Forced induction 100cc

[husaberg]

I am thinking that the gears out of motorbike gearbox or the likes would be a supply of easy to find gears failing that I have found 2 suppliers of Spur gears

https://sdp-si.com/

http://www.wmberg.com/

hoping to have some luck there.

Once I get all the parts that I will no be manufacturing I can then design around them to create the best possible supercharger for cheap!

Some gears and shafts for the initial here Rob mentioned they were like $8 each.
It a big cattle dog have a fer-it arround:yes:
http://www.ncy-motor.com.tw/product3.php?lang=en&car=&car2=&car3=&search=&page=13

[Ocean1]

At the moment I am just looking through gears and different options.

Worth talking to New Age Materials Computer Wreckers, they've usually got boxes of gears from wrecked mainframe hardware. At 226 Gracefield Road in Seaview.

Actually, worth a wander around their stock anyway, in a couple of years you'll be working on a completely different project and you'll be wondering where to get your hands on a certain widget and...

[husaberg]

Confession here
When i was thinking of doing something similar i tore apart a few angle grinders (i was thinking of mounting a few together)
I never actually put them back together either. the planetary gearbox is a much better solution of course.

[Sketchy_Racer]

Ok, so I have pulled the charger apart after running for a total of 30min, interesting to say the least and a lot of info gathered to improve the final design. Im just going to put some rubbish in here while it's fresh on my mind.

1: The length of the turbine shaft is critical. If the unsupported end is to far away from the bearings, at 200000 RPM the shaft will flex considerably causing severe damage to the impeller. It will still make boost however

2: Fluid drag if not controlled will cause the temperature to sky rocket incredibly fast, having the correct amount of oil is key

3: The outer ring needs to have parallel walls and cannot be a cup. The support at the bottom of the cup will cause the expansion to release contact at the end closest to the impeller and let the impeller float excessively.

4: 4 driving dogs at a small diameter are not enough, the shock loading of the on/off throttle will cause them to shear off leaving only one behind. A sprag clutch will help immensely with this problem, so will incorporated into the next
design

5: Phosphor bronze gears that are only 5mm thick are not enough to use as the change gears, the teeth will deform. An increase in width will help but precision ground gears would be better but add excessive cost, will look into options

6: Some form of seal on the turbine shaft is required, oil migration will happen despite having a vacuum pump draining oil out. A labyrinth seal may be the best solution here.

7: An internal oil pump and external reservoir, cooler and filter will make a big difference to thermal efficiency = More clean boost

But, the important part is that the rollers, shaft and outer ring had no signs of damage at all! This was the main objective with this budget test.

Anyway, I am about to start the conceptual design of Version 2

[Sketchy_Racer]

So after quite some time and a couple of other bike builds, its about time to get back into this.

I am going to start by cheating and using a AMR-300 Supercharger to start with and develop the bike/motor. Then as time allows I will continue on with the development of the small centrifugal supercharger.

Kyle managed to find a supplier of the small superchargers here

http://www.kemotorsport.com/

It was $280AUD including shipping for a good condition second hand or an extra $100 for a new one.

I'm hoping this week to have the bike running again and get some base runs and tuning done on the dyno without the supercharger so I have something to compare with

[Ocean1]

Excellent!

Gears. Don't die grinders have epicyclic reducers in them? Sometimes multiple sets? Be a cheap set of gears if they were man enough for the job...

[Sketchy_Racer]

The AMR300 Turned up and I've started learning the ropes on the Ecotrons EFI. Kyle and I put the charger on the bike and threw a belt on it, knowing that the ratio would be all wrong but thought it would be a laugh to start it up. Around 30psi while kicking it over. Might be a bit much perhaps.

I hoping that by running this charger nice and slow it will help with intake air charge temps!

[TZ350]

This is a great project, I am following it with a lot of interest, looking forward to a video of it, mostly so I can hear the sound of a supercharged 4T again, awesome.....:banana:

[Sketchy_Racer]

Yeah it's a cool project. Not without frustrations though. Spent all last night on the dyno trying to get a good base run on the motor before adding boost. managed a pathetic 7HP at best. Super flat curve which is good as the motor is only a 4 speeder. I really want to get the motor up around 10HP before I get the scharger on there but that might be a little optimistic.

Learnt last night about the VE and Alpha-N tables and where they work in relationship to the CUR_TpsUnTp_N So spent most of last night adjusting fueling in the VE table to ge no response in the engine! Oh well know that now I suppose.

Back to the dyno!

[speedpro]

If you are messing with the VE table adjust the software so the system uses the VE table for anything under say 95% throttle. That way you can be sure that changes to the cell values are valid. Then when you want to adjust the TPS table set the software so anything more than 10% throttle causes it to switch to the TPS table. Later you can set the switchover point to where it works best. My opinion now is that we need to use the autotune feature after we get it running more or less right. There is still some doubt about autotune results and where they are stored, which table, and exactly what happens when you switch to tuner desired lambda. It seems the autotune feature attempts to achieve lambda=1.

[husaberg]

http://www.youtube.com/watch?v=mrnul6ixX90


http://www.youtube.com/watch?v=rYlP5TEKf2w

[Sketchy_Racer]

Well, still no improvments, got 6.8hp on my dyno. (that would be around 7.5hp on a dyno jet) But then the fuel pump gave up. I pulled it apart but seems it's done its dash. It's been sitting in the trailer for over 6 months and its got water inside it.

I've got a pump off of a 600 here that will do. I also need to consider getting a adjustable pressure regulator to offset the boost pressure so the little pump from ecotrons might not have been up to it.

Seems that with the pitbike motor high HP levels are right out the door, at the point where I wonder if I keep wasting time with it or look elsewhere.

[Drew]

Well, still no improvments, got 6.8hp on my dyno. (that would be around 7.5hp on a dyno jet) But then the fuel pump gave up. I pulled it apart but seems it's done its dash. It's been sitting in the trailer for over 6 months and its got water inside it.

