have to get one for the shed and it needs to be serviced yearly, does that mean I have to buy one with a service contract? or just take any old one in to get serviced?

Any recommendations on places/types/brands?

Does the insurance company specify what type of extinguisher or are they just padding the contract with escape clauses?

Either way you don't have to buy a service contract, but if they're calling for an annual service it has to be done by a "qualified person". Be aware that there's lots of them driving around looking for work, offering to check your extinguishers free and service them cheaply, (just sign here, sir). I know of one warehouse that was signed up to three different contracts, and unsurprisingly the service agents had completely ignored each others tags, in some cases refilling extinguishers last filled a month ago.

Type of extinguisher depends on likely use but in most workshops I'd expect to see ABE dry powder items. As for price, no real suggestions, walk the fingers.

[BoristheBiter]

[COLOR="#139922"]
ali is soft, so anything harder. carbide / HSS are brittle, not so good under a press.
ideally something pre-splined. i can't think of anything 8mm pre-splined.
get some 8mm mild steel bar, get busy with needle file (or mill and rotary-indexing table if u have),
then case harden it.


That's why most are made from HSS.
What a nob end.

[husaberg]

Right not everyone knows this but all the late era MV Augustas (the Real MV's that finished in the 1970's) actually had aluminium alloy disk brake rotors.
I know many have experimented with plated and plasma coated aluminium alloy disk rotors without success.

MV supposedly had no trouble with the plain aluminum alloy rotors but what alloy might they have used and what sort of pad material would be suitable.

yes i realise an MMC material would be probably better but does anyone have any ideas?
I are picking that it would have to had a high silicon content....

[Ocean1]

yes i realise an MMC material would be probably better but does anyone have any ideas?

No.

Other than to suggest the 7000 series cast tooling grade alloys are most stable both mechanicaly and thermally.

Guess annodising would add wear resistance, but it's not very thick. Wonder if the ceramic coating used on zorsts would stay bonded to alloy.

With enough cash you could play with explosive clad composites like toolsteel/alloy/toolsteel. Even then I'd think you'd have trouble keeping them bonded.


PS: if you've got plenty of cash let me know.

PPS: Have talked to NZ cylinders about chrome alloy disks?

[husaberg]

No.

Other than to suggest the 7000 series cast tooling grade alloys are most stable both mechanicaly and thermally.

Guess annodising would add wear resistance, but it's not very thick. Wonder if the ceramic coating used on zorsts would stay bonded to alloy.

With enough cash you could play with explosive clad composites like toolsteel/alloy/toolsteel. Even then I'd think you'd have trouble keeping them bonded.


PS: if you've got plenty of cash let me know.

PPS: Have talked to NZ cylinders about chrome alloy disks?

Hello Thanks

I guess MV being in the business of building aeronautics would have had some pretty exotic alloys and coating available as well as a large pot of cash. but any idea on a pad material for a aluminum disk?

all the stuff i have seen has said all the coating were not that successful i know Triumph tried plating with plasma and some other metal sprays. anodizing i think would too soon abraide off.
Def no to ther nicosil the plating. As already will be gifting them about $500 i guess for the cylinder so not relaly an option.

ps if i had plenty of cash i would be off to Monacco .......

Actually how big are some of those diesel pistons say a 140mm cat piston....... they would be full of silicon be heat resistant and i guess that is what burt would have used (if he had of believed in brakes that is) and second hand free......

[Ocean1]

but any idea on a pad material for a aluminum disk?

No mate, outside my experience. Guess whatever it is you'de want to make a good radius on the leading edge to help prevent it machining the disk for you.


Actually how big are some of those diesel pistons .

Fucking big. My old tutor used to tell us about standing on his ship's piston to clean up the ring step on the cylinder, with a disk grinder.


As for Burt, dunno if he made Indian pistons out of them but he definitely had a few Cat pistons donated.

[husaberg]

From memory (out of George Beggs book)the rod were Cat Grader axles hammered flat with a power hammer after been reheated in a forge
Initially he used Ford Truck axels but they were not up to the job.
The pistons were initially a mix of ford and chev pistons (as in the movie) but the gudgeon's were always ford
The later Pistons were die cast from diesel pistons as he assumed they would have to be better quality than the petrol ones due to the higher pressures.
He however always used genuine Indian roller due to the radius edges which he reckon were les likely to shed there hadending.
these were heavily worked as it was very late in the piece that he actually converted to a pressure fed big end.He said it was to hard (which is funny considering the other modifications he made which were far more involved)
The majority of the time the crankpin he used was only 20mm which to me is is amazing.


The piston idea may be worth a crack....
but i suspect there with be a bit of steel reinforcing within i might have a peek in the scrap bins a Goffs.

But the material to use i guess will have to be softer than the disks so maybe a softish copper alloy.

At the end of the day its only for a rear brake for bucket so i guess basically anything could work for a while anyway.........

[Grumph]

[QUOTE=husaberg;1130445667]From memory (out of George Beggs book)the rod were Cat Grader axles hammered flat with a power hammer after been reheated in a forge
Initially he used Ford Truck axels but they were not up to the job.
The pistons were initially a mix of ford and chev pistons (as in the movie) but the gudgeon's were always ford
The later Pistons were die cast from diesel pistons as he assumed they would have to be better quality than the petrol ones due to the higher pressures.
He however always used genuine Indian roller due to the radius edges which he reckon were les likely to shed there hadending.
these were heavily worked as it was very late in the piece that he actually converted to a pressure fed big end.He said it was to hard (which is funny considering the other modifications he made which were far more involved)
The majority of the time the crankpin he used was only 20mm which to me is is amazing.


The piston idea may be worth a crack....
but i suspect there with be a bit of steel reinforcing within i might have a peek in the scrap bins a Goffs.

I've come late to this but I've used alloy discs, anodised and non anodised. They only last if your rider doesn't use the back brake....

Just make up a disc in mild steel - the weight penalty is grammes only and it will see out a couple of seasons.
For rears, use as soft a pad as you can find.
Remember, during the 1960's Ferrari used mild steel discs.....
Till they learned about nodular cast iron anyway.

[husaberg]

From memory (out of George Beggs book)the rod were Cat Grader axles hammered flat with a power hammer after been reheated in a forge
Initially he used Ford Truck axels but they were not up to the job.
The pistons were initially a mix of ford and chev pistons (as in the movie) but the gudgeon's were always ford
The later Pistons were die cast from diesel pistons as he assumed they would have to be better quality than the petrol ones due to the higher pressures.
He however always used genuine Indian roller due to the radius edges which he reckon were les likely to shed there hadending.
these were heavily worked as it was very late in the piece that he actually converted to a pressure fed big end.He said it was to hard (which is funny considering the other modifications he made which were far more involved)
The majority of the time the crankpin he used was only 20mm which to me is is amazing.


The piston idea may be worth a crack....
but i suspect there with be a bit of steel reinforcing within i might have a peek in the scrap bins a Goffs.

I've come late to this but I've used alloy discs, anodised and non anodised. They only last if your rider doesn't use the back brake....


Just make up a disc in mild steel - the weight penalty is grammes only and it will see out a couple of seasons.
For rears, use as soft a pad as you can find.
Remember, during the 1960's Ferrari used mild steel discs.....
Till they learned about nodular cast iron anyway.

I know your right but where the fun in that Greg
I have a couple of disks here to play with but the wheel i are using is the STD front Honda pattern with a 57mm center and a 74mm pcd(on the Rear)
It need as great amount of offsett as the hub is narrow so trying to kill two birds with one stone.
I initally planed to modify a chinese rotor of a pitbike or similar but finding a suitable one has not been easy

[Ocean1]

From memory (out of George Beggs book)the rod were Cat Grader axles hammered flat with a power hammer after been reheated in a forge

Sounds right. Although I know he was given a Cat dozer (D7?) halfshaft to make rods from which was big enough to have taken a rod sized slice from.


it was very late in the piece that he actually converted to a pressure fed big end.He said it was to hard (which is funny considering the other modifications he made which were far more involved)
The majority of the time the crankpin he used was only 20mm which to me is is amazing.

Well, a dipper on the big end is a fairly reliable bit of kit for those revs, if the oil stays put in the sump. And I guess the small crankpin also means much lower surface speed eh?


The piston idea may be worth a crack....
but i suspect there with be a bit of steel reinforcing within i might have a peek in the scrap bins a Goffs.

But the material to use i guess will have to be softer than the disks so maybe a softish copper alloy.

At the end of the day its only for a rear brake for bucket so i guess basically anything could work for a while anyway.........

Bucket rear? Can you find a pushbike caliper to reach around the rim?

As for pads... one material used in't oldentimes was cork. Was compressed and encapsulated with (silica?) resin. Very high coeficient of grippything, wouldn't need much calliper force.

[husaberg]

Bucket rear? Can you find a pushbike caliper to reach around the rim?

As for pads... one material used in't oldentimes was cork. Was compressed and encapsulated with (silica?) resin. Very high coeficient of grippything, wouldn't need much calliper force.

The caliper is sorted and is a tiny one of a KTM 50 its is still attached to the bike otherwise a gentle breeze may blow it away.
Today I saw an interesting caliper set up from a Rokon i will ad it here as its quite quirky as the disk is solid yet the caliper with float effortlessly.

[Grumph]

i'd have thought you'd recognise a copy of early Honda.....

If you need a big offset on the disc, do an alloy carrier and float a mild steel disc on shouldered capscrews.

[husaberg]

i'd have thought you'd recognise a copy of early Honda.....

If you need a big offset on the disc, do an alloy carrier and float a mild steel disc on shouldered capscrews.

You would think so but no...
i looked at the pic and of a CR750 and still no
http://0.tqn.com/d/classicmotorcycles/1/0/c/-/-/-/Brakes-7-Honda-floating-caliper.jpg
Then kept google and by jove your tight Greg.....
http://honda-cb750-s.456789.n3.nabble.com/file/n4023373/caliper.jpg
it fairness they do predate me by more than a few years... Actually i have never seen a K0 or K1 or K2.
The old mans got a 350 four so i hope that's not the same set up as it does have a large bracket like that......

Yeah re the adapter spacer i have a criminal dislike verging on hatred of bolting on one piece only to bolt on another piece to it.
It doubles up the fastners ( as well as my chances of over tightening or loosing or leaving out etc)and the time to change the wheels, and the beer i will need to provide to the guy that will have to make it plus its all unsprung. I know it is OTT...

[speights_bud]

Yeah re the adapter spacer i have a criminal dislike verging on hatred of bolting on one piece only to bolt on another piece to it.
It doubles up the fastners ( as well as my chances of over tightening or loosing or leaving out etc)and the time to change the wheels, and the beer i will need to provide to the guy that will have to make it plus its all unsprung. I know it is OTT...


But how are guys who can supposed to get beer in their fridges?


C'mon get a pushie brake!, much lighter on un sprung weight, a little imagination can get you a quite cool adapter spacer too. (mines a bit average)

274338

[husaberg]

http://www.pentonpartsusa.com/images/2-%20wheels%20photos/461-13-080-000%20b%20rear%20brake.JPGhttp://i.ebayimg.com/00/s/MTIwMFgxNjAw/$T2eC16RHJHIE9nyseIKbBQYMmnjeVw~~60_35.JPGhttp://imgc.classistatic.com/cps/blnc/121127/135r1/6287lm9_20.jpeg
Same way i do beg the mrs for it......
The ktm 50 is made by Formula who also do MTB brakes they are tiny actually as small as my thumb designed to work with a 140mm disk.

[husaberg]

OK bit the bullet and coughed up $10 on one of these.
I was hopining the would be enough meat in the spokes to allow a direct bolt straight adapter on, but its only 8mm wide at the correct PCD

http://images.trademe.co.nz/photoserver/tq/46/203208746.jpg

its going on my CBR400 NC23 front wheel (rear wheel on my bucket)
the adaptor at this stake will possibly resemble this as i are no artist with a mill.
<img src="http://image.made-in-china.com/2f0j00TBQaEwIJsvgp/Integral-Pipe-Flange-Seagull.jpg" height="240px"/>


I already have a collection of RS125 sprockets. So i have to fab a mount for this as well most people think that i can get by without a cush drive but will be alright. (6mm bolts i think) 58mm center 78mm pcd 6 hole.

if i went cush i was thinking along the lines of a old Honda single set up with the tab dowels bolted on the sprocket.
The sprocket is then retained with the circlip to the hub so it would be QD with the rubbers in the adapter plate.

Along the lines of below to save space i guess i can go to Nolathane for the bushes.. rather than metalastic
<img src="http://www.davidsilverspares.co.uk/graphics/parts/41241222000P_large.jpg" height="240px"/><img src="http://i139.photobucket.com/albums/q320/bmcdonau/SL100/Picture1283.jpg" height="240px"/>

The adapter would end up looking like this only with the sprocket rather than the bearing retained by a circlip
<img src="http://www.brocksperformance.com/brocknm/articlefiles/BST_Gen_Maint_Cush_Drive_Wear_Zoom.jpg" height="240px"/>

Input from the panel??????????????????

[Ocean1]

Circlips go inside the bushes? How do you fit them?

Could use pins with a head inside the bush and a thread to retain the sprocket?

[husaberg]

Circlips go inside the bushes? How do you fit them?

Could use pins with a head inside the bush and a thread to retain the sprocket?

I will try and find a better pic the circlip only retains the sprocket which sandwiches the whole assembly.
the little xl and xr Honda's ran the system 70-80's
the pins bolt to the sprocket on on side pin on the other and the bushes are retained in the adaptor or in the little Hondas case the hub

<img src="http://images.powersportsnetwork.com/fiche/images/Honda/1973/Motorcycles/F14110012.gif" height="540px"/><img src="http://www.davidsilverspares.co.uk/graphics/parts/41241222000P_large.jpg" height="240px"/><img src="http://i139.photobucket.com/albums/q320/bmcdonau/SL100/Picture1283.jpg" height="240px"/>

[Grumph]

Firstly the disc carrier - fercrissake make it with some decent blending radii - avoid sharp section changes like your example pictured.

Sprocket carrier - the Honda style drive pins on the sprocket are a royal pain when it comes to changing gearing if you only have one set.Removing from one sprocket and putting into the next usually requires a vice to hold them....not fun at the track.

I'd put studs into the carrier and retain the RS sprockets with nylocs myself.