I've got a pump off of a 600 here that will do. I also need to consider getting a adjustable pressure regulator to offset the boost pressure so the little pump from ecotrons might not have been up to it.

Seems that with the pitbike motor high HP levels are right out the door, at the point where I wonder if I keep wasting time with it or look elsewhere.

Got a GL 145 here. Tell ya what, you super charge it to satisfy your testing, then do it again on something you're allowed to run.

[mr bucketracer]

Well, still no improvments, got 6.8hp on my dyno. (that would be around 7.5hp on a dyno jet) But then the fuel pump gave up. I pulled it apart but seems it's done its dash. It's been sitting in the trailer for over 6 months and its got water inside it.

I've got a pump off of a 600 here that will do. I also need to consider getting a adjustable pressure regulator to offset the boost pressure so the little pump from ecotrons might not have been up to it.

Seems that with the pitbike motor high HP levels are right out the door, at the point where I wonder if I keep wasting time with it or look elsewhere.what does a standard fxr 150 put out on your dyno? on a dyno jet its 14.3 to 14.5

[quallman1234]

what does a standard fxr 150 put out on your dyno? on a dyno jet its 14.3 to 14.5

Hopefully less than 13hp. As thats what mine barely makes, mines got a exhaust/carb and some awfully crap porting.

Will put my mates one back on there again at some stage. Standard carb, just a underseat exhaust and jetted for no airbox. So pretty much stock.

[TZ350]

what does a standard fxr 150 put out on your dyno? on a dyno jet its 14.3 to 14.5

Yes std FXR150 14.5 ish on a Dyno Jet ... I would not try hotting up your engine, for my money I would lower the compression and retard the spark, 10 static + 10 advance and just keep adding pressure. Supercharged engines run best on low compression (6:1 ish) standard or less than standard cams with minimal or best yet no overlap. Anyway for what its worth, back in the day that is how I remember them being setup at work.

[pete376403]

Yes std FXR150 14.5 ish on a Dyno Jet ... I would not try hotting up your engine, for my money I would lower the compression and retard the spark, 10 static + 10 advance and just keep adding pressure. Supercharged engines run best on low compression (6:1 ish) standard or less than standard cams with minimal or best yet no overlap. Anyway for what its worth, back in the day that is how I remember them being setup at work.

The volume of air delivered by the super / turbo charger is more useful then boost pressure. ie more air available = more fuel burned = (hopefully) more power.
Although, I've never done anything with mechanically supercharged engines, only turbocharged.

[Grumph]

when i did the Roots blown F3 500 kawa twin, we ran 9:1 on methanol. The guy whose rolling road we used had a mate who was building Penskes Cosworth turbos at the time. We sent him the details of bore,cams, valve sizes etc and he came back and said, you're on the right track. made around 110 at the wheel with 15lb boost.
Now this was a 74mm bore with big squish areas...with the little 2 valver your problem is the chamber shape and getting it to burn.
Not a lot you can do without playing with crown shapes - on forged pistons...

A good look at the budget may suggest starting with something more suitable.

[TZ350]

Again this is only as I remember it from way back when .... but I would not be worried about the four speed gearbox, because a positive displacement supercharger provides a massive torque increase everywhere and at any rpm. So the engine will pull like a tractor from low down and rev right out. Even on a mild cam it will rev till the valves bounce.

But I would be worried about the engines cooling. The little motors air cooling might be adequate for 7-10hp but with the supercharger you will need to be shedding double or triple that. Water methanol (or acetone so as to stay legal) injection might be the go. And maybe a big oil cooler and supplementary electric pump to shift a lot of extra engine oil through the radiator.

I think it can be done, its a very interesting project and am a little jealous..... :sick:

[Sketchy_Racer]

Yeah it's a interesting project for sure, with a load of hurdles to get over with the pitbike motor.

I think I will carry on with the pitbike motor, purely for the fact that I have it and it will be interesting to see what gains I can make with it.

I'll have a look around for a 3valve head for it, Im just not sure if they will fit into the 100cc bore.

Next job is to pull the motor out of the frame and improve the engine mounts as well as make the supercharger cradle and tensioner.

[Brian d marge]

You will have trouble with crankcase flex and head stud stretch
This and some ther stuff will limit how much you can shove into the motor
Stephen

But it needs to be done

Sent from my SC-01F using Tapatalk

[TZ350]

You will have trouble with crankcase flex and head stud stretch


I do remember the methanol engines on the dyno. They had the water galleries between the block and head plugged, the water was feed by a hose from the back of the block to the back of the head. no head gasket, but Copper "O" rings around the bores and heavy studs, steel backs on the main bearing caps. Under full boost you could see the fumes jetting out from the head/block joint. Steam from the water boiling in the brake. And the noise from the exhaust, induction roar, scream of slipping drive belts, all like a mad women possessed at 9,000 rpm......... so exciting, wet my pants when the BDA snapped a cam.

[Grumph]

Yeah, our limiting factor in the end was the head walking on the barrel. i really should have dry decked it but the owner called enough...

If you do find a 3 valve head, use the 2 valve side for exhaust and the single for inlet. reverse of naturally aspirated applies - easy to get the mixture in so only one inlet needed but the smaller twin exhausts will stay cooler. To encourage cooling, use a lot of overlap. i know it's not popular due to perceptions of lost boost but the extra flow through the valves at overlap provides a welcome cooling effect.

With full house unblown cams on the blown motor the torque was unbelievable. After we got it percolating properly, I seriously considered pulling gears out of the box - six speeds was hard work, three would have been perfect. BTW the cams were the same as Tony McMurdo's winning pink Kawa - a shitload of overlap.

toluene is your friend in the fuel.....