Everybody is right - for this application you don't need a cush. If you did or if you're being stubborn (bloody coaster)...what I've done previously is holesaw abt 35mm holes in the sprocket and use urethane bushes with large top hat alloy retainers held on with a countersunk capscrew. If you're short of space outboard of the sprocket this only comes out about 3mm from the sprocket face.
If you're not short of room, again,studs and nylocs.

[schrodingers cat]

Right not everyone knows this but all the late era MV Augustas (the Real MV's that finished in the 1970's) actually had aluminium alloy disk brake rotors.
I know many have experimented with plated and plasma coated aluminium alloy disk rotors without success.

MV supposedly had no trouble with the plain aluminum alloy rotors but what alloy might they have used and what sort of pad material would be suitable.

yes i realise an MMC material would be probably better but does anyone have any ideas?
I are picking that it would have to had a high silicon content....

Sprint car guys use alloys discs on occasions. How about starting your research there?
Mind you, why do you want an alloy disc?

[Grumph]

Right not everyone knows this but all the late era MV Augustas (the Real MV's that finished in the 1970's) actually had aluminium alloy disk brake rotors.
I know many have experimented with plated and plasma coated aluminium alloy disk rotors without success.

MV supposedly had no trouble with the plain aluminum alloy rotors but what alloy might they have used and what sort of pad material would be suitable.

yes i realise an MMC material would be probably better but does anyone have any ideas?
I are picking that it would have to had a high silicon content....

Just to finally clear this up - and stop Hus wasting time searching the net.....they were Harry Hunt plasma sprayed discs usually on Morris mags - bought as a package deal from California.
Harry kept his methodology close to his chest...it was believed there was a high bronze content in whatever he sprayed onto the alloy and he never said what alloy he used either AFAIK.
I think Harry may be dead now....

[husaberg]

Just to finally clear this up - and stop Hus wasting time searching the net.....they were Harry Hunt plasma sprayed discs usually on Morris mags - bought as a package deal from California.
Harry kept his methodology close to his chest...it was believed there was a high bronze content in whatever he sprayed onto the alloy and he never said what alloy he used either AFAIK.
I think Harry may be dead now....

Remember guys, i now have a mild steel Chinese disk made from recycled Woks............
the Works BSA and triumphs used aluminium disks that were sprayed (with some sort of steel:laugh:)
from 1970 on but cast iron rotors were used for the long races to aleviate overheating (classic racer winter 88)

Firstly the disc carrier - fercrissake make it with some decent blending radii - avoid sharp section changes like your example pictured.

Sprocket carrier - the Honda style drive pins on the sprocket are a royal pain when it comes to changing gearing if you only have one set.Removing from one sprocket and putting into the next usually requires a vice to hold them....not fun at the track.

I'd put studs into the carrier and retain the RS sprockets with nylocs myself.

Everybody is right - for this application you don't need a cush. If you did or if you're being stubborn (bloody coaster)...what I've done previously is holesaw abt 35mm holes in the sprocket and use urethane bushes with large top hat alloy retainers held on with a countersunk capscrew. If you're short of space outboard of the sprocket this only comes out about 3mm from the sprocket face.
If you're not short of room, again,studs and nylocs.
Yes us coaster are stubborn
it will have a nice radius like the fillet on a crank.I was too lazy to draw a pic...........
I are undecided the cush and more undecided about the pins. Some yams have the built in stud as part of the cush drive bush.
i have not measured the pins i have but i are guessing the RS sprocket holes are 2mm larger anyway.
with the STD Honda pin i put a spanner on them to remove them (They have a flat) but now there is no wreckers. i shudder to think what Honda would want for them new if i was to purchase 4-5 sets.

[Ocean1]

with the STD Honda pin i put a spanner on them to remove them (They have a flat) but now there is no wreckers. i shudder to think what Honda would want for them new if i was to purchase 4-5 sets.

I'm with everybody, the massive torque hammerstroke from an F4 combustion stroke doesn't warrent a cush.

If it did, I'd weld home made pins to every sprocket, the only thing you need to change one then is circlip pliers.

[ducatilover]

I got one!

Are two 6-8mm ish plates of alloy going to be strong enough for the front engine mount on my GN/DR600 thing... :shutup:

And Bogan, I should have them covers done by tomorrow after milking :D takes a bit long with the indented stuffs because I haven't got the dremel up here

[bogan]

Got the aformentioned spline shaper going today, see me other thread (http://www.kiwibiker.co.nz/forums/showthread.php/149096-What-bogan-is-bashing-together?p=1130453175#post1130453175) for details.


And Bogan, I should have them covers done by tomorrow after milking :D takes a bit long with the indented stuffs because I haven't got the dremel up here

Chur, rather you than me with that shit! And me frame/swinger and a few pairs of rearsets are waiting for a good polish whenever you get tired of pulling tits...

[Ocean1]

I got one!

Are two 6-8mm ish plates of alloy going to be strong enough for the front engine mount on my GN/DR600 thing... :shutup:

Plenty. In fact I'd be looking for areas to make big holes. If there's spacer tubes involved I'd use some heavy washers against the alloy or the compression will distort the surface and they'll work loose.

[husaberg]

I got one!

Are two 6-8mm ish plates of alloy going to be strong enough for the front engine mount on my GN/DR600 thing... :shutup:

And Bogan, I should have them covers done by tomorrow after milking :D takes a bit long with the indented stuffs because I haven't got the dremel up here


Plenty. In fact I'd be looking for areas to make big holes. If there's spacer tubes involved I'd use some heavy washers against the alloy or the compression will distort the surface and they'll work loose.

I am no engineer (that's for sure)
but one thing you must do is make sure the tread on the engine bolts are the correct length so the shank only bears against the alloy plates. Other wise it will wear the holes in the alloy plate bigger in no time, then it will vibrate, and then wear the holes bigger, etc, etc.

That's a tip from old pommy specials like Tritons.

[Brian d marge]

Sorry due to time I'm only able to the quick flippant reply
I flick through this thread , one minute brakes , now we are on to engine mounts , for a 150 four stroke ?
How much vibration and how much polish do we want
And what engine frame combo?

Steel and reamed holes is a good practice but as u may have read of people putting big singles in a alloy frame , the load , vibration paths weren't considered and it vibrates too much
Give me some calculations ,,,,,,:-) :-) :-) :-) ,,,
Stephen

[ducatilover]

Got the aformentioned spline shaper going today, see me other thread (http://www.kiwibiker.co.nz/forums/showthread.php/149096-What-bogan-is-bashing-together?p=1130453175#post1130453175) for details.



Chur, rather you than me with that shit! And me frame/swinger and a few pairs of rearsets are waiting for a good polish whenever you get tired of pulling tits... Choice, I'll pick 'em up one of these days :D


Plenty. In fact I'd be looking for areas to make big holes. If there's spacer tubes involved I'd use some heavy washers against the alloy or the compression will distort the surface and they'll work loose.


I am no engineer (that's for sure)
but one thing you must do is make sure the tread on the engine bolts are the correct length so the shank only bears against the alloy plates. Other wise it will wear the holes in the alloy plate bigger in no time, then it will vibrate, and then wear the holes bigger, etc, etc.

That's a tip from old pommy specials like Tritons. Cheers chaps!


Sorry due to time I'm only able to the quick flippant reply
I flick through this thread , one minute brakes , now we are on to engine mounts , for a 150 four stroke ?
How much vibration and how much polish do we want
And what engine frame combo?

Steel and reamed holes is a good practice but as u may have read of people putting big singles in a alloy frame , the load , vibration paths weren't considered and it vibrates too much
Give me some calculations ,,,,,,:-) :-) :-) :-) ,,,
Stephen
150cc?
Mine's a 589cc (currently...) in a shit steel frame :niceone: I want lots of polish, that's all I know... mine's a DR600 in to a GN250

[pete376403]

To save a bit of weight my bro-in-law made an aluminium rear disk for Bruce Ansteys TZ years back. It was only ever used in scruitineering.
when Bruce was on the brakes in a race the back wheel was usually off the ground anyway.

Oh and Kawasaki used plasma sprayed ally disks on the H2Rs back in the day

[husaberg]

Decent foundry to cast ally cylinders in CHCH is...............
From a very well made professional spec mold.
Add in costs if you know them 2kg.one of 1-20 there of........
I seriously want to do it out of old pistons Bert style but it's not a deal breaker:scratch:

[koba]

I got one!

Are two 6-8mm ish plates of alloy going to be strong enough for the front engine mount on my GN/DR600 thing... :shutup:

And Bogan, I should have them covers done by tomorrow after milking :D takes a bit long with the indented stuffs because I haven't got the dremel up here

Again, I'm no engineer but a big single in a small frame is going to be interesting.
Have you got a build thread?

[pete376403]

Take a look at a speedway bike as an example of "big engine minimalist frame" :rolleyes: Engine plates on those are 6mm aluminium

[Grumph]

Take a look at a speedway bike as an example of "big engine minimalist frame" :rolleyes: Engine plates on those are 6mm aluminium

Yeah, and the engine sprocket has to float to allow for frame flex......

[pete-blen]

Take a look at a speedway bike as an example of "big engine minimalist frame" :rolleyes: Engine plates on those are 6mm aluminium


Yeah, and the engine sprocket has to float to allow for frame flex......

The foating engine sprocket is a carry over from the old clutch system.. the clutch basket use to float when the clutch was pulled..
The new clutches the basket is fixed to the shaft...
Speedway frames do crack... but it takes a while... but then they are only running in anger for around 90 secs at a time..
think we use to cut out a lap of Nelson in 20/21secs on a good surface X 4..
When you come off the slide & the rear hooks up.. You can feel the frame trying to tie it self in knots.. one of the main
reasons they wobble in a straight line...

Had a Briggo Jawa / MK3 Weslake way back when..

[pete376403]

Lemesee - started with Mattingly framed JAP 4 stud, that engine (or bits of it) went into a NZ made replica Jawa frame, then the JAP got replaced by a Jawa 2v, then a Mk1 Weslake (horrible piece of unreliable shit), that got tossed for a Jawa 4V and thats more or less how it went for the 16 odd years that I was riding at te marua, with side trips to Wanganui, palmerston north, meanee and kihikihi. Bit of a 'grandfathers axe" bike. Love to try it again.

Sorry about hijacking the thread. As you were.

[Brian d marge]

Yeah, and the engine sprocket has to float to allow for frame flex......

Just been watching the Dakar , got a shot of the mini , very nice roll cage ,,,( not sure yet ) but looked monoque and very stiff

beautiful

Stephen
sod me , did I spell monoque correctly , damn ......

[Brian d marge]

The foating engine sprocket is a carry over from the old clutch system.. the clutch basket use to float when the clutch was pulled..
The new clutches the basket is fixed to the shaft...
Speedway frames do crack... but it takes a while... but then they are only running in anger for around 90 secs at a time..
think we use to cut out a lap of Nelson in 20/21secs on a good surface X 4..
When you come off the slide & the rear hooks up.. You can feel the frame trying to tie it self in knots.. one of the main
reasons they wobble in a straight line...

Had a Briggo Jawa / MK3 Weslake way back when..

hells bells

they were using an Enfield clutch , and a poorly designed frame ,

Damn

Stephen

ps the Enfield clutch is actually a clever design !

[ducatilover]

Right you clever buggers
Question/scenario thing

I have a plan, change my firing order to a "medium bang" set up.
Current is a typical flat plane crank (ZZR600D), waste spark and carbs
What I'm planning: 1&4 fire together, then 2/3 as normal.
So it'd be 1/4-2-nothing-3, repeat.

Reason, coz I want to.

The best idea I have seen so far has been the #4 lobes off, machine down the cam shaft then put it back together with the new timing by press fitting the two parts in a sleeve. (like an RC30 cam)

Now...
How tight am I wanting the sleeve,
Slightly smaller I/D than the O/D of the cam? Then heat it...lots...and press 'em together (in a jig to get timing right)

I also considered vaing a small keyway in the cam and sleeve to allign it, but I'm concerned it may weaken the sleeve.

Help an idiot out, for a choccy fush. :niceone:

I've been chatting to Bogan about it, but he hates 4cyls, so he's probably wanting me to do it and explode my motor so I have to buy another Bros650...

I'm also aware that the added effort to turn 1/4 over on the cimp stroke may be detrimental to the starter...or it may simply not have enough juice to turn over.

[bogan]

I've been chatting to Bogan about it, but he hates 4cyls, so he's probably wanting me to do it and explode my motor so I have to buy another Bros650...

Quite the opposite, gotta keep your grubby mitts of all the bros' by keeping you busy with the beige stuff :bleh:

I think, trying the heat method is worth a go, but also worth having a nice press available if it sticks and cools. Cos the smaller the shaft the less clearance you get for a given temperature rise (and the quicker the thermal transfer).

It'll be easy enough to machine up some holders for the lobe profiles with the required angular offset so they can just be slid along a bit of RHS as it is assembled, might even be just as easy to setup as a keyway anyway; and gives a better finished unit.

Also, don't worry about the starter, it'll be a case of what goes up must come down, harder to compress but then it'll put back a lot of that force on the downstroke... failing that, just call Ed!

[ducatilover]

:niceone: Righto- may employ you sometime this year to make the jiggy-thing. I have access to a few places in Palmy with heat/press, so we should be sorted.

I'm pretty sure I had some spare cams floating around at home, but may use the opportunity to get the late model ones I need:headbang:

[Ocean1]

What's the cam made out of?

And giz a pic, eh?

[ducatilover]

Not sure, probably cast iron, and I like the sleeved idea more than welding (that scares me)

I'll attemp to get a pic from teh googles, or try find the set of cams I have at home
http://i248.photobucket.com/albums/gg167/singram08/136-3652_IMG.jpg http://i254.photobucket.com/albums/hh116/alexbystrov/Bike parts/DSCN2601.jpg Being external oil feed I could even run a sleeve inside?

[Ocean1]

Not sure, probably cast iron, and I like the sleeved idea more than welding (that scares me)


Probably SG iron. Easy check: http://igor.chudov.com/manuals/Spark_Testing_for_Mystery_Metals.pdf

Can be welded fairly reliably but sleeving it carefully means you don't have to remachine journals. Measure up the clearance around the non-machined part of the shaft, reckon you want about 6mm wall thickness for a sleeve. If you've got the gear you can key the shaft/sleeve, but it'd want to be nice and shallow. You could also taper pin the sleeve through the shaft, and peen the small end. The sleeve wants to be 4140 or similar, probably 0.025 inteferance. Test warm sleeve before assembly to make sure you can get it up to size/size or you won't get it on.


Being external oil feed I could even run a sleeve inside?

Much lower torsional strength, though. I'd stick with external sleeves even if you have to machine the shaft down a couple of mm to make room for them.

Do you need to worry about assembling the completed item?

[husaberg]

Probably SG iron. Easy check: http://igor.chudov.com/manuals/Spark_Testing_for_Mystery_Metals.pdf

Can be welded fairly reliably but sleeving it carefully means you don't have to remachine journals. Measure up the clearance around the non-machined part of the shaft, reckon you want about 6mm wall thickness for a sleeve. If you've got the gear you can key the shaft/sleeve, but it'd want to be nice and shallow. You could also taper pin the sleeve through the shaft, and peen the small end. The sleeve wants to be 4140 or similar, probably 0.025 inteferance. Test warm sleeve before assembly to make sure you can get it up to size/size or you won't get it on.



Much lower torsional strength, though. I'd stick with external sleeves even if you have to machine the shaft down a couple of mm to make room for them.

Do you need to worry about assembling the completed item?

What he is wanting to do is fairly common with the triumphs and Nortons and BSA's (ie screwing with the firing order)for the 90 degree cranks there is few web sites....
i had an idea they were moded with a spline (but probably miles of) I'm not no engineer

[ducatilover]

Probably SG iron. Easy check: http://igor.chudov.com/manuals/Spark_Testing_for_Mystery_Metals.pdf

Can be welded fairly reliably but sleeving it carefully means you don't have to remachine journals. Measure up the clearance around the non-machined part of the shaft, reckon you want about 6mm wall thickness for a sleeve. If you've got the gear you can key the shaft/sleeve, but it'd want to be nice and shallow. You could also taper pin the sleeve through the shaft, and peen the small end. The sleeve wants to be 4140 or similar, probably 0.025 inteferance. Test warm sleeve before assembly to make sure you can get it up to size/size or you won't get it on.



Much lower torsional strength, though. I'd stick with external sleeves even if you have to machine the shaft down a couple of mm to make room for them.

Do you need to worry about assembling the completed item?

Thanks heaps mate! I'll try the spark test with a set of cams, then I'll measure it up and go from there
I'm now worried about the clearance between the shaft and the oil feed system with a sleeve on it, but I'll tackle that when I can get to the bike (next week)

No need to worry about assembling it. I can see external will be stronger anyway.

Should be an interesting project... Better for my life span than boosting it

[ducatilover]

What he is wanting to do is fairly common with the triumphs and Nortons and BSA's (ie screwing with the diring order)for the 90 degree cranks there is few web sites....
i had an idea they were moded with a spline (but probably miles of) I'm not no engineer

Cool, I'll have a looky and see what I can find about them!

As long as whatever I do is safe with revs (ZX6 pulls 15k, I can drop the limiter to 10k, but that's gay)

[Ocean1]

Thanks heaps mate! I'll try the spark test with a set of cams, then I'll measure it up and go from there

Actually those graphice are shite, see if you can google up some better spark pictures. Videos even...

[ducatilover]

No doubt there will be a few youtoooobe vids out there.
I would expect them to be cast iron though?

[carburator]

Mr ocean, ( clever bugger ) has discribed pretty close how to do it,
however Id do it his way with a couple of changes. and I have done this
for a cam train. external ajdustable sleves...

machine the cam for a sleve, make up a ajustable coupler ( think adjustable timing gear set )
or even machine coupler, scotch key it to the camshaft ( with a 0.015 shrink fit ) have a o ring grove
to contain the oil ( oil issue sloved ) but also it builds in adjustment to align both cams exact

Id do drawings on a napkin and photoshop it if you like but im on crayons at the moment..
and i can;t find the photo's of the one i did for a engine at the moment either..

but i used 4mm allen keys *6 and never had issues of movement plus I could dial the cam spot on..
no oil loss issue nor issues of alignment for journals..

[Ocean1]

No doubt there will be a few youtoooobe vids out there.
I would expect them to be cast iron though?

Chilled cast iron usually, and now you've got me thinking whether they use speroidal graphite or not...

Don't matter for the purpose of this excercise, and the sparks will look very similar. Actually if you can see rough cast surface there's almost no way it's steel, it'll be some sort of CI.

[Ocean1]

( with a 0.015 shrink fit )

Yes, perhaps a thou is a tad ambitious. Don't want too much heat on the sleeve, either.

[ducatilover]

Thanks Carb. The clearance issues I'm worried about are the sleeve hitting the oil feed rails that run over the cam as seen here http://i82.photobucket.com/albums/j256/zx6e/DSCN3624s.jpg I think I may just get away with it though... right, got to google the fancy engineering phrases (I'm only a mechanic!)

Could you elaborate on the adjustable coupler please? In my fuzzy brain I'm seeing to splined cups pressed on to each side of the cut in the cam...


Ocean, they're a cast surface, but I'll double-triple check at home.

[ducatilover]

There's also the cam locating ring on the exh side between 3 & 4, you'll see in the first pics.
I suppose this could be made to be incorporated in a sleeve?


Edit, after some googling, I think I'll go with a pressed in part, with a round keyway or two/scotch key. I'm confident it'll be up to the task!

[carburator]

Yes, perhaps a thou is a tad ambitious. Don't want too much heat on the sleeve, either.

Umm..

0.1 ( hundred thou )
0.01 ( ten thou )
0.001 ( one thou )

Oh bugger are you driving metric or imp ?

[carburator]

There's also the cam locating ring on the exh side between 3 & 4, you'll see in the first pics.
I suppose this could be made to be incorporated in a sleeve?


Edit, after some googling, I think I'll go with a pressed in part, with a round keyway or two/scotch key. I'm confident it'll be up to the task!

The cam locating thing you are refering to in the pictures ( thin disc ) is the splash oil system to get
oil to the inside of the camshaft. ( it does stop it moving around as well..)

Id be honest you get a bunch of engineers together and there always is different points of view..
Will draw ( find photos ) later on today..

[Ocean1]

Oh bugger are you driving metric or imp ?

Either. I design and build metric but I often convert to get a sort of "second opinion" for tolerances.

I'd originally suggested 0.025mm (1 thou), but 0.0125 (1/2 thou) is less likely to cause issues assembling it, and if the sleeve is reasonably long it'd be safe for whatever bending moments the shaft will get.

[ducatilover]

Either. I design and build metric but I often convert to get a sort of "second opinion" for tolerances.

I'd originally suggested 0.025mm (1 thou), but 0.0125 (1/2 thou) is less likely to cause issues assembling it, and if the sleeve is reasonably long it'd be safe for whatever bending moments the shaft will get.
The space I will have to use won't be very long, I'll measure it all up, but I expect I'll have somewhere between 50-60mm at the most for a sleeve

Just hunting eGay for a set of ZX6E cams now and we'll be in business
I'll have to figure out if the more aggressive profile will be beneficial, the E model has a more aggressive ramp on them compared to my D model but similar duration, so that'll increase the stress everywhere, and make it peakier.

I've answered my own question there, I'll use original cams...

[Ocean1]

The space I will have to use won't be very long, I'll measure it all up, but I expect I'll have somewhere between 50-60mm at the most for a sleeve

Should be OK, insertion depth the same as the diameter would mean bending forces are not agrivated through the sleeve.

Re scotch keys, how are you going to drill, (and ream?) the axial hole?

[bogan]

Re scotch keys, how are you going to drill, (and ream?) the axial hole?

And more importantly, are they even of any use in this application?

[ducatilover]

And more importantly, are they even of any use in this application?


Should be OK, insertion depth the same as the diameter would mean bending forces are not agrivated through the sleeve.

Re scotch keys, how are you going to drill, (and ream?) the axial hole?
No idea to both, that's why I've posted in here for you clever buggers :msn-wink:
I was assuming it'd help reduce the risk of the cam twisting in the join (remember, I know nussing about engineering stuff)

If it's not needed, I won't do it :niceone:

[pete376403]

Honda used, on the 6 cylinder CBX1000, Oldham couplers to join the two halves of the camshafts together. Would these suit your purpose?

[ducatilover]

That's quite the idea :niceone:

If the chaps here say it'll work, I will make that an option.
The cam lobe will be turned 180 deg, so it it doesn't run/sound pretty enough, I could in theory just turn it back around...

[bogan]

Do you have enough journals for that? Oldham couplers won't support the cam, so you need at least two journals on each side of it, if you're only doing the one cylinder you'll only have the end journal on the one side right?

[ducatilover]

Do you have enough journals for that? Oldham couplers won't support the cam, so you need at least two journals on each side of it, if you're only doing the one cylinder you'll only have the end journal on the one side right?
Ah, I see. Yup, journals are between the lobes, you can see where in the last pics.
I had my hopes up there, would work if I went for a big bang set up, but that'll root the rest of the engine... :rolleyes:

[ducatilover]

Here be a pic of where I'll be chopping/joining
276368

[Ocean1]

I was assuming it'd help reduce the risk of the cam twisting in the join (remember, I know nussing about engineering stuff)

If it's not needed, I won't do it :niceone:

It's quite possible a mild shrink fit on the sleeve would hold the torsional load, but I wouldn't trust it. Oldham couplers would be nice, if yo ucould buy them off the shelf, (fair bit of work to make) and if you had room to swing them. You dont. The simplest way to form a mechanical drive that'll fit in there is to pin a sleeve radially through the shafts both sides of the joint. I'd use taper pins, nominal dia about 5mm. Pre-assemble the shaft and check run-out and timing before reaming for pins.

All you need to do that is a lathe and a drill press, easy. I've got taper reamers if you decide to go that way. And pins.

[pete376403]

Bore through the centre of the camshaft, cut the shaft and put a spigot inside, give it a decent chamfer then bronze the thing back together in correct alignment

H-D did this with the rocker shafts on the original XR750 motors to get the angles right after shortening the 883 cylinders, so it's not like it's never been tried

[Ocean1]

Here be a pic of where I'll be chopping/joining
276368

What diameter is the shaft at the join? And what clearance does the standard shaft have from the oil runner?

[Ocean1]

Bore through the centre of the camshaft, cut the shaft and put a spigot inside, give it a decent chamfer then bronze the thing back together in correct alignment

H-D did this with the rocker shafts on the original XR750 motors to get the angles right after shortening the 883 cylinders, so it's not like it's never been tried

Yeah, it's an option. Think it'd work best if you made up a fairly substantial jig to keep it consentric.

[husaberg]

Cool, I'll have a looky and see what I can find about them!

As long as whatever I do is safe with revs (ZX6 pulls 15k, I can drop the limiter to 10k, but that's gay)
http://www.britcycle.com/Manuals/Building%20offset%20crankshafts%20for%20British%20 Twins.pdf
http://www.650motorcycles.com/270277updates.html
http://www.offsetcrank.com/thefirst.htm


Yeah, it's an option. Think it'd work best if you made up a fairly substantial jig to keep it consentric.
<img src="http://www.offsetcrank.com/images/cam_welding_fixture.jpg" width="340px"/>
http://www.offsetcrank.com/bike_cams.htm

[Brian d marge]

Im worried about the loading , while its not reversed it is repeated and again while the movement isn't big , the frequency is high and fatigue may be an issue, as well as the interference fit remember it will be running around 100 deg c more or let , which will affect any interference fits
the last idea with the bronze with a sleeve seems the most sturdy , but until you have an idea of the loading .....

Do a free-body diagram , then a loading diagram this will help you making a decision,

just my concerns

Stephen

[Ocean1]

massively oversizes pic

Perfekt...

[husaberg]

Perfekt...

Did you have a look at the links it did them in an interesting way.
the one i can't find it the Triumph that an Aussie did to try out Phil Irving 76 degree concept

[Kickaha]

Did you have a look at the links it did them in an interesting way.
the one i can't find it the Triumph that an Aussie did to try out Phil Irving 76 degree concept

There's a Matchless twin sidecar racing in NZ with a 76 degree crank the owner made himself

[DEATH_INC.]

What about stainless TIG? When I searched for info on welding gearshafts and stuff for the trike it was the most preferred method I found....

[Ocean1]

Did you have a look at the links it did them in an interesting way.
the one i can't find it the Triumph that an Aussie did to try out Phil Irving 76 degree concept

Briefly. They seemed to have more issues with cams than cranks.

[Ocean1]

What about stainless TIG? When I searched for info on welding gearshafts and stuff for the trike it was the most preferred method I found....

Is a good way to manage gear shafts, but they're carbon steel. Looks like this cam is cast iron, and while you can bronze weld cast iron with a TIG it's not the tool I'd use.

[husaberg]

Briefly. They seemed to have more issues with cams than cranks.

these bits one was the BSA and the other was the Megacycle fix for the yams both the same way i think

[Ocean1]

these bits one was the BSA and the other was the Megacycle fix for the yams both the same way i think

The BSA cam is steel, they've made a very heavy jig and TIG welded it.


The Megacycle cams in the pic look to be CI, they say "two lobes have been moved and hard welded in the new position".
The only "hard welding" I know about wouldn't be used to weld a shaft together, it'd be used to build up a lobe for re-grinding.

[ducatilover]

It's quite possible a mild shrink fit on the sleeve would hold the torsional load, but I wouldn't trust it. Oldham couplers would be nice, if yo ucould buy them off the shelf, (fair bit of work to make) and if you had room to swing them. You dont. The simplest way to form a mechanical drive that'll fit in there is to pin a sleeve radially through the shafts both sides of the joint. I'd use taper pins, nominal dia about 5mm. Pre-assemble the shaft and check run-out and timing before reaming for pins.