[speedpro]

I dry decked my Z1 turbo by fitting external oil lines to the head. Even with HD studs, steel orings, and coated copper head gaskets it was difficult to get the head gasket to seal. We sprung a small oil leak in the starter motor area at Taupo once when we were pissing round with 19lbs boost on an 1166cc motor. When I pulled it down it had a crack in the #2 mainbearing cap part of the lower crankcase. The crack extended to the outside which is where the oil was coming from. Had it welded and I hand filed it back to size. If the motor is a bit "budget" it is going to try and pull itself apart. You might want to machine up some sort of girdle top and bottom with HD studs between to keep it together tight. I used stock Z1 cams degreed with a bit more overlap. Cooling was a big problem. Standard unleaded pumpgas has about 30% toluene so that and some methanol with acetone to blend should be good.

[Brian d marge]

The cooling comes from the change of phase from a liquid to a gas and the mire you can get that to happen in the squish flame front area the more stable the combustion and the higher pressures you can run
Apart from beefing up crankcases and studs waste heat transfer one method of reducing head walk was to have a raised lip around the bore lapped into a groove around the head combustion chamber ,. Cant think of the name applied to this method .dry no gasket and as smooth and as flat as u can get it
Possible on a 4cyl easy on me single enfield hahahaha

Stephen

Sent from my SC-01F using Tapatalk

[husaberg]

The cooling comes from the change of phase from a liquid to a gas and the mire you can get that to happen in the squish flame front area the more stable the combustion and the higher pressures you can run
Apart from beefing up crankcases and studs waste heat transfer one method of reducing head walk was to have a raised lip around the bore lapped into a groove around the head combustion chamber ,. Cant think of the name applied to this method .dry no gasket and as smooth and as flat as u can get it
Possible on a 4cyl easy on me single enfield hahahaha

Stephen

Sent from my SC-01F using Tapatalk

the word ya looking for Stephen is "Spigot"

[Brian d marge]

Thats the one . .im tapping this out on a phone in the middle of a storm in north canterbury
So not near my books and a very dodgy memory.

Sent from my SC-01F using Tapatalk

[husaberg]

How long are you here Stephen..........

[speedpro]

The cooling comes from the change of phase from a liquid to a gas and the mire you can get that to happen in the squish flame front area the more stable the combustion and the higher pressures you can run


Oddly we went the other way with my turbo and reduced the squish area as much as possible. The only remaining squish area was next to the inlet valve. A mate had experimented with this sort of thing and determined that this was the go. The added advantage was that doing it reduced the compression. Whatever, when it was all going good it made more power than you could use even at Puke' except at the end of the back straight.

[Grumph]

Oddly we went the other way with my turbo and reduced the squish area as much as possible. The only remaining squish area was next to the inlet valve. A mate had experimented with this sort of thing and determined that this was the go. The added advantage was that doing it reduced the compression. Whatever, when it was all going good it made more power than you could use even at Puke' except at the end of the back straight.

yeah, there are some oddities with blown motors. Fuel mixing - as in well homogenised fuel and air - is very good, as is usually distribution. Very simple manifolding works pretty well. Personally I doubt if squish is as important in blown motors - but chamber shape definitely is. The more compact the chamber shape the better. It's hard enough to light the fire with high pressures - and a poor chamber shape just leads to even more advance...and more problems.
O ringing the bores in the usual style with 20G stainless wire helps too.

[Sketchy_Racer]

Loving all the input guys, I am reading it all. Next week I will be pulling the motor out of the frame as this week is busy now with other projects and im away this weekend. I've got access to some beryllium copper here so I am tempted to machine some valve guides and valve seats in a hope of controlling valve temps and I'll also degree the stock cam to get an idea of where that is. I like the idea of running a lot of overlap for valve cooling, esp in this case of such small valves and only 2 of them.

Out of curiosity, it makes me wonder how much power is lost through poor engine mounting. Obviously when an engine is vibrating in chassis that energy is coming from somewhere.

I will also o-ring the head and look into what is involved in dry decking the head. I dont think it will be hard as the oil gallery at the moment just travels up one of the studs.

I have already up graded the stock head studs from M8 to M10 wasted stud. I hope that will help with the things stretching.

[speedpro]

I've got access to some beryllium copper here so I am tempted to machine some valve guides and valve seats in a hope of controlling valve temps

That is nasty shit if my training in the Air Force is correct. OK as a complete tool or object but dangerous to work. Highly carcinogenic or something. Take care working it. I had a special toolkit for working around particularly strong magnets. If a tool was to break we were told very forcefully to vacate the area.

[Grumph]

That is nasty shit if my training in the Air Force is correct. OK as a complete tool or object but dangerous to work. Highly carcinogenic or something. Take care working it. I had a special toolkit for working around particularly strong magnets. If a tool was to break we were told very forcefully to vacate the area.

i agree .....Admiralty bronze is much safer and thermally very good. Personally, I'd only do guides as disturbing the OE seats could potentially cause more probs than it would solve....

The big overlaps I like are very unfashionable now. Historically, the best example was the Alfa Romeo 159 - post war GP car. Two stage blown 1.5 litre straight eight. 350 plus HP on Meth. So much overlap they referred to it as the extra stroke - or cooling stroke....
But it kept it reliable for 3 hour plus GP's with the materials available.
As an aside I remember reading a Don Garlits interview. Towards the end of his career and he'd just moved to the Donovan Hemi setup. He was hogging out ports and asking for more and more cam - including overlap - and was going faster and faster. He'd gone in the opposite direction to the popular Donovan setup - small ports, short cam - and was making way more power than the other Donovan users.

[Sketchy_Racer]

That is nasty shit if my training in the Air Force is correct. OK as a complete tool or object but dangerous to work. Highly carcinogenic or something. Take care working it. I had a special toolkit for working around particularly strong magnets. If a tool was to break we were told very forcefully to vacate the area.

I've had the fun of working with it for many years now, I make optic inserts out of the material for a living. It's not the danger beast that is perceived, you do need to be careful around the dust particles so it is important to always machine it wet, never dry.