All you need to do that is a lathe and a drill press, easy. I've got taper reamers if you decide to go that way. And pins. Bummer, I expected the oldhams to be "relatively" straight forward.
Mr Bogan, do you reckon you can manage the idea Ocean1 has mentioned here? If so, I may have to send some cams your way


What diameter is the shaft at the join? And what clearance does the standard shaft have from the oil runner? Will get the measurements next week, still 450km away from the bike :facepalm:


Bore through the centre of the camshaft, cut the shaft and put a spigot inside, give it a decent chamfer then bronze the thing back together in correct alignment

H-D did this with the rocker shafts on the original XR750 motors to get the angles right after shortening the 883 cylinders, so it's not like it's never been tried
Don't quote me on this yet, but I think the ZX6/ZZR runs a hollow cam, but not for oil like Hondas of the era. This, to my noob head, seems like a good idea.


http://www.britcycle.com/Manuals/Building offset crankshafts for British Twins.pdf
http://www.650motorcycles.com/270277updates.html
http://www.offsetcrank.com/thefirst.htm



http://www.offsetcrank.com/bike_cams.htm I found those links last night after much trawling. I may be getting a little obsessed with this...


Im worried about the loading , while its not reversed it is repeated and again while the movement isn't big , the frequency is high and fatigue may be an issue, as well as the interference fit remember it will be running around 100 deg c more or let , which will affect any interference fits
the last idea with the bronze with a sleeve seems the most sturdy , but until you have an idea of the loading .....

Do a free-body diagram , then a loading diagram this will help you making a decision,

just my concerns

Stephen Cheers Stephen
I... errr... have no idea what these diagrams are, moar google for me!

Edit:
I really like the simplicity of Ocean1s idea, I think I'll have to get the measurements done, then look at it
The biggest issue I'm seeing here is I need to cut it where the locating ring is on the exh cam.
Will have to see how much clearance there is and if the sleeve can be made with the raised thingy in it
This shows the bit I'm waffling about http://img91.imageshack.us/img91/3116/dscf0891.jpg

The intake side has it on the gap between 1 & 2, so no issue there

[husaberg]

I found those links last night after much trawling. I may be getting a little obsessed with this...

Cheers Stephen
I... errr... have no idea what these diagrams are, moar google for me!

Hint....when you are searching it is often 4000% faster to use the image option?

[ducatilover]

Hint....when you are searching it is often 4000% faster to use the image option?
I do it a lot like that :niceone:
More pics to make my silly idea even closer to reality...
http://i29.photobucket.com/albums/c290/juffalo421/HPIM1764.jpg
I'll look up the spec for the cam journals so we have a vague reference as to the sizes of what's in there

[bogan]

Bummer, I expected the oldhams to be "relatively" straight forward.
Mr Bogan, do you reckon you can manage the idea Ocean1 has mentioned here? If so, I may have to send some cams your way

Yeh the hard bit will be the setup. Once I get em held in the lathe securely it'll be easy enough. Then again getting the setup right for pressing and pinning. You might have to buy me a boring bar though... and maybe some telescopic gauges too...

[ducatilover]

Yeh the hard bit will be the setup. Once I get em held in the lathe securely it'll be easy enough. Then again getting the setup right for pressing and pinning. You might have to buy me a boring bar though... and maybe some telescopic gauges too...
I don't like buying things :bleh:
Hopefully this link works
https://www.dropbox.com/s/g28bx6hollmo9pj/02.jpg has the journal specs

[Ocean1]

The biggest issue I'm seeing here is I need to cut it where the locating ring is on the exh cam.
Will have to see how much clearance there is and if the sleeve can be made with the raised thingy in it

The intake side has it on the gap between 1 & 2, so no issue there

Yeah, that might be a problem, the ring is about the diameter you'd want for a sleeve. If that makes it too hard to sleeve you migh need to look at an alternative, like either a dowel and braize joint or building up the lobes and getting them reground.

[ducatilover]

Yeah, that might be a problem, the ring is about the diameter you'd want for a sleeve. If that makes it too hard to sleeve you migh need to look at an alternative, like either a dowel and braize joint or building up the lobes and getting them reground.
I wanted to avoid re-ground lobes if possible (I'm a cheap bugger)
I suppose, because the cam seems to be hollow, I can't have it machined down quite a bit and press fitted

What's the likelihood of a braze joint warping the cam?

[Ocean1]

I wanted to avoid re-ground lobes if possible (I'm a cheap bugger)
I suppose, because the cam seems to be hollow, I can't have it machined down quite a bit and press fitted

What's the likelihood of a braze joint warping the cam?

Similar risk to welding, you'd still want to jig up for it.

You might want to think about hard soldering it, also. Joint prep might look like below.

As for cost, pretty much any way it could be done would be cheaper than having the joint fail.

[ducatilover]

What about modifying the locating groove? It's only on the oil feed and is a separate arm, there's no locating groove for the cam on the head. It could possibly be machine to accommodate a press fit sleeve with a locating ring machined on it?

Or cut the locating groove thingy off and have another made that is bolted to the oil feed gear

[Grumph]

Similar risk to welding, you'd still want to jig up for it.

You might want to think about hard soldering it, also. Joint prep might look like below.

As for cost, pretty much any way it could be done would be cheaper than having the joint fail.

Cut, bore both pieces using a travelling steady to hold the long piece. The cam is hollow simply to save weight - the insert doesn't need to be anything clever, mild steel will do, and it'll silver solder too. Pin it as well. The load, while interupted, isn't actually that great - i'd point out the huge number of cam sprockets which have been slotted and are held in place very effectively with two 6mm screws...

i disagree with the cost of failure...which ever cam breaks, the short end is going to stop with valves closed IMO...may be lucky and have no valve damage at all...If this actually works though, I'd not give a lot for the cush drive's chances in the back of the clutch.

[ducatilover]

So, if I run an internal one with pins/weld, would it be wise to put the pins through before brazing the joint?

Could it even be possible to run a pinned internal rod, without weld?

[Ocean1]

Cut, bore both pieces using a travelling steady to hold the long piece. The cam is hollow simply to save weight - the insert doesn't need to be anything clever, mild steel will do, and it'll silver solder too. Pin it as well. The load, while interupted, isn't actually that great - i'd point out the huge number of cam sprockets which have been slotted and are held in place very effectively with two 6mm screws...

i disagree with the cost of failure...which ever cam breaks, the short end is going to stop with valves closed IMO...may be lucky and have no valve damage at all...If this actually works though, I'd not give a lot for the cush drive's chances in the back of the clutch.

Right you are gov'nor, see pic. Edit: you'd want to machine the shaft OD first.


So, if I run an internal one with pins/weld, would it be wise to put the pins through before brazing the joint?

Could it even be possible to run a pinned internal rod, without weld?

With Easyflow or similar you'd make most of the length of the joint about 0.05mm clearance, with perhaps the centre 4mm of the pin size for size. Tin the pin and cam bores, lay it into a simple jig to keep it aligned and timed, heat it up to about 650c and push the lot firmly together. As long as the surfaces are tinned properly that won't move, but it takes a mere 10 minutes to cross drill and ream the assembly and fit taper pins.

Editedit: You could probably use the same technique with the appropriate loctite instead of solder.

[ducatilover]

With Easyflow or similar you'd make most of the length of the joint about 0.05mm clearance, with perhaps the centre 4mm of the pin size for size. Tin the pin and cam bores, lay it into a simple jig to keep it aligned and timed, heat it up to about 650c and push the lot firmly together. As long as the surfaces are tinned properly that won't move, but it takes a mere 10 minutes to cross drill and ream the assembly and fit taper pins.

Editedit: You could probably use the same technique with the appropriate loctite instead of solder.
:niceone: I think this is the nicest sounding idea so far.
If I can pull this off, I'll have to owe you a beverage too :first:
Nice and simple, I like simple

[bogan]

With Easyflow or similar you'd make most of the length of the joint about 0.05mm clearance, with perhaps the centre 4mm of the pin size for size. Tin the pin and cam bores, lay it into a simple jig to keep it aligned and timed, heat it up to about 650c and push the lot firmly together. As long as the surfaces are tinned properly that won't move, but it takes a mere 10 minutes to cross drill and ream the assembly and fit taper pins.

Editedit: You could probably use the same technique with the appropriate loctite instead of solder.

With loctite would you get away with a smaller clearance? I'm just thinking the jig would difficult to make, so if we could get away with just fitting it together and pinning it that would be awesome.

[pete376403]

Can cast iron be silver soldered? (easyflow/silfos are the only two I learned of, but that was a long time ago)

[Ocean1]

With loctite would you get away with a smaller clearance? I'm just thinking the jig would difficult to make, so if we could get away with just fitting it together and pinning it that would be awesome.

Yes. Less secure but probably OK, and you don't have issues with the heat distorting shit or damagine hardening. I'd look at the cam joint prep wall thickness as the weak point, make the pin a couple of mm smaller to compensate. And make sure the bottom of the bore is radiused. Think the shaft OD was 24mm nom? What size is the existing hole down the shaft?

Loctite 640 (iirc) is for high temp close tolerance applications. Needs to be oil resistant too, check if it's been superseeded. You'd have to research clearances but I suspect you'd get away with as little as 0.005mm. Guess you could dummy assemble it, set the timing up right and then drill and ream for taper pins before taking the lot apart to clean and glue. I'd cut the pins 1mm proud on the minor dia side and csk that side of the hole very slightly, so you can carefully peen the pin after it's well tapped home.

How critical is the journal to journal pitch, are you going to get away with losing the thickness of the cut, (1.5mm?) or do you need two doner cams?

[Ocean1]

Can cast iron be silver soldered? (easyflow/silfos are the only two I learned of, but that was a long time ago)

I've had trouble with shit grey iron, heaps of free graphite, but I think you'd be OK with anything they'd make a cam out of.

[ducatilover]

Yes. Less secure but probably OK, and you don't have issues with the heat distorting shit or damagine hardening. I'd look at the cam joint prep wall thickness as the weak point, make the pin a couple of mm smaller to compensate. And make sure the bottom of the bore is radiused. Think the shaft OD was 24mm nom? What size is the existing hole down the shaft?

Loctite 640 (iirc) is for high temp close tolerance applications. Needs to be oil resistant too, check if it's been superseeded. You'd have to research clearances but I suspect you'd get away with as little as 0.005mm. Guess you could dummy assemble it, set the timing up right and then drill and ream for taper pins before taking the lot apart to clean and glue. I'd cut the pins 1mm proud on the minor dia side and csk that side of the hole very slightly, so you can carefully peen the pin after it's well tapped home.

How critical is the journal to journal pitch, are you going to get away with losing the thickness of the cut, (1.5mm?) or do you need two doner cams?
The first two paragraphs are a wee bit above me...

I hadn't actually considered the cut. I think there's a tiny bit of room to play with, but I personally wouldn't try much
I suppose some sort of spacer may be needed? If I had, say, 2mm taken with the cut and run a 2mm spacer in it?

[Canis G.]

Is there a reason why stainless exaust studs are not used on bikes (I am thinking air-cooled here)? Seems it would make it a damn site easier to remove exausts etc instead of dealing with gunged up steel ones.

Cheers for your patience.

[bogan]

Is there a reason why stainless exaust studs are not used on bikes (I am thinking air-cooled here)? Seems it would make it a damn site easier to remove exausts etc instead of dealing with gunged up steel ones.

Cheers for your patience.

Stainless has more potential to corrode inside the aluminium head. They just went with the lesser of two evils and kept the corrosion on the outside. Though cost is probably a factor too.

[Ocean1]

It also cold-welds to itself, you have trouble with nuts siezing onto bolts with SS unless you use the right lubricants. It's also not as strong, (generally) as most modern fasteners materials. Having said that I've never been happy with the common OE practice of using cadnium plated screws in alloy cases, and I've used SS replacements before now.

Edit: good thread lubricant and general all-round corrosion preventitive is Prolan, (lanolin) available from most fasteners suppliers.

[carburator]

Stainless has more potential to corrode inside the aluminium head. They just went with the lesser of two evils and kept the corrosion on the outside. Though cost is probably a factor too.

thermal exspanion properties..
get liberal with copper or zinc or never seaise and no issues or either happening..
however i did use copper washers and brass nuts ( lockwired ) on a mainfold that
we would take on and off a lot ( racing )

[imdying]

How about Ti studs? If you had a bike with Ti exhaust studs, what sort of nuts would you use on them?

[carburator]

How about Ti studs? If you had a bike with Ti exhaust studs, what sort of nuts would you use on them?

Ti is a pain in the ass more so for heat cycles, Inconel studs if you really need the strenght factor, however over the
years ( lost count ) how many Ive drilled out on LPT cases is not funny and after a couple of heat cycles are hard MO Fo's
to drill out if snapped off..

end of the day MS ( mild steel ) zinc plated work well for non turbo applications.. or anything really..

[schrodingers cat]

end of the day MS ( mild steel ) zinc plated work well for non turbo applications.. or anything really..

Regular maintanence? It will never catch on

[Ocean1]

How about Ti studs? If you had a bike with Ti exhaust studs, what sort of nuts would you use on them?

Depends. Why are the studs Ti? Is the extra tensile strength needed? If not I'd get rid of them, it's almost impossible to predict service duty cycles for it, they might crack any time.

I'd look at AB2 nuts at a full dia length, (8mm long for an M8 thread) for Ti exhause studs. If they wern't up to the strength requirements then I'd probably get rid of the Ti studs anyway and uprate the thread size.

Edit: Sorry, AB2 is an aluminium bronze alloy.

[Ocean1]

Ti is a pain in the ass more so for heat cycles, Inconel studs if you really need the strenght factor, however over the
years ( lost count ) how many Ive drilled out on LPT cases is not funny and after a couple of heat cycles are hard MO Fo's
to drill out if snapped off..

end of the day MS ( mild steel ) zinc plated work well for non turbo applications.. or anything really..

Oversizing studs has an advantage beyond reducing the requirement for high-strung materials, you can pre-drill a 2-3mm hole up the full length. You've got surplus CSA anyway, and it makes drilling the wee fuckers out SO much easier of they fail.

PS, anyone seen LH drills for sale recently? I've managed to fuck most of my limited supply.

[pete-blen]

Right you clever buggers
Question/scenario thing

I have a plan, change my firing order to a "medium bang" set up.
Current is a typical flat plane crank (ZZR600D), waste spark and carbs
What I'm planning: 1&4 fire together, then 2/3 as normal.
So it'd be 1/4-2-nothing-3, repeat.

Reason, coz I want to.

The best idea I have seen so far has been the #4 lobes off, machine down the cam shaft then put it back together with the new timing by press fitting the two parts in a sleeve. (like an RC30 cam)

Now...
How tight am I wanting the sleeve,
Slightly smaller I/D than the O/D of the cam? Then heat it...lots...and press 'em together (in a jig to get timing right)

I also considered vaing a small keyway in the cam and sleeve to allign it, but I'm concerned it may weaken the sleeve.

Help an idiot out, for a choccy fush. :niceone:

I've been chatting to Bogan about it, but he hates 4cyls, so he's probably wanting me to do it and explode my motor so I have to buy another Bros650...

I'm also aware that the added effort to turn 1/4 over on the cimp stroke may be detrimental to the starter...or it may simply not have enough juice to turn over.



Been there done that... made a GSXR750 think it was a twin...
for one of my TQ midgets...
Cut the cams turn one end 180* re-weld back togeather..
change the plug leads..
just don't try to rev it it 11,000 rpm... set the red line about 7500/8000
and make use of the massive torque it will gain..

Gavin Sendle/Craig Webby won the NZ speedway side car champs with a
GSXR1100 running as a twin..

[ducatilover]

Been there done that... made a GSXR750 think it was a twin...
for one of my TQ midgets...
Cut the cams turn one end 180* re-weld back togeather..
change the plug leads..
just don't try to rev it it 11,000 rpm... set the red line about 7500/8000
and make use of the massive torque it will gain..

Gavin Sendle/Craig Webby won the NZ speedway side car champs with a
GSXR1100 running as a twin..

That's a proper big bang though, this is only a half arse one :2thumbsup


I have a set of ZZR400k cams in the garage, same journals as the 600 ones and same dimensions, except lobe height.
I could experiment with them?
They're not hollow, just have indents in each end for the magic cam making machine or some shit

[Flip]

Coppercoat is IMHO the best thread lubricant to stop exhaust threads binding up. In the old days they used to use brass nuts on exhausts.

[imdying]

The why is easy; they came with an engine. I have some long brass manifold nuts I thought I might try.

Drills Taps and Dies have LH twist drill bits.

[carburator]

The why is easy; they came with an engine. I have some long brass manifold nuts I thought I might try.

Drills Taps and Dies have LH twist drill bits.

Umm, in the years Ive been doing it, never seen taps come with a LH drills
as for Die's you don't need to drill a hole for them...

[Ixion]

Umm, in the years Ive been doing it, never seen taps come with a LH drills
as for Die's you don't need to drill a hole for them...


He means the company "Drills Taps and Dies Ltd" in Christchurch. These dudes (https://www.drillstapsdies.co.nz/products.html?cid=879).

And they do indeed list LH jobber drills. Available online no less! Location on the site is a bit obscure bt the link takes you straight there.

[imdying]

Umm, in the years Ive been doing it, never seen taps come with a LH drills
as for Die's you don't need to drill a hole for them...Never said they did!

[Ocean1]

The why is easy; they came with an engine. I have some long brass manifold nuts I thought I might try.

Wasn't trying to imply that Mr Honda (et al) don't know their shit, it's just that I've see Ti fail so many times in new applications. It seems to behave quite differently to "normal" materials, and the failure mode and frequency is very difficult to predict. Brass nuts should be fine as long as you've got enough extra length. If you want AB2 nuts let me know, I've got some round bar stock here.


Drills Taps and Dies have LH twist drill bits.

Cheers, looks like a fairly good selection too if they actually stock what they've got listed. When I'm feeling braver I'll ask them about prices.

[carburator]

Never said they did!

Ah, Id better go and shoot a crow, bast and slow roast it so I can eat humble crow..

did'nt realise you mean't a company..

[HenryDorsetCase]

Ah, Id better go and shoot a crow, bast and slow roast it so I can eat humble crow..

did'nt realise you mean't a company..

At last I can contribute! First slow cook it like you would lamb shanks*: so get the crow in a pot and put in onion, carrot, celery, bay leaf, beef stock and red wine, some herbs and whatnot, and cook it for a few hours till tender. reserve the liquid, and put the crow in the fridge overnight. When you want to serve it, roast it uncovered for 45mins or an hour till the skin is crispy. Meanwhile, get the fat off your cooking liquid and reduce it till syrupy. Serve with new potatoes and seasonal veges, sauce over the top and more on the side.



*This works a treat for duck so should work with most game birds.

[imdying]

Wasn't trying to imply that Mr Honda (et al) don't know their shit, it's just that I've see Ti fail so many times in new applications. It seems to behave quite differently to "normal" materials, and the failure mode and frequency is very difficult to predict. Brass nuts should be fine as long as you've got enough extra length. If you want AB2 nuts let me know, I've got some round bar stock here..They're not factory, they just came with a 'race' motor I purchased... I know the previous owner has had a couple of them with a bit of Ti hardware all over them, so presumably they're reasonable adequate. It's only for the track, so not the end of the world if one breaks :) Yup, nice long manifold nuts like you'd see on much older vehicles, I'll see how they go with some Coppaslip or similar. The way I figure it, even if they're not really suitable, they'll be soft enough to remove without too much hassle?

[Ocean1]

The way I figure it, even if they're not really suitable, they'll be soft enough to remove without too much hassle?

The nuts? Yes, worst case clean up the studs with a dienut.

[sootie]

Been there done that... made a GSXR750 think it was a twin...
for one of my TQ midgets...
Cut the cams turn one end 180* re-weld back togeather..
change the plug leads..
just don't try to rev it it 11,000 rpm... set the red line about 7500/8000
and make use of the massive torque it will gain..

I can understand limiting the revs with the engine firing more unbalanced, but do you really gain torque??
I would have thought the road grip on dirt or gravel might improve, but why does engine torque change (if this was what you meant) ? :confused:

[Grumph]

I can understand limiting the revs with the engine firing more unbalanced, but do you really gain torque??
I would have thought the road grip on dirt or gravel might improve, but why does engine torque change (if this was what you meant) ? :confused:

Total torque per engine firing cycle doesn't change but instead of getting it in four small lumps at pretty even intervals, it comes in two big lumps spaced further apart....technically, peak torque values seen at the clutch and gearbox are doubled....

Which is why I said earlier i wouldn't give much for the cush drive in the Kawa clutch's chances of survival...they don't have a good reputation as standard.

i'm curious about the GSXR though -I've built a lot of TQ GSXR's and wonder what the limiting factor was. I'd assume diff drive cos a std box would not take it. Mains cutting out with shaft flex ? That is a low rev limit....

[pete-blen]

Total torque per engine firing cycle doesn't change but instead of getting it in four small lumps at pretty even intervals, it comes in two big lumps spaced further apart....technically, peak torque values seen at the clutch and gearbox are doubled....

Which is why I said earlier i wouldn't give much for the cush drive in the Kawa clutch's chances of survival...they don't have a good reputation as standard.

i'm curious about the GSXR though -I've built a lot of TQ GSXR's and wonder what the limiting factor was. I'd assume diff drive cos a std box would not take it. Mains cutting out with shaft flex ? That is a low rev limit....

No it was a chain drive car... but as you will know the GSXR750 had a weak 2nd gear when used as the main drive gear...
We use to put GS1000 gears in... had to cut a new cerclip groove in the shaft... then remove the other GSXR gears so
you only had in gear / out of gear..

[carburator]

At last I can contribute! First slow cook it like you would lamb shanks*: so get the crow in a pot and put in onion, carrot, celery, bay leaf, beef stock and red wine, some herbs and whatnot, and cook it for a few hours till tender. reserve the liquid, and put the crow in the fridge overnight. When you want to serve it, roast it uncovered for 45mins or an hour till the skin is crispy. Meanwhile, get the fat off your cooking liquid and reduce it till syrupy. Serve with new potatoes and seasonal veges, sauce over the top and more on the side.



*This works a treat for duck so should work with most game birds.

have to find the photos of the ravens.. more meat than a crow..

[ducatilover]

Which is why I said earlier i wouldn't give much for the cush drive in the Kawa clutch's chances of survival...they don't have a good reputation as standard.



:laugh: It's a 22 year old shit heap, so it's going to explode anyway (incidentally, my 2nd gear is mint. Seems to be the only one ever to not run second, it never will with my nana riding...)

I'm hoping the one large pulse won't be too hurtful.
I could always experiment with the ZZR400K cams, but it'll take some huge mongrel shims to pull the clearances to spec...
Unless I have a set of 400 buckets still, but I'm pretty certain the 600 ran bigger springs.

[Canis G.]

It also cold-welds to itself, you have trouble with nuts siezing onto bolts with SS unless you use the right lubricants. It's also not as strong, (generally) as most modern fasteners materials. Having said that I've never been happy with the common OE practice of using cadnium plated screws in alloy cases, and I've used SS replacements before now.

Edit: good thread lubricant and general all-round corrosion preventitive is Prolan, (lanolin) available from most fasteners suppliers.

So given issues of strength (how much weaker than equivalent sized HT steel?) and corrosion (I assuming galvanic - what's in the alloy that reacts with ali? and what works as the electrolyte?) could you use stainless studs with plain steel nuts to prevent the seizing?

I hear what you are saying about Prolan - thanks for the tip.

Cheers

[pete-blen]

So given issues of strength (how much weaker than equivalent sized HT steel?) and corrosion (I assuming galvanic - what's in the alloy that reacts with ali? and what works as the electrolyte?) could you use stainless studs with plain steel nuts to prevent the seizing?

I hear what you are saying about Prolan - thanks for the tip.

Cheers

If you are putting stainless bolts in alloy use "lanocote" it stops seizeing & electrolysis
stainless & alloy are the two worst metals to put togeather..
Over tighting stainless bolts & nuts can cause the stainless to pick up & lock togeather..
DON"T use a stainless bolt in alloy for a earth strap ..

[Ocean1]

So given issues of strength (how much weaker than equivalent sized HT steel?) and corrosion (I assuming galvanic - what's in the alloy that reacts with ali? and what works as the electrolyte?) could you use stainless studs with plain steel nuts to prevent the seizing?

I hear what you are saying about Prolan - thanks for the tip.

Cheers

The corrosion is usually galvanic, not nescessarily electrolytic, it's enough that the metals are in contact and significantly seperated on the table.

Without looking it up I'd say stainless's tensile performance is typically a fair bit better than mild steel and maybe 80% of an 8.8 fastener. It varies quite a bit as it work hardens and the production process, (particularly rolled threads) often produces bolts a bit stronger than normal.

As for mixing nuts/stud material, stainless in close contact with ferrous oxide behaves exactly like ferrous materials. It rusts.

Prolan not only lubricates and excludes atmospheric oxygen and other chemicals, it actually prevents galvanic corrosion. No idea why. A friend is a very senior chemical engineer, he's got no idea either.

[koba]

No idea why. A friend is a very senior chemical engineer, he's got no idea either.

Cool. I like that.

[husaberg]

Cool. I like that.

He'd still charge you for the report though:laugh:

[Ocean1]

He'd still charge you for the report though:laugh:

Bit of a specialist, can tell you anything you want to know about materials. Once fitted a radio to his car, bit of a tight fit and it stuck out from the dash a bit but he was dead proud of it. I got a call next morning, he'd started the car to go to work and... couldn't get first gear.

[koba]

Bit of a specialist, can tell you anything you want to know about materials. Once fitted a radio to his car, bit of a tight fit and it stuck out from the dash a bit but he was dead proud of it. I got a call next morning, he'd started the car to go to work and... couldn't get first gear.

:facepalm: Hammer?

[speights_bud]

Year one of Apprentiship paperwork, don't fit steel to alloy where vibrations occur, something about galvanic corrosion as mentioned earlier... or something... its too late to think hard. example was aluminium tv aerial on a tin roof blowing in the wind.

[Ocean1]

Year one of Apprentiship paperwork, don't fit steel to alloy where vibrations occur, something about galvanic corrosion as mentioned earlier...

Generally try to avoid having materials from too far apart on this list in hard contact:

Active (Anodic)

Magnesium
Mg alloy AZ-31B
Mg alloy HK-31A
Zinc (hot-dip, die cast, or plated)
Beryllium (hot pressed)
Al 7072 clad on 7075
Al 2014-T3
Al 1160-H14
Al 7079-T6
Cadmium (plated)
Uranium
Al 218 (die cast)
Al 5052-0
Al 5052-H12
Al 5456-0, H353
Al 5052-H32
Al 1100-0
Al 3003-H25
Al 6061-T6
Al A360 (die cast)
Al 7075-T6
Al 6061-0
Indium
Al 2014-0
Al 2024-T4
Al 5052-H16
Tin (plated)
Stainless steel 430 (active)
Lead
Steel 1010
Iron (cast)
Stainless steel 410 (active)
Copper (plated, cast, or wrought)
Nickel (plated)
Chromium (Plated)
Tantalum
AM350 (active)
Stainless steel 310 (active)
Stainless steel 301 (active)
Stainless steel 304 (active)
Stainless steel 430 (active)
Stainless steel 410 (active)
Stainless steel 17-7PH (active)
Tungsten
Niobium (columbium) 1% Zr
Brass, Yellow, 268
Uranium 8% Mo.
Brass, Naval, 464
Yellow Brass
Muntz Metal 280
Brass (plated)
Nickel-silver (18% Ni)
Stainless steel 316L (active)
Bronze 220
Copper 110
Red Brass
Stainless steel 347 (active)
Molybdenum, Commercial pure
Copper-nickel 715
Admiralty brass
Stainless steel 202 (active)
Bronze, Phosphor 534 (B-1)
Monel 400
Stainless steel 201 (active)
Carpenter 20 (active)
Stainless steel 321 (active)
Stainless steel 316 (active)
Stainless steel 309 (active)
Stainless steel 17-7PH (passive)
Silicone Bronze 655
Stainless steel 304 (passive)
Stainless steel 301 (passive)
Stainless steel 321 (passive)
Stainless steel 201 (passive)
Stainless steel 286 (passive)
Stainless steel 316L (passive)
AM355 (active)
Stainless steel 202 (passive)
Carpenter 20 (passive)
AM355 (passive)
A286 (passive)
Titanium 5A1, 2.5 Sn
Titanium 13V, 11Cr, 3Al (annealed)
Titanium 6Al, 4V (solution treated and aged)
Titanium 6Al, 4V (anneal)
Titanium 8Mn
Titanium 13V, 11Cr 3Al (solution heat treated and aged)
Titanium 75A
AM350 (passive)
Silver
Gold
Graphite

End - Noble (Less Active, Cathodic)

Note that the terms "stainless" and "alluminium" are very broad descriptions.