I'll see if I can find some photos of the stuff I make. It's an amazing material so many awesome properties!

[speedpro]

and now it is . . . . . . .

[Pumba]

There was a video on FB a couple of days ago with it running.

[Sketchy_Racer]

Yeah been back in the shed tinkering with the supercharger bucket again. Slightly different configuration to what I was running earlier but seems promising.

Now running a AMR300 roots blower with a draw through system rather than EFI. Got a really basic cdi on there at the moment for ignition but plan on going ignitech in the future.

https://www.facebook.com/video.php?v=10152656211268757&pnref=story for video

[Grumph]

So as i said about 30 pages back, one step sideways, one step back, half a step forward....normal progress on a blower installation.

Bigger blower running slower and a basic draw through layout...At least it may see a track in that configuration. Make that work with usable boost levels then refine it...

So far, you and a lot of others have learned a lot from this. Your machining and fabrication skills have been developed. It doesn't seem to have cost you a lot of dosh either...Carry on.

[TerraRoot]

can't view your FB vid, upload to youtube?

[jasonu]

can't view your FB vid, upload to youtube?

+1 to dat sista.

[Sketchy_Racer]

So as i said about 30 pages back, one step sideways, one step back, half a step forward....normal progress on a blower installation.

Bigger blower running slower and a basic draw through layout...At least it may see a track in that configuration. Make that work with usable boost levels then refine it...

So far, you and a lot of others have learned a lot from this. Your machining and fabrication skills have been developed. It doesn't seem to have cost you a lot of dosh either...Carry on.

Yeah it's certainly having an open minded development!! Either way me and Kyle are having heaps of fun mucking around and as you say learning heaps which is just as much fun!

[Sketchy_Racer]

https://www.youtube.com/watch?v=P7XiYLOj_Ig&feature=youtu.be


So here's the video that was on facebook. This was the very first fire up with the new config, so jetting is a mile out on WOT but runs really well all things considered. Very responsive to throttle!

And we would have even done a power run if some numpty (me) hadn't left the clutch bolt loose thus rooting the basket. Oh well new one is here and only cost $40!

Hope to have the first power runs happening this week if all goes well. Just need to find some E85 somewhere aye ;)

[TZ350]

I love the flames from the exhaust, and it sounds hungary, good work, I am looking forward to seeing it out on the track. LOL hopefully you can get a rule change for the 85 as I would love to use it myself.... :D ... no wait I am actually doing something better.

[Flettner]

Like I said, "back in the day", 100cc fourstroke was unlimited including fuel. Should go back to that rule.

[Grumph]

Like I said, "back in the day", 100cc fourstroke was unlimited including fuel. Should go back to that rule.

I agree completely. i walked out of the MNZ conference when alky was banned except for BEARS and Classics. I'd been involved with the top F1 bike in the 2 previous years - running alky blends. Banned because we were too successful. Nitro needed banning, yes - but they threw everything out at the same time. crap.

[speedpro]

I've had many conversations with MNZ people a long time ago about the alcohol ban. I never could get a logical reason why it was banned. A lot of knee jerking about a particular event which probably would have happened if petrol had been in use.

How many people on this forum have seized an engine on petrol? Not like methanol is unique in that regard. In fact it is likely less of a problem as you can run it rich with only minimal reduction in power so there is no major benefit running it on the edge.

I had no personal agenda getting the rules changed as my bike was permitted methanol in it's class. It was just an idiotic rule in my personal opinion.

[TZ350]

As Buckets is a technical development class I would love to see fuel completely open, with anything goes ..... then we really could have some fun, I expect most projects would be self eliminating but exciting while they lasted :laugh:

[diesel pig]

Ha! That was the set up I was going to use for the one I was garnering parts for, good to know it works! Good on you!

[Flettner]

Ha! That was the set up I was going to use for the one I was garnering parts for, good to know it works! Good on you!

Would work better as a twin cylinder, pistons rising and falling together, even inlet draw. ( tandem )
Singles need a plenium ( ? ) and with a draw through carb you get throttle lag ( slight but never the less there ). Single cylinder with no volume / plenium is hard on the supercharger drive and can set up airflow resinance that will cause flat spots in the torque curve.
With valve port throttle / injection you will need a blow off valve as the pump is pumping all the time.
A twin cylinder neatly fixes all these issues.
Just had to add my bit.

[Sketchy_Racer]

Ha! That was the set up I was going to use for the one I was garnering parts for, good to know it works! Good on you!

Well now you know it works, you should chuck it all together and there'll be two supercharged buckets on the go! :D


Would work better as a twin cylinder, pistons rising and falling together, even inlet draw. ( tandem )
Singles need a plenium ( ? ) and with a draw through carb you get throttle lag ( slight but never the less there ). Single cylinder with no volume / plenium is hard on the supercharger drive and can set up airflow resinance that will cause flat spots in the torque curve.
With valve port throttle / injection you will need a blow off valve as the pump is pumping all the time.
A twin cylinder neatly fixes all these issues.
Just had to add my bit.

Need to find a CB125T and sleeve it down. Only problem is that the weight starts going through the roof!!! The only positive of the little chinese engine is that it is light. Although that may become a bad thing soon!!

[TZ350]

Need to find a CB125T and sleeve it down.

Funny you should mention that, Team ESE has an old CB125T Bucket out in the shed and a FZR Bucket chassis to put it in ..... hmmmmm supercharged 2T would be better but....

[Flettner]

may I ask, where did you get the little supercharger from?

[husaberg]

Would work better as a twin cylinder, pistons rising and falling together, even inlet draw. ( tandem )
Singles need a plenium ( ? ) and with a draw through carb you get throttle lag ( slight but never the less there ). Single cylinder with no volume / plenium is hard on the supercharger drive and can set up airflow resinance that will cause flat spots in the torque curve.
With valve port throttle / injection you will need a blow off valve as the pump is pumping all the time.
A twin cylinder neatly fixes all these issues.
Just had to add my bit.

It doesn't have to be a tandem, a 360 twin?
I seen a pic the other day of the supercharged 1939 250 single Motoguzzi gp bike it had a Plenium that looked the size of 10 litre bucket.

Glenn if you do want to do a twin I have about 2 fzr250 engines here in bits if you can get them up to you can have them.

(can't find a decent pic but have a look at the blurry 1939 one)
306993
(later he scans a pic)
307001

[speedpro]

Need to find a CB125T and sleeve it down. Only problem is that the weight starts going through the roof!!! The only positive of the little chinese engine is that it is light. Although that may become a bad thing soon!!
Pretty sure the 125T is a 180deg twin so it has odd firing intervals, same as my FZR. Funnily enough the FZR isn't that heavy despite starting as a 250. It isn't close to a MB100 though.

The Chinese motor being light is a good thing. Your rubbish bin won't be too heavy to move when you sweep the bits up, boost and revs and all that.

[speedpro]

Maybe I should send my FZR to you and you could fit the AMR300. The turbo is not going t be as good, certainly on a kart track

[Drew]

Fuck all that shit. 10kg No2 bottle ought to last a day on something as small as 100cc.

Wish it was allowed, 2 stroke with direct injected nos would be fucken awesome. Though, you'd need a garden hose straight from the fuel tank into the cases to stop it from leaning out.

[Sketchy_Racer]

may I ask, where did you get the little supercharger from?

I got it from here

http://www.kemotorsport.com/

I got the AMR300 but I would be interested in getting a smaller smog pump and trying them too.


It doesn't have to be a tandem, a 360 twin?
I seen a pic the other day of the supercharged 1939 250 single Motoguzzi gp bike it had a Plenium that looked the size of 10 litre bucket.

Glenn if you do want to do a twin I have about 2 fzr250 engines here in bits if you can get them up to you can have them.

(can't find a decent pic but have a look at the blurry 1939 one)
306993
(later he scans a pic)
307001

Thanks for the offer husa, but I'm going to tackle the single first. I don't think supercharging the single is going to be too hard. Probably a lot easier than turbo charging!!


Maybe I should send my FZR to you and you could fit the AMR300. The turbo is not going t be as good, certainly on a kart track

No no, we can't have that. You have me all excited about having a turbo charged bucket out there now!

[speedpro]

I have a reconditioned smog pump off some sort of big block yank engine. You can have it. Very interesting inside, rotary vane type of pump. They aren't really designed to provide any pressure so evidently too much over 5psi is pushing it.
I'm planning to go to Wanganui on Boxing Day and possibly to Wgtn in the days after so could bring it down.

[Sketchy_Racer]

I have a reconditioned smog pump off some sort of big block yank engine. You can have it. Very interesting inside, rotary vane type of pump. They aren't really designed to provide any pressure so evidently too much over 5psi is pushing it.
I'm planning to go to Wanganui on Boxing Day and possibly to Wgtn in the days after so could bring it down.

Sounds interesting! I'm going to be at wangas so hopefully we can catch up there otherwise if you are coming to wellington you will literally drive past my door step if you would like to pop in?

[speedpro]

After making my generous offer I thought I should go and see if I can find it. It's probably in cupboards with bikes leaning on them. I'll check tomorrow.
No solid plans about going to Wellington, just looking at a day trip to Picton whenever we get there and if we can get on the ferry. Pretty definite about Wanganui.

[Flettner]

I got it from here

http://www.kemotorsport.com/

I got the AMR300 but I would be interested in getting a smaller smog pump and trying them too.





Thak you, they look well priced.

[husaberg]

Just seen this...........
http://s-charger.com/50cc-supercharger/

https://www.youtube.com/watch?v=NOpIDsM1_P4
They are developing a 125cc version.

[Grumph]

The trouble with small blowers is that the loss of efficiency from clearance issues is multiplied due to the small size. if i was doing a blown 100, I'd be looking for a blower at least 250cc displacement and probably bigger. Run it slow and it stays cooler.
The only other viable alternative IMO is a geared up, belt driven centrifugal blower - probably the pressure side of a decent sized turbo. It wouldn't be any peakier than some 2 strokes. But bear in mind it needs to be pretty big - around 150mm dia impeller i'd reckon.

Husa - if you're bound and determined to give the FZR250 stuff away, give it to Muzza when he comes over for the pre 82 cup...I can do something with it.

[husaberg]

the AMR300 is pretty ideal for 1/2 end=gine speed and petrol granted
Re the engine did Santa not get any engines for Xmas..........
https://aboutlife2.files.wordpress.com/2013/12/naughty-santa-15.jpg

I just read the rest of your post I think a screw compressor would be the way to go an a small engine, likely suitable sized available ones from air conditioners.

[F5 Dave]

. . .
The only other viable alternative IMO is a geared up, belt driven centrifugal blower - probably the pressure side of a decent sized turbo. It wouldn't be any peakier than some 2 strokes. . . just careful where you are going with that Greg

[Grumph]

just careful where you are going with that Greg

I'm not claiming it would be any more reliable either....You'd have loved Mike Sinclair's T20 - I rode it back in the day - 800 RPM power band...

The prime example of how a centrifugal blower delivery works was the V16 BRM. All the drivers said you couldn't drift it as you'd start the drift at the bottom of the powerband and it'd build boost so quickly you couldn't hold it...round you went. When the thing was out here i saw it run at Wigram - it pulled wheelies out of the hairpin !!

Husa, i'm sure you've been saving that pic for the right moment. It's passed.

[Sketchy_Racer]

Well, I have a new clutch again and this time I made sure that it is tight! Hoping to get in the shed today and get some power runs with a bit of luck.

We had it running yesterday and I managed to get it to do a intake backfire, the pop off valve worked a treat and released all the pressure (and flames!) then sealed straight back up so really happy with that.