The vibration thing may be more to do with what's called fretting corrosion, where the surfaces actually rub together, it produces fairly distinct corrosion patterns. It's not unheard of on headstock and swingarm bearing surfaces.

[Canis G.]

Thanks for your time and answers Ocean (and others) - much appreciated. Guess I will stick to steel studs and prolan.

[husaberg]

iron sleeves in Two strokes
Niksil is a much better option i realise this of course.:yes:

The early japanese engines have cast in iron sleves right.IE MB100's RD250's/400 plus many others

The sleeves appear to be corrugated i guess to aid surface area and to make sure they don't move.

With a pressed in interference fit iron sleeve and a aluminum cylinder the heat transfer is not so good.
A few people have mentioned carbon builds up behind them further impeding the heat transfer.

Has anyone ever done a thread in sleeves where a thread would be formed (on the sleeve and bore)and the sleeve held in this way?
putting aside the difficulty lining up the ports (i think this would be no worse certainly less fraught with a misalignment or jam)

Would the increased surface area aid transfer of heat is it achievable, would it be cost effective?

As an aside i see the new Yamaha 150 or 125 four stroke road bike has a non coated alloy cylinder with i believe a very high silicon content.

[Kickaha]

With a pressed in interference fit sleeve and a aluminum cylinder the heat transfer is not so good.
You mean with a cast sleeve? would an alloy sleeve and nicasil be any better? close to $1000 when I asked about it being done

[husaberg]

You mean with a cast sleeve? would an alloy sleeve and nicasil be any better? close to $1000 when I asked about it being done

yes I mean with a cast iron sleeve.
And yes i think a aluminum alloy sleeve coated would be preferable but bloody costly.

Sometimes a sleeve is unavoidable like when attempting to make a smaller bore engine.

I actually wondered about filling the entire cylinder with alloy weld and then machining and plating, but was laughed at for the suggestion (note that's how some cylinders are repaired)

[Grumph]

yes I mean with a cast iron sleeve.
And yes i think a aluminum alloy sleeve coated would be preferable but bloody costly.

Sometimes a sleeve is unavoidable like when attempting to make a smaller bore engine.

I actually wondered about filling the entire cylinder with alloy weld and then machining and plating, but was laughed at for the suggestion (note that's how some cylinders are repaired)

There's been a lot of things tried - read the old books.

The neatest one I know of was Herman Meier when he was developing the Royal Enfield 250. He did a chrome plated alloy sleeve which was of a different alloy to the cast barrel - get the right interference fit and temperature differential and it dropped out. Slip fit at room temp but stuck fast when hot....easy to change things.

Most continental and british sleeved cylinders are a plain parallel wall sleeve. Unfortunately most Jap cylinders since 1970 have been odd shaped liners cast in.....

[husaberg]

There's been a lot of things tried - read the old books.

The neatest one I know of was Herman Meier when he was developing the Royal Enfield 250. He did a chrome plated alloy sleeve which was of a different alloy to the cast barrel - get the right interference fit and temperature differential and it dropped out. Slip fit at room temp but stuck fast when hot....easy to change things.

Most continental and british sleeved cylinders are a plain parallel wall sleeve. Unfortunately most Jap cylinders since 1970 have been odd shaped liners cast in.....

I think that Wellworthy invented the cast in sleeve or at least patented one form of it which is very British...........
trying to avoid the cost of the plating but yes it way be unavoidable.

What would be the pros cons on a threaded cast iron sleeve in execution rather than vs Niksil.
Also some suggested reading material Greg.

[Ocean1]

I've thought about it. Never had sufficient cause to try it. The surface contact area thing's not clear cut, either, if you look closely at a good quality commercial bolt you'll see the thread form is rounded at the peaks, in a nut the minor dia peaks are flattened. Typically just 75% of the theoretical mating faces actually contact. With careful machining you could optimise the profile and get that up around 90%, but whereas it's reasonably easy to achieve good surface contact with a smooth cylindrical liner even with ground threads I doubt you'd get anywhere near that 90%. And you ain't going to grind the internal alloy thread anyway.

Long and short: good idea if you assume perfect threads, but very difficult to execute.

Not sure what would prompt a departure from chrome on alloy. You've got the best of both worlds, very hard surface chemically bonded to a lightweight structural material with a very high thermal coefficient. And relatively cheap.

Now that I think about it what implications would ceramic bore coatings have wrt heat? I guess if not much heat's transfering into a ceramic cylinder wall you don't have to get rid of it, eh? OTOH a colder cylinder could cause grief with combustion dynamics...

[husaberg]

I've thought about it. Never had sufficient cause to try it. The surface contact area thing's not clear cut, either, if you look closely at a good quality commercial bolt you'll see the thread form is rounded at the peaks, in a nut the minor dia peaks are flattened. Typically just 75% of the theoretical mating faces actually contact. With careful machining you could optimise the profile and get that up around 90%, but whereas it's reasonably easy to achieve good surface contact with a smooth cylindrical liner even with ground threads I doubt you'd get anywhere near that 90%. And you ain't going to grind the internal alloy thread anyway.

Long and short: good idea if you assume perfect threads, but very difficult to execute.

Not sure what would prompt a departure from chrome on alloy. You've got the best of both worlds, very hard surface chemically bonded to a lightweight structural material with a very high thermal coefficient. And relatively cheap.

Now that I think about it what implications would ceramic bore coatings have wrt heat? I guess if not much heat's transfering into a ceramic cylinder wall you don't have to get rid of it, eh? OTOH a colder cylinder could cause grief with combustion dynamics...

Niksil and the others are i believe semi ceramic click the arrow Chrome is old school and not so good for 2 smokes.

here

[Ocean1]

Niksil and the others are i believe semi ceramic click the arrow Chrome is old school and not so good for 2 smokes.

Apologies, I meant "whatever shiny stuff they're electroplating onto alloy bores nowadays", rather than actual simple chrome.

I'll read that wee article when I've got half an hout to figure out how to size it so I can see it and have it STAY that size. However, I'll bet you a pound to a pinch of shit it involves nickel and I'll be surprised if it doesn't involve chromium.

[husaberg]

Apologies, I meant "whatever shiney stuff they're electroplating onto alloy bores nowadays", rather than actual simple chrome.

I'll read that wee article when I've got half an hout to figure out how to size it so I can see it and have it STAY that size. However, I'll bet you a pound to a pinch of shit it involves nickel and I'll be surprised if it doesn't involve chromium.

click on it click again until to see an magnifying glass with a + and click again like magic...........
the one below has already been resized so just click.
Do all engineers have beards and Glasses?:)
http://img2.toysperiod.com/img/cache/7a/800x600/d4e4o5g414n3y4046416q4q2b4x2r2h4v5f4042354v2r294x2 u2.jpg

[Ocean1]

click on it click again until to see an magnifying glass with a + and click again like magic...........

Cool, cheers, it even works :laugh:

And nicasil = nickel and silicone, whoda thought?


Do all engineers have beards and Glasses?
http://img2.toysperiod.com/img/cache/7a/800x600/d4e4o5g414n3y4046416q4q2b4x2r2h4v5f4042354v2r294x2 u2.jpg

That's Masons innit? Nearly the same I suppose.

[pete376403]

...As an aside i see the new Yamaha 150 or 125 four stroke road bike has a non coated alloy cylinder with i believe a very high silicon content.

Google Chev Corvair Flat 6. In 1960 they were using a high silicon content aluminium for the block, after finished to size it was etched in some way, the ali was eroded leaving peaks of hard silicon for the rings to bear on. I guess the patent must have expired...

Another variation was Kawasaki Electrofusion. What I read (Kevin Cameron) said it involved a very high voltage applied to a wire of some material down the centre of the cylinder. The wire would 'explode" driving the material into the aluminium

[husaberg]

Google Chev Corvair Flat 6. In 1960 they were using a high silicon content aluminium for the block, after finished to size it was etched in some way, the ali was eroded leaving peaks of hard silicon for the rings to bear on. I guess the patent must have expired...

Another variation was Kawasaki Electrofusion. What I read (Kevin Cameron) said it involved a very high voltage applied to a wire of some material down the centre of the cylinder. The wire would 'explode" driving the material into the aluminium

i wasn't aware of the Corvair but i had heard the same re the Kawa electrofusion.
The idea behind the Idea of the screw in liner iron was to achieve reasonable thermal propertied without the cost of plating/coating plus the molds i have are designed around a 54mm, not a major issue but i was trying to keep costs down to a affordable level for the masses. Also to avoid the hassle of multiple mold changes.
This is the Yam system (http://www.yamaha-motor.co.jp/global/news/2002/07/31/innovation.html)
The article i had linked had the squuze form liners that the same company did years before Yamaha as well but i think they still had a coating of some sort

http://etalkindia.com/talk/automobiles-review-road-tests/1556-new-yamaha-yzf-r15-review-pictures-specification-150cc-bike.html


Also, Yamaha has implemented new DiASil Technology which makes engine more efficient in power handling. DiASil Cylinders are all-aluminum cylinders made by YAMAHA’s proprietary aluminum die casting technology. An aluminum alloy with 20% silicon content is used to create a very hard, reliable cylinder surface, making conventional iron sleeves obsolete. As a result, the entire cylinder can be made of aluminum, a better conductor of heat, which means the cylinder delivers better heat dissipation and less weight. (Aluminum’s heat conductivity is 3.1 times that of iron.)

http://www.yamaha-motor.co.jp/global/news/2002/07/31/innovation.html

YZF R15 makes use of DiASil (Die-casting Aluminum-Silicon) cylinder. The DiASil Cylinder is an all-aluminum cylinder made possible by an exclusive Yamaha aluminum forging technology. Because it uses a 20% silicon aluminum alloy, it is possible to create a cylinder wall that is so hard and durable that it eliminates the need for a conventional steel cylinder sleeve. And, because the cylinder is all aluminum, it has excellent heat dissipation qualities (cooling capacity is improved by 60% and reduces engine weight (by 30%) at the same time.http://www.vicky.in/straightfrmtheheart/yamaha-yzf-r15-150cc-pictorial-preview/

[Grumph]

Reading material - anything by Pil Irving. I do keep coming back to him but as someone said, the old B was right more often and earlier than most....

The problem you face is that 99% of the methods that have been invented for bore linings - transplant coatings, trick cylinder materials, whatever, are intended to make mass production cheaper. Hence they are both capital intensive and plant intensive - ie, they cost a lot to set up and need f'n big bits of gear to do....

The low volume one off - or say less than 10,000 unit production run is still best served with the simplest methods...
Sand cast barrel, parallel iron liner shrink fitted....

Ask NZ Cylinders in Ashvegas for a price...then ask someone with a lathe to turn up a plain liner for you...
Or just keep buying the lotto tickets, your choice.

[bogan]

Any good ways to glue nitrile rubber to aluminium for long term use exposed to fuel?

[Ocean1]

Any good ways to glue nitrile rubber to aluminium for long term use exposed to fuel?

I've used 3M scotch-weld 847 to glue fuel tank gaskets on with some luck.

Probably good to deal with any aromatics lurking on the surface of the rubber first.

[bogan]

I've used 3M scotch-weld 847 to glue fuel tank gaskets on with some luck.

Probably good to deal with any aromatics lurking on the surface of the rubber first.

Mint, and best way to remove aromatics? just wash em and dry em good or are chemicals needed?

[husaberg]

Mint, and best way to remove aromatics? just wash em and dry em good or are chemicals needed?

there is a thread I posted about a guy who made inlet manifolds (reed rubbers) at home for a RD somewhere.

https://www.youtube.com/watch?v=-zKdDgzWDms&list=UUAuEjSGU8jtXJE_srB4YazA
he describes the whole process on a page somewhere.....

[Grumph]

Any good ways to glue nitrile rubber to aluminium for long term use exposed to fuel?

There's at least one place in ChCh who can vulcanise same. Try the yellow pages local to you for rubber bits makers - rollers etc.

[Ocean1]

Mint, and best way to remove aromatics? just wash em and dry em good or are chemicals needed?

MEK from memory, and I roughed the surface up a bit with emery tape just for the hell of it.

Lookie here: http://multimedia.3m.com/mws/mediawebserver?mwsId=66666UF6EVsSyXTtnxf2oxs6EVtQE Vs6EVs6EVs6E666666--

[Ocean1]

there is a thread I posted about a guy who made inlet manifolds (reed rubbers) at home for a RD somewhere.
...

What on earth is he using?

I've done similar with potable silicone. In fact there's several litres still under a bench here somewhere that must be close to the end of it's shelf life...

[husaberg]

What on earth is he using?

I've done similar with potable silicone. In fact there's several litres still under a bench here somewhere that must be close to the end of it's shelf life...

Rubber... There is or was a thread where he datails it throughly more likely a RD yamaha forum one i guess, If you google his user name it might pop up.
I was surprised how quick i found the video. They look very professional right down to the parts numbers......

http://www.precisiontradingsystems.com/inlet_manifolds_hows_its_made.htm

[Seraph]

Would 40nb Apl5l bgrade seamless sch80 suffice for fork legs strength wise?

[Grumph]

Would 40nb Apl5l bgrade seamless sch80 suffice for fork legs strength wise?

what wall thickness is it going to finish up - and what end use ? street or motocross ?

from memory that's pretty close to what Ceriani used for stanchions back in the day.

Edit - on thinking a bit more, what surface finish are you planning on ? ideally the sequence is, grind, hard chrome, finish grind...but you want something which doesn't suffer badly from hydrogen embrittlement - and that I don't personally know about this material. Suppliers should have that info, along with any suggested heat treatments to remove the hydrogen.

[Ocean1]

Would 40nb Apl5l bgrade seamless sch80 suffice for fork legs strength wise?

What's important for forks is that the stanchions are stiff, and all carbon steels have pretty much the same elasticity. Ultimate elastic limits are almost irrelevant, well before you bend them anywhere near that the tube has distorted more than the clearance between the stanchions and the sliders and they've seized, dramatically increasing load.

So the trick is to specify tube diameter and wall thickness that will take the load of your intended design and use without distorting that much. You can work that out, but to be honest my attempts rarely describe what happens in the real world. It's just easier to look at what works in similar equipment and start from there, let Mr Honda pay for the hundreds of iterations required to get it right.

Having said that once you've figured out the dimensions req'd the extra cost of 4130 chromoly isn't much beside the cost of making them.

If you want to try anyway these are the numbers you probably need to use: 300649


what wall thickness is it going to finish up - and what end use ?

Several times over the years I've bought fork stanchions to use for completely unrelated projects simply because it's a known quantity and quality. In fact in one instance the prototype led rapidly to an order for about 20 units, asap. I had all sorts of trouble trying to explain an order for 20 Honda XR400 fork stanchions.

[Seraph]

I should have mentioned this will be for rear legs on a springer around about 1300 long, 4130 would have been ideal but my triples for this set are a rather funny diameter. I wanted plenty of material to turn down and still leave some beef..
I know the numbers but in a real world situation I honestly dont know what id be looking at in terms of pressure and stress put on them.. I can design machine and weld but when it comes to the math im a little lost

[Ocean1]

I should have mentioned this will be for rear legs on a springer around about 1300 long, 4130 would have been ideal but my triples for this set are a rather funny diameter. I wanted plenty of material to turn down and still leave some beef..
I know the numbers but in a real world situation I honestly dont know what id be looking at in terms of pressure and stress put on them.. I can design machine and weld but when it comes to the math im a little lost

Join the club. :laugh:

I like leading link setups for that application though, standard forks at that length on that much rake have too much stiction.

I'd have thought there would be plenty of technical data available on US chopper sites though, no?

[Seraph]

Join the club. :laugh:

I like leading link setups for that application though, standard forks at that length on that much rake have too much stiction.

I'd have thought there would be plenty of technical data available on US chopper sites though, no?

There's some, but nothing in the diameter range im looking at (50mm..) most of the build material seems to be DOM or good ol erw..

[Grumph]

There's some, but nothing in the diameter range im looking at (50mm..) most of the build material seems to be DOM or good ol erw..

which says something too....

You could check it the good old rough way...take a 2G bump load at the axle and multiply it by say 4 for the load adjacent to the bottom triple clamp. Tube specs should give you the yeild point. If the calculation is less than the yeild stress, she'll be sweet.

Load on front wheel (laden, worst case scenario) at a guess 200Kg (rough guess...) X 2G = 400. Times 4 equals 1600Kg at the bottom triple...Divided by the two tubes is 800Kg each. This is bump case - not running into a wall....

A good quality 50mm OD tube shouldn't bend at that...And given it's a springer, at least some of the loads will be taken higher up the tube rather than reacted at the axle - which will reduce the loads too.

[Brian d marge]

If its for the rear tubes on a springer , ya dont need anything fancy. It isnt a sliding surface so you dont need a Hard finish.

From Memory a mild steel DOM would be fine ,I will check though , Remember Stiffness is a product of size not material, The reason why USD forks are large dia but very thin wall thickness

Finally if you are building springers , the americans have been there done that , there are a few plans already on the net ,

Stephen

[Ocean1]

which says something too....

You could check it the good old rough way...take a 2G bump load at the axle and multiply it by say 4 for the load adjacent to the bottom triple clamp. Tube specs should give you the yeild point. If the calculation is less than the yeild stress, she'll be sweet.

Load on front wheel (laden, worst case scenario) at a guess 200Kg (rough guess...) X 2G = 400. Times 4 equals 1600Kg at the bottom triple...Divided by the two tubes is 800Kg each. This is bump case - not running into a wall....

A good quality 50mm OD tube shouldn't bend at that...And given it's a springer, at least some of the loads will be taken higher up the tube rather than reacted at the axle - which will reduce the loads too.

Aye, in fact around half the normal suspension axle load will be on the front compression rods, so that'd be well conservative.

In which case 50mm sounds big, (given a couple of mm wall thickness), and I don't remember having seen a springer front end main tube that big.

Edit: was looking for examples and came across this: http://www.tonyfoale.com/Articles/Steer/STEER.htm

[Seraph]

Well by the sounds of it I should be fine.. 50mm is more of a aesthetic choice than function.. well ill get everything turned down monday and see how it does

thanks!

[bogan]

There's at least one place in ChCh who can vulcanise same. Try the yellow pages local to you for rubber bits makers - rollers etc.

So, the shit I got locally isn't very fuel safe and has turned to shit. Who are the guys in ChCh, a good recommendation is well worth the shipping there and back... Figure I can just machine a pocket into the bit of ali they now sit against and get it vulcansied in there for a permanent solution.

[Grumph]

So, the shit I got locally isn't very fuel safe and has turned to shit. Who are the guys in ChCh, a good recommendation is well worth the shipping there and back... Figure I can just machine a pocket into the bit of ali they now sit against and get it vulcansied in there for a permanent solution.

Conveyor Belt specialists in ChCh were one of the places I meant. The other was a little place round the corner from Mace eng who seem to have disappeared post quakes. Local to you i'm sure there's a conveyor belt place who can do vulcanising. Again, check your local yellow pages for rubber products places.
I've only just realised my favourite small outfit referred to above has gone. Bugger it - they did all sorts of little bits of rubber mounts. very useful.

[husaberg]

Conveyor Belt specialists in ChCh were one of the places I meant. The other was a little place round the corner from Mace eng who seem to have disappeared post quakes. Local to you i'm sure there's a conveyor belt place who can do vulcanising. Again, check your local yellow pages for rubber products places.
I've only just realised my favourite small outfit referred to above has gone. Bugger it - they did all sorts of little bits of rubber mounts. very useful.

I had a tiki tour around central city last week there is so much stuff gone, it was bloody hard to navigate at all, with few landmarks.
Where I used to live (The old Para building), where I used to work Whiting's, Where I used to drink, where I used to get my lunch... all gone

[Grumph]

I had a tiki tour around central city last week there is so much stuff gone, it was bloody hard to navigate at all, with few landmarks.
Where I used to live (The old Para building), where I used to work Whiting's, Where I used to drink, where I used to get my lunch... all gone

Yep, all the places i worked in the central city, gone. Navigation as you say is hard because you didn't look for street names, you turned at such and such a shop....
problem for the last couple of years has been that you'd find where someone had relocated to, get it programmed into the mental directory, then that place would be demolished. i'd like to ask an engineer just why some of them were demolished too...But as we see here you'd do better to ask a politician.

[Reubix]

Heya team

If I want to get a consistent 12v to my motorbike (as all I have is a dead battery and a battery charger) just to test the electrics is there any way I can do this?

IE Can I have my battery connected to the bike then have the battery charger constantly running to keep it topped up while running the electrics of the bike (without blowing anything)

[Grumph]

Personally, if it's a known bad battery, I'd just hook the battery charger on to the wire terminals of the bike's harness. That should let you test most circuits.
It may not be grunty enough to fire the bike so borrow a decent battery - parent's/girlfriend's/own car will do - and jumper lead it in to the harness.

[Reubix]

Personally, if it's a known bad battery, I'd just hook the battery charger on to the wire terminals of the bike's harness. That should let you test most circuits.
It may not be grunty enough to fire the bike so borrow a decent battery - parent's/girlfriend's/own car will do - and jumper lead it in to the harness.

So connecting a battery charger directly to the bike wont do any damage to it? Should I measure anything with a multimeter first or nay?

[Grumph]

So connecting a battery charger directly to the bike wont do any damage to it? Should I measure anything with a multimeter first or nay?

I've yet to see a modern charger which puts out more than about 2 - 3 amps. You shouldn't damage anything at that.

[Yow Ling]

Fort Rubber company, gone to auckland
Rubber mouldings in Walker street , I saw the sign on the building , dont know if they are still there
Thorndon rubber in wellington ( I think thats their name) do alot of printing machine rubber rollers

[Reubix]

I've yet to see a modern charger which puts out more than about 2 - 3 amps. You shouldn't damage anything at that.

This thing puts out 4 apparently...

[Akzle]

This thing puts out 4 apparently...

what's the smallest fuse in your box? 10?

[Grumph]

Fort Rubber company, gone to auckland
Rubber mouldings in Walker street , I saw the sign on the building , dont know if they are still there
Thorndon rubber in wellington ( I think thats their name) do alot of printing machine rubber rollers

Thanks Mike - I should have remembered flexographic printing rollers and mentioned them as a possible vulcanising source. Rubber Mouldings don't seem to be in the book any more. I'd assumed that meant gone - but i suppose I'd better have a look next time I'm past.

[Reubix]

what's the smallest fuse in your box? 10?

Ay, it is indeed littered with 10 amp fuses

[ducatilover]

Is there any reason why I should not run bronze as the wheel spacers on my bike?
It looks pretty

[bogan]

Is there any reason why I should not run bronze as the wheel spacers on my bike?
It looks pretty

I can think of one, but I'm not sure 'cos you should be polishing that guy's frame' is the sort of answer you are looking for :bleh: Probably not too good for galvanic corrosion with the ali either...

Also, pics required.

[Grumph]

Is there any reason why I should not run bronze as the wheel spacers on my bike?
It looks pretty

If you like bronze, why not use gold ? It's only marginally softer and a tad heavier....

[ducatilover]

I can think of one, but I'm not sure 'cos you should be polishing that guy's frame' is the sort of answer you are looking for :bleh: Probably not too good for galvanic corrosion with the ali either...

Also, pics required.
Galvanic corrosion eh? lol I need moar corrosions bro :lol:


If you like bronze, why not use gold ? It's only marginally softer and a tad heavier....

Jeez I can't afford to be that silly :(

I like the look of it, had some bronze bushes given to me by a mate and I think they'd look boss as spacers.
If it's softer than the Suzuki alloy cheese I won't use it, and I'll cry a little

[Ocean1]

Galvanic corrosion eh? lol I need moar corrosions bro :lol:



Jeez I can't afford to be that silly :(

I like the look of it, had some bronze bushes given to me by a mate and I think they'd look boss as spacers.
If it's softer than the Suzuki alloy cheese I won't use it, and I'll cry a little

If they're off-the-shelf nominal dim bushes they're possibly sintered bronze. Great for bushes, holds a bit of oil and wears well. Shite compression strength. Probably no worse than the alloy spacers on most modern machines though.

[ducatilover]

They're something he turned up for a job but didn't need, so not too sure what exact flavour they are.
It's not for a modern thing, it's for my GNthing

[Imagineering]

Is there any reason why I should not run bronze as the wheel spacers on my bike?
It looks pretty


Someone mentioned electro-galvanic corrosion. Not a problem with Bronze, don't use Brass though. Many pieces of Equipment have Aluminium Cast around Bronze then reamed to suit.

One of the Posters above has a good point regarding Sintered Bronze Bushes not having good Compressive Strength. Solid Bronze however, has a greater compressive strength than Aluminium Alloy.

[ducatilover]

Someone mentioned electro-galvanic corrosion. Not a problem with Bronze, don't use Brass though. Many pieces of Equipment have Aluminium Cast around Bronze then reamed to suit.

One of the Posters above has a good point regarding Sintered Bronze Bushes not having good Compressive Strength. Solid Bronze however, has a greater compressive strength than Aluminium Alloy.

:woohoo: Cheers. I'll look in to turning some up. Got to have sexy cheap parts

[Luckylegs]

I'm sure you lot will have machinery using these or have had in the past. I have just bought an old lathe and am in the process of cleaning, lubing and all that stuff. I've cleaned up the drip oilers but the leather washers on those have seen better days and need to be replaced. I'm not too old that I can say I've never seen a leather washer before so don't know whether there is anything particularly magic about its use or rather it was what was available and affordable in a bygone era

My question - Can I replace with Fibre (or rubber I suppose) and should I ?

[Akzle]

I'm sure you lot will have machinery using these or have had in the past. I have just bought an old lathe and am in the process of cleaning, lubing and all that stuff. I've cleaned up the drip oilers but the leather washers on those have seen better days and need to be replaced. I'm not too old that I can say I've never seen a leather washer before so don't know whether there is anything particularly magic about its use or rather it was what was available and affordable in a bygone era

My question - Can I replace with Fibre (or rubber I suppose) and should I ?

i can't visualise them in my head.


pipe cleaners.

you mean, oilers for the headstock bearings yes?

[Luckylegs]

i can't visualise them in my head.


pipe cleaners.

you mean, oilers for the headstock bearings yes?

Yep, oilers for the headstock bearings like in the picture
310365

The washers sit in the brass top and bottom caps to seal the plastic tube

[speights_bud]

Well so long as it holds the oil in side I don't see any problems

[Akzle]

Yep, oilers for the headstock bearings like in the picture

The washers sit in the brass top and bottom caps to seal the plastic tube

you have a set of hole punches yes?

just add a couple of "lace holes" to your bondage gear...


ps. that looks clean as hell. what are you cleaning??

pics or it didn't happen.

[Akzle]

sorry. pipe cleaners work in the cup-types, not so sure if they would in there...

[Ocean1]

I'm sure you lot will have machinery using these or have had in the past. I have just bought an old lathe and am in the process of cleaning, lubing and all that stuff. I've cleaned up the drip oilers but the leather washers on those have seen better days and need to be replaced. I'm not too old that I can say I've never seen a leather washer before so don't know whether there is anything particularly magic about its use or rather it was what was available and affordable in a bygone era

My question - Can I replace with Fibre (or rubber I suppose) and should I ?

Gaskets in the sight glasses? You can make them out of heavy gasket paper or cork. Or leather. Nitrile would be OK, but sometimes it slithers out from under the sealing faces. The trick is to not over-tighten them

The most reliable trick I've found is to make sure the faces are machined nice and flat and just use a thin smear of Loctite 518 or similar.

What's the lathe?

[Luckylegs]

you have a set of hole punches yes?

just add a couple of "lace holes" to your bondage gear...
[QUOTE]

There's no lace holes in gimp suits ???
[QUOTE=Akzle;11308448202]
ps. that looks clean as hell. what are you cleaning??

pics or it didn't happen.

Thet arent my ones, geez! just an example to give a idea of what i was on about

[Luckylegs]

Gaskets in the sight glasses? You can make them out of heavy gasket paper or cork. Or leather. Nitrile would be OK, but sometimes it slithers out from under the sealing faces. The trick is to not over-tighten them

The most reliable trick I've found is to make sure the faces are machined nice and flat and just use a thin smear of Loctite 518 or similar.

What's the lathe?

Not the sight glass (ie where you see the drip) but the resevoir above. Ill assume your advice applies anyway. Re what lathe it is. Not sure yet, i think its a colchester but it hasnt been confirmed. The previous owner didnt know and theres no naming or serial numbers visible.