As for the supercharger, the AMR300 is running at a 2:1 under drive from the motor and seems really happy at that. Probably going to have to under drive it even more as the boost is up over 20psi and I really only want to start at 15psi so a new pulley may be in order.

[Sketchy_Racer]

https://www.youtube.com/watch?v=gZqcpPkuSWU&feature=youtu.be

Ok so too much boost. Going to have to make a new lower pulley. I found these guys over in Oz who have a supercharged XR100 which looks promising. They are getting 27.5hp out of there motor in the same configuration as what I am running at the moment. I need to spend a bit of time now and get the ignition timing right and look into the cam timing also.

At the moment with the blower running at half engine speed the intake air temp is far too hot (100+ Deg) so im hoping that when the boost is dropped down it'll improve a lot!

Also running at those revs the supercharger gear box gets very hot, I might have to investigate because it is nothing but two spur gears timed together so not sure why it's so hot.

And finally the carb that I have is rooted so i'm going to get a new one and a jet kit.

So far it's looking promising though. Even with this terrible setup at the moment we're close to double the original HP of the motor (which is not impressive at all) but just need to get everything dialed in and it'll sing!

[Flettner]

Can you thin the supercharger down to get the desired volume. I once thined a Wade supercharger to 30mm wide for one of my original Honda 100's.

[Grumph]

Can you thin the supercharger down to get the desired volume. I once thined a Wade supercharger to 30mm wide for one of my original Hoda 100's.

Ah, the good old diesel wade with alloy shafts. gave my last one away. Better to use a big blower run slowly, even if it seems like it's blowing mixture up in big chunks. never seems to make a significant difference to carburation or the way the thing responds.

[husaberg]

Ah, the good old diesel wade with alloy shafts. gave my last one away. Better to use a big blower run slowly, even if it seems like it's blowing mixture up in big chunks. never seems to make a significant difference to carburation or the way the thing responds.

I found a couple of Wades the other day.

[Flettner]

Ah, the good old diesel wade with alloy shafts. gave my last one away. Better to use a big blower run slowly, even if it seems like it's blowing mixture up in big chunks. never seems to make a significant difference to carburation or the way the thing responds.

There must be some minimim speed where the supercharger bocomes inefficient?

[Sketchy_Racer]

There must be some minimim speed where the supercharger bocomes inefficient?

Yeah there is, you can see it in the boost curve fairly easy if you log MAP. A roots blower should be linear in it's boost development but the slip at low blower RPM causes quite a lot of lost boost under 3000 engine RPM, but thats not really a problem.

I'm recovering a heap of this by running the blower wet. Makes a big difference to the pumping efficiency it seems.

The blower is certainly more than happy running at the speeds I'm planning. After all the lads in Australia are running the same blower on a 100cc and are making 27.5hp so there's potential.

They've been kind enough to send me their cam profiles so I spent the arvo profiling the stock cam. Needless to say I need to do some work! I have significantly less duration, lift and overlap than them. I've come up with a idea to make a el-cheapo cam grinder using a follower so I'll CNC out a profile and regrind the stock one. I can take quite a bit off the base circle.

So also I've got the head off at the moment and so far everything is looking pretty good inside the motor. No detonation (even at 25+ psi and 100* + IAT!!) and the valves also look sweet after about 2 dozen dyno runs. The poor little motor is also pulling to 12k RPM and seems happy about it too! Better than I was expecting from the pit bike motor!!

[Ocean1]

There must be some minimim speed where the supercharger bocomes inefficient?

I've been looking for a graph, but I think it died with my last laptop...

Looks like this: 307419

But it really depends on the specific blower, some of the later designs are getting far better adiabatic efficiency than the old roots blowers we stuck on small block Chevs.

[Grumph]

The problem with most traditional roots blowers - like the Wade - is that just when they overcome the slippage at low rpm and start getting serious they start losing efficiency from churning losses and turbulence at the intakes and exhaust ports. The guy who did the development of the refined martin blower in ChCh used high speed video and smoke in bench tests, Even the biggest martin was only about 1800cc displacement so it was intended for high rpm use. He developed flow separator bars on both inlet and ex. Worked a treat, ours held same boost to 13000 plus blower rpm. Reached max boost about 3000 rpm and held rock steady as far as we ever went.

Cams - I don't know what the setup is in the motor you're using. If it's flat followers, no probs cutting into the base circle. If it's sohc or similar with curved followers, cutting in can give you fits trying to grind to a desired lobe separation when in the motor. All the cam guys in NZ now use the Eutectic rod as an overlay and it works very well indeed. machines well and very good wear characteristics. Not too expensive either.

Could you post the cam figures the aussies are using or maybe PM me if they're sensitive....

[husaberg]

The problem with most traditional roots blowers - like the Wade - is that just when they overcome the slippage at low rpm and start getting serious they start losing efficiency from churning losses and turbulence at the intakes and exhaust ports. The guy who did the development of the refined martin blower in ChCh used high speed video and smoke in bench tests, Even the biggest martin was only about 1800cc displacement so it was intended for high rpm use. He developed flow separator bars on both inlet and ex. Worked a treat, ours held same boost to 13000 plus blower rpm. Reached max boost about 3000 rpm and held rock steady as far as we ever went.

Cams - I don't know what the setup is in the motor you're using. If it's flat followers, no probs cutting into the base circle. If it's sohc or similar with curved followers, cutting in can give you fits trying to grind to a desired lobe separation when in the motor. All the cam guys in NZ now use the Eutectic rod as an overlay and it works very well indeed. machines well and very good wear characteristics. Not too expensive either.

Could you post the cam figures the aussies are using or maybe PM me if they're sensitive....

Honda "pitbike" like grinds.
http://www.x386.net/TTR/tech/cam2.html

[Sketchy_Racer]

They're really happy to share information so no problem posting.

In the attached file (xcell spreadsheed) You can see two different profiles. One is a stock CRF100 and the other is what they are running on the 27.5hp motor. They got to 21hp with the stock cams retarded 3deg.