One of these days ill get some photos up on the 'show us your lathe' thread and maybe the kb experts will be able to shed some light

Cheers

[Luckylegs]

Well so long as it holds the oil in side I don't see any problems

Yeh the leather ones are failing to do that unfortunately

[Akzle]

Not the sight glass (ie where you see the drip) but the resevoir above. Ill assume your advice applies anyway. Re what lathe it is. Not sure yet, i think its a colchester but it hasnt been confirmed. The previous owner didnt know and theres no naming or serial numbers visible.

One of these days ill get some photos up on the 'show us your lathe' thread and maybe the kb experts will be able to shed some light

Cheers

peruse lathes.co.uk

the most cohesive list i've yet.

get the tape measure out, i bet mines bigger'n' yours!

[Grumph]

I'll give you two modern options to replace the leather.
Sealing washers which are a steel washer with nitrile bonded on. Seal Imports carry a range and probably other places too.
Or make up replacements from urethane. I made up a set for a vintage Triumph rocker box which had pissed oil for ever. Top end is dry but of course the bottom end is still incontinent.

[husaberg]

Any good ways to glue nitrile rubber to aluminium for long term use exposed to fuel?

http://jbmindustries.com/aboutus.html

[bogan]

So, what the fuck is up with BSP? I've been contracted in to help out with a bunch of pipework, and different suppliers seem to have a different idea of what the S bit in BSP means.

And is there a decent alternative to stilsons? sick of seeing fucking stilson marks on the pipework coming out of that workshop.

[speights_bud]

So, what the fuck is up with BSP? I've been contracted in to help out with a bunch of pipework, and different suppliers seem to have a different idea of what the S bit in BSP means.

And is there a decent alternative to stilsons? sick of seeing fucking stilson marks on the pipework coming out of that workshop.
http://images.tapatalk-cdn.com/15/11/10/3932d50e40897b485feeb4c15e579d2a.jpghttp://images.tapatalk-cdn.com/15/11/10/2d0cb46da1f1d1ea76d7cc09ae863500.jpg

My 2 closest resources tell me that the S means standard. Which is what I have always understood.

Though it took me over a year to convince our manager that there is a difference between a BSP taper tap (starting type tap) and a BSPT tap.

We use 1/4 inch BSPT plugs for water galleries in injection moulds and they always leaked. He kept buying tapered BSP taps. Grrr.....

(Sorry if the images are huge. Using the phone and Tapatalk)

[husaberg]

So, what the fuck is up with BSP? I've been contracted in to help out with a bunch of pipework, and different suppliers seem to have a different idea of what the S bit in BSP means.

And is there a decent alternative to stilsons? sick of seeing fucking stilson marks on the pipework coming out of that workshop.
I always though BSP was British standard pipe?

edit that's what google says but not so standard in the best of British traditions. (it has different threads lol)
https://en.wikipedia.org/wiki/British_Standard_Pipe
As for the Wrench no doubt these just leave a different kind of mark.
317197

[schrodingers cat]

I always though BSP was British standard pipe?

edit that's what google says but not so standard in the best of British traditions. (it has different threads lol)
https://en.wikipedia.org/wiki/British_Standard_Pipe
As for the Wrench no doubt these just leave a different kind of mark.
317197

The 'S' in BSP is certainly 'standard'

However, since there are tapered and non tapered versions, the tapered gets referred to as BSP tapered (BSPT) and the non tapered version is sometimes called 'straight' leading folks to confuse themselves by referring to BSPS - which is incorrect. The non tapered (parallel) is actually BSPF.
The 'F' refers to 'fitting'
Reason being that usually, sockets are BSPF and nipples are BSPT.

This colloquial use of 'straight' may be the cause of confuzzlement

[bogan]

Yeh I know the S stands for standard, but some suppliers BSP fitting only get like 2 turns into another suppliers ones, and some go right over the top and are still sloppy as shit. Ie, in what fucking world is that standard.

And yeh I know there's BSPT and BSPP and BSP can mean eaither of those things, especially in sizes around 1-2in


Though it took me over a year to convince our manager that there is a difference between a BSP taper tap (starting type tap) and a BSPT tap.

We use 1/4 inch BSPT plugs for water galleries in injection moulds and they always leaked. He kept buying tapered BSP taps. Grrr.....

(Sorry if the images are huge. Using the phone and Tapatalk)

This makes sense, the guys I'm working for don't use any taps though, any female thread is purchased as a fitting. Do the BSPT taps leave a nunga on the thread when you bring the tap back out? or does the backside of the previous tooth clean that up pretty well?

[speights_bud]

Yeh I know the S stands for standard, but some suppliers BSP fitting only get like 2 turns into another suppliers ones, and some go right over the top and are still sloppy as shit. Ie, in what fucking world is that standard.

Yep i'm with you now. Probably shitty suppliers that are machining to different tolerances. Are the differing parts being locally made? or are they chinese shit/good euro quality?
It doesn't take much to go from tight to sloppy on a parallel thread. My guess is that a CNC just spits them out and no one gives a damn.

As you can see in the previous photo's, the 'standard' dimensions allow for no clearance on the threads.


This makes sense, the guys I'm working for don't use any taps though, any female thread is purchased as a fitting. Do the BSPT taps leave a nunga on the thread when you bring the tap back out? or does the backside of the previous tooth clean that up pretty well?

It cleans them up pretty well, but then again we only use the small taps. 1/4 and 1/8 for plugging off 12mm waterway galleries. Nothing big like 1-2inch.
I would expect most female threads above 1 1/2" would usually be turned in a lathe?

Your guys would be cutting their own male threads though wouldn't they?
Not that this makes any difference as the problem you are having is the "same shaft, sloppy in some holes but not others";)

[bogan]

Yep i'm with you now. Probably shitty suppliers that are machining to different tolerances. Are the differing parts being locally made? or are they chinese shit/good euro quality?
It doesn't take much to go from tight to sloppy on a parallel thread. My guess is that a CNC just spits them out and no one gives a damn.

As you can see in the previous photo's, the 'standard' dimensions allow for no clearance on the threads.



It cleans them up pretty well, but then again we only use the small taps. 1/4 and 1/8 for plugging off 12mm waterway galleries. Nothing big like 1-2inch.
I would expect most female threads above 1 1/2" would usually be turned in a lathe?

Your guys would be cutting their own male threads though wouldn't they?
Not that this makes any difference as the problem you are having is the "same shaft, sloppy in some holes but not others";)

It's a good brand name stuff, but perhaps they outsource down a little bit. The good news is it's all low pressure anyway. Anzor or S&T fittings seems to be the good shit, it'll only on the expensive stuff we attach to this (pumps, valves etc) that we have a few clearance issues.

Some appear to just be cast, the rest machined, but given the imbalance around that axis, it might be CNC thread milled.

Yeh, that's one thing I'm going to have to fix though, big tolerance in what they make, and what I spec them to make. Sure is, good thing the goop fills em up all the same...

[speights_bud]

You might have to make them some go-no go gauges. I've made a few up for the production dept. Made a big difference in overall quality

[bogan]

You might have to make them some go-no go gauges. I've made a few up for the production dept. Made a big difference in overall quality

Yeh that's a good idea, cheers.

[Grumph]

Yeh, that's one thing I'm going to have to fix though, big tolerance in what they make, and what I spec them to make. Sure is, good thing the goop fills em up all the same...

I used to call that electricians tolerances...1/2in hole to put a small wire through...the fact that plumbers use so much joint packing as routine will always count against better quality control.

[Ocean1]

Yep, if they don't fit at least one of 'em is out of spec. Go/No go guages is a good idea.

What rips my nightie is fucking plumbers and suppliers insisting on calling them "15mm BSP" :facepalm:

[bogan]

Yep, if they don't fit at least one of 'em is out of spec. Go/No go guages is a good idea.

What rips my nightie is fucking plumbers and suppliers insisting on calling them "15mm BSP" :facepalm:

Fuck I reckon, specially since most still have the 1-1/2" cast into the bloody side.

[F5 Dave]

The B stands for British. This probably goes a long way to explaining the tolerances and why some bits have to be matched to selected other bits. Its part of the standard and part of the licencing agreement, which is incidentally why the Germans didn't get accredited and begrudgingly had to follow the French lead which as you can imagine caused much grumbling and probably lead to the first and second world war.

[schrodingers cat]

Dear Bogan, now I understand.
Your questions aren't really questions are they? It's just a thinly veiled whinge.
Next time try a. Friday night rant thread b. Expressing yourself clearly
Here's a clue: starting by asking ' what the fuck...?' Is never going to open the door wide to positive and proactive communication.
But then, that was never the point anyway as per my initial observation.

[Ocean1]

The B stands for British. This probably goes a long way to explaining the tolerances and why some bits have to be matched to selected other bits. Its part of the standard and part of the licencing agreement, which is incidentally why the Germans didn't get accredited and begrudgingly had to follow the French lead which as you can imagine caused much grumbling and probably lead to the first and second world war.

Give 'em credit for more or less inventing "standards" though.

I recall an old tutor waxing lyrical on the topic of Mr Whitworth's invaluable system, whereby a cylinder made in Manchester, (maybe) could be fitted with a piston made in Leeds such that one could barely fit one's hand between them.

May have been some poetic licence involved but you get the drift.

[husaberg]

Give 'em credit for more or less inventing "standards" though.

I recall an old tutor waxing lyrical on the topic of Mr Whitworth's invaluable system, whereby a cylinder made in Manchester, (maybe) could be fitted with a piston made in Leeds such that one could barely fit one's hand between them.

May have been some poetic licence involved but you get the drift.

Pretty sure the poms invented the Poetic licence and the waxing lyrical as it helped sell more shoddy rust overnight Morris's and Austin's with MG and Woolsey badges.

[bogan]

The B stands for British. This probably goes a long way to explaining the tolerances and why some bits have to be matched to selected other bits. Its part of the standard and part of the licencing agreement, which is incidentally why the Germans didn't get accredited and begrudgingly had to follow the French lead which as you can imagine caused much grumbling and probably lead to the first and second world war.

True, and I guess the P is for what some operators must be on to achieve said tolerances while doing such a simple task.


Dear Bogan, now I understand.
Your questions aren't really questions are they? It's just a thinly veiled whinge.
Next time try a. Friday night rant thread b. Expressing yourself clearly
Here's a clue: starting by asking ' what the fuck...?' Is never going to open the door wide to positive and proactive communication.
But then, that was never the point anyway as per my initial observation.

Yet, I received quality answers from the other respondents, as was the point. So perhaps you can fuck off and get a clue (veil thin enough, and expression clear enough for you?) before being so quick to whinge about how I choose to phrase my question.

[Brian d marge]

Give 'em credit for more or less inventing "standards" though.

I recall an old tutor waxing lyrical on the topic of Mr Whitworth's invaluable system, whereby a cylinder made in Manchester, (maybe) could be fitted with a piston made in Leeds such that one could barely fit one's hand between them.

May have been some poetic licence involved but you get the drift.

and its a damn good thread form too!

[schrodingers cat]

Yet, I received quality answers from the other respondents, as was the point. So perhaps you can fuck off and get a clue (veil thin enough, and expression clear enough for you?) before being so quick to whinge about how I choose to phrase my question.

Jolly good.
I think my fuck off has more class than yours but it's only ever opinion and it is the Internet after all.

[bogan]

The B stands for British. This probably goes a long way to explaining the tolerances and why some bits have to be matched to selected other bits. Its part of the standard and part of the licencing agreement, which is incidentally why the Germans didn't get accredited and begrudgingly had to follow the French lead which as you can imagine caused much grumbling and probably lead to the first and second world war.

Anyone know a good source for exhaust parts? off the shelf tube bends, weld flanges/fittings, mufflers (complete or as parts); one to do for the bike, one for the car.

[nzspokes]

Segidins auto parts. Spelt wrong but they have a lot of that stuff.

http://www.segedins.com/

[husaberg]

Anyone know a good source for exhaust parts? off the shelf tube bends, weld flanges/fittings, mufflers (complete or as parts); one to do for the bike, one for the car.

I have always had good luck with the local muffler shop they are happy to sell off the shelf preformed mandrel bends.
If you want something a little more exotic maybe try Wobbly he has a program to spit out rather nice pipes that are made in sections and are able to be directly laser cut.
Pretty sure its compatible with solid works.
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=303419&thumb=1&d=1329805127
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=303419&d=1413021847
They end up like this, Although he is a two stroke guy, he designed the Britten pipes

http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=319503&stc=1&thumb=1&d=1455308276
http://www.kiwibiker.co.nz/forums/attachment.php?attachmentid=283669&stc=1&thumb=1&d=1370295836

https://www.youtube.com/watch?v=FZ8CGGYamuE
Failing that maybe consider hydroforming them. (Bike not the car)
http://www.kiwibiker.co.nz/forums/showthread.php/176280-Designing-and-manufacturing-of-exhaust-pipes
That's what Pete Gibson used to do for the SOS racers in the nineties

[Ocean1]

I have always had good luck with the local muffler shop they are happy to sell off the shelf preformed mandrel bends.

That's it. I used to go burgle the local pit stop scrap bin, and anything I needed that wasn't there I'd simply buy off their rack. Their discounts with suppliers are so good they can make good beer money from me at prices I can't match going straight to S&T or any other principal.

Except donuts, a guy in Lower Hutt makes them, I buy them straight from him but places like TWL stock them at almost reasonable prices.

Having said that it's been a couple of years since I made anything out of zorst choob. I'm so used to using stainless if I had to make a pipe for a bike or a car I think I'd just use 304...

[husaberg]

That's it. I used to go burgle the local pit stop scrap bin, and anything I needed that wasn't there I'd simply buy off their rack. Their discounts with suppliers are so good they can make good beer money from me at prices I can't match going straight to S&T or any other principal.

Except donuts, a guy in Lower Hutt makes them, I buy them straight from him but places like TWL stock them at almost reasonable prices.

Having said that it's been a couple of years since I made anything out of zorst choob. I'm so used to using stainless if I had to make a pipe for a bike or a car I think I'd just use 304...

I think one of the few places I found that had the donuts was in Welly. Likely the same guy.
There was a thread me and Grumph posted in about them but I can't recall where it was (it might even have been this one)
I think the thread was someone looking for stainless bends and MS donuts
Stainless is for pussies, my Berg pipe is made of Inconel and Ti and CF hangers. I would hate to think what it cost.