I haven't got the file on me at the moment for my cams but to give an idea, measuring at 1mm lift my intake valve is opening at 0 deg TDC and closing 21deg ABDC. 0-21 intake and I can't remember what the exhaust is, but it is equally shit.

The motor is a SOHC with curved followers. I was curious about trying to get the lobe separation. Although I have seen a cool mod using two cams machined and modified to allow adjustment of intake and exhaust separately. Might be worth looking into.

[husaberg]

Manx Norton/ international ......11 holes shaft 12 holes cams. Well that's how I thought it worked but maybe not...........:scratch:
http://www.racingvincent.co.uk/14%20Norton%20Site/Manx-Norton-10.html
Had an idea the AJS 7R had veneir adj cams as well

[Grumph]

[QUOTE=Sketchy_Racer;

The motor is a SOHC with curved followers. I was curious about trying to get the lobe separation. Although I have seen a cool mod using two cams machined and modified to allow adjustment of intake and exhaust separately. Might be worth looking into.[/QUOTE]

As i suspected, sohc. The main problem with cutting into the base circle here is that you finish up with the follower attacking the cam at a different angle...which changes the lobe separation. For the sake of your hair and maintaining some semblance of correct follower/valve tip geometry, I'd do a build up on the cam lobes. If you can keep the same base circle, that's one variable removed.

If you can do a vernier cam, it's worth trying. Lobes can also be on a taper - adjustment becomes difficult but it is possible.

[speedpro]

He'll only need one lobe to be adjustable plus a slotted sprocket. That will allow any adjustments required, apart from lift and duration.

[Sketchy_Racer]

This is what I am thinking of doing.

307482

[mr bucketracer]

my mate with his nc30 just cut the cam in 2 , he run a snug bolt down the middle of the cams with a good ground finsh on the ends , worked fine , i would make a 1 piece cam when sorted as its small and piss easy to make

[Ocean1]

This is what I am thinking of doing.

Some friction hub designs are getting quite compact now: http://mdmetric.com/prod/rfn/PDF_W-300-2.pdf

Not sure if they'd be quite low profile enough to mount each cam lobe individually onto a parallel shaft, but maybe.

[Grumph]

This is what I am thinking of doing.

Yeah, that or as MrB suggests, just cut it...ask him if they've got a suitable profile. way easier than doing it yourself.

[Sketchy_Racer]

my mate with his nc30 just cut the cam in 2 , he run a snug bolt down the middle of the cams with a good ground finsh on the ends , worked fine , i would make a 1 piece cam when sorted as its small and piss easy to make

Did he just use the friction between the two clamped halves of the cams to stop them slipping? Sounds nice and simple, I like simple!

[Sketchy_Racer]

Attached is my current cam profile in relation to a stock CRF100. I'm thinking of going the whole hog and setting it up as per the aussies 27.5hp cam.

[F5 Dave]

Don't be silly. Discretion is the better part of valour.

Take their specs and add a mm. Can't have the Aussies showing us up.

[Flettner]

Speedpro, have you got the other half of your Yamaha FZR head? is it useable, I've got a supercharger on the way!
I think I had a spare FZR head down at the storage cowshed, birds might have turned it back to boxite.

[speedpro]

I think I have a complete late model head. Will check tomorrow.

[Sketchy_Racer]

Speedpro, have you got the other half of your Yamaha FZR head? is it useable, I've got a supercharger on the way!
I think I had a spare FZR head down at the storage cowshed, birds might have turned it back to boxite.

Damn, I was wondering how long it would take until you would start a boosted bike and make me look silly :sweatdrop ;)

Did you get one through the Ozzy guys?

[Sketchy_Racer]

So hunting around trademe has been unsuccessful in finding a suitable carb. I'm after a 30mm+ CV carb if anyone has one or knows where I can get one. Needs to be in good condition preferably. The one I am using at the moment sat outside for a few years by the looks and just doesn't want to know about it.

[Grumph]

Use a car carb. Small SU or even a single choke downdraft Weber or Dellorto. There are very few aftermarket needle options available for bike CV's whereas the car carbs are pretty well infinitely adjustable.

[speights_bud]

So hunting around trademe has been unsuccessful in finding a suitable carb. I'm after a 30mm+ CV carb if anyone has one or knows where I can get one. Needs to be in good condition preferably. The one I am using at the moment sat outside for a few years by the looks and just doesn't want to know about it.
Might have something, cv carb off an xt250/225

[husaberg]

So hunting around trademe has been unsuccessful in finding a suitable carb. I'm after a 30mm+ CV carb if anyone has one or knows where I can get one. Needs to be in good condition preferably. The one I am using at the moment sat outside for a few years by the looks and just doesn't want to know about it.

Hey Glen might pay to undersize the carb 26mm would likely be ample, otherwise you will lose some velocity enriching effect. I am no expert but I have read it a few times...
scooter carbs are around that size....

[Flettner]

Damn, I was wondering how long it would take until you would start a boosted bike and make me look silly :sweatdrop ;)

Did you get one through the Ozzy guys?

Thank you Sketchy, you have inspired me to get stuck in ( well collect parts anyway ) and have another go. I feel I have some unfinished business. You know what it's like, not like I haven't got enough projects.
Nah, got one through "some guy" down south.

[Sketchy_Racer]

Hey Glen might pay to undersize the carb 26mm would likely be ample, otherwise you will lose some velocity enriching effect. I am no expert but I have read it a few times...
scooter carbs are around that size....

Hmmm this is quite a good point. As the flow through the carb at the supercharger entry will be constant (or close to it) whereas in a normal configuration it would be getting a big pulse every 4th stroke.


Thank you Sketchy, you have inspired me to get stuck in ( well collect parts anyway ) and have another go. I feel I have some unfinished business. You know what it's like, not like I haven't got enough projects.
Nah, got one through "some guy" down south.

Glad my mucking around was enough to spark the interest for ya. Looking forward to seeing how you get on if your two stroke development work is anything to go by!

[speedpro]

Found the smog pump, photos attached. Glen it's yours as long as you use it. I also have a scooter carb somewhere off my Yam 125, CV type & electric choke. Will dig it out and check size.

[mr bucketracer]

Found the smog pump, photos attached. Glen it's yours as long as you use it. I also have a scooter carb somewhere off my Yam 125, CV type & electric choke. Will dig it out and check size.if glen does not want it i will be very happy to take it off you (-::eek:

[Yow Ling]

Hey Glen, I have a set of cv's from a 550 they 26 or 28s, yours for the price of the courier about $10. good condition

[Pumba]

if glen does not want it i will be very happy to take it off you (-::eek:

I am looking forward to the hoarders show that they do about you.

[mr bucketracer]

I am looking forward to the hoarders show that they do about you.i'm trying no to be my old man but will happen soon bugger it , always wanted to super charge a bike , i have a wade superchager but think to big to make it work

[F5 Dave]

Fuck you would not believe the conversation me and Seymour had with Dave nthe ferry for the last BoB trip. Even I who would have a barn full was trying to convince him to sell some so he could finish the others.

[TerraRoot]

Found the smog pump, photos attached. Glen it's yours as long as you use it. I also have a scooter carb somewhere off my Yam 125, CV type & electric choke. Will dig it out and check size.

Speedpro, i believe that type of pump turns CW and need buggering about to rotate CCW (disclaimer: intertube copy and paste fact)

[Bert]

Fuck you would not believe the conversation me and Seymour had with Dave nthe ferry for the last BoB trip. Even I who would have a barn full was trying to convince him to sell some so he could finish the others.

Join the club Dave...
There is a couple of projects that I'd love to get my hands on. But alias NO... And they aren't even specials...

[F5 Dave]

Everyone else would wreck them. . .

[Flettner]

My little supercharger turned up today, nice unit. AMR 300.
Thank you Neil

[Flettner]

Found this stuff while looking for something else down at the storage cow shed. My old thinned down Wade, FZR head and the new AMR supercharger. The FZR head was destined to be the beginning of a 100cc twin fourstroke SC, might still happen?

[mr bucketracer]

Found this stuff while looking for something else down at the storage cow shed. My old thinned down Wade, FZR head and the new AMR supercharger. The FZR head was destined to be the beginning of a 100cc twin fourstroke SC, might still happen?good your going to play with a real engine (-;

[Flettner]

How can you call this a real engine, x2 = 100cc. Thank you Speedpro for the FZR parts.

[Yow Ling]

How can you call this a real engine, x2 = 100cc. Thank you Speedpro for the FZR parts.

is that FZR rod and piston? 125 then

I suppose if you destroke it it will be perfect

[Flettner]

is that FZR rod and piston? 125 then

New crankshaft, back to 104cc? What's the limit on SC 100 fourstroke?

[Flettner]

What would be a good frame to put the engine in? I'm talking cost effective ( cheap ).

[Yow Ling]

What would be a good frame to put the engine in? I'm talking cost effective ( cheap ).

3ln FZR250 would be easy and cheap, good size rims for slicks, room to lighten it, big enough for old men to ride

[Yow Ling]

New crankshaft, back to 104cc? What's the limit on SC 100 fourstroke?

the rules are not clear on this
The maximum capacity for rebored engines shall be:
F4 2 stroke 55-100cc - 104cc
2 stroke 55-125cc air cooled - 130.5cc
4 stroke 55-150cc – 158.09cc
F5 2 stroke 0-50cc - 53cc
4 stroke 0-100cc - 104cc

100cc SC is f4 not f5
If you applied the +2mm method for max overboring you may well get a bit of a lift as the pistons are so small

on a std stroke 124.84cc
on std stroke +2mm 135.48

[speights_bud]

158.09cc it is then... Hehe 😆

[husaberg]

New crankshaft, back to 104cc? What's the limit on SC 100 fourstroke?

if you could live with 180 degree why not weld and destroke it. Although I think 360 degrees would be better for forced induction. (Plus sounds better)
one of the models.The rods are definitely 2mm shorter or longer on one of the models with the pistons pin location different to suit.
They have different cam profiles too from memory.
I have a fair few bits and bobs for them too Neil if you want anything (guts of two complete engines)

[Grumph]

We've discussed welding and grinding on here previously. Someone - Speedpro ? - knew who had Summit Engineering's submerged arc machine. But you've still got to get it ground - and good, as in very small workpiece, grinders are now very thin on the ground in NZ.
Given Neil's access to CNC equipment I'd say less grief all round to simply make a new crank. I think the primary gear may be detatchable, simple enough to cut it out if it's not, and shrink/weld it onto a new crank.

[husaberg]

We've discussed welding and grinding on here previously. Someone - Speedpro ? - knew who had Summit Engineering's submerged arc machine. But you've still got to get it ground - and good, as in very small workpiece, grinders are now very thin on the ground in NZ.
Given Neil's access to CNC equipment I'd say less grief all round to simply make a new crank. I think the primary gear may be detatchable, simple enough to cut it out if it's not, and shrink/weld it onto a new crank.

Lot of time and material in a billet plus it would have to be ground afterwards anyway wouldn't it?
The CBR250 crank if cut in half would give a 360 crank I think it has larger journals to start with too. But I can remember (The CBR250 are 27 and 27.5mm big end jounrnals) they are 48.5mm x 33.8mm bore and stroke
the FZR250 crank primary drive is unlikely to be pressed on. See below.
Later bugger the FZR250 is 27mm journals I just went and measured
308727

This is the CBR250 crank
308728308729
cylinders 2 and three are closer and could form a nice 360 degree twin with the primary drive gear from the adjoining cylinder already in place.

[speedpro]

The rule book says: "24.2 Engines must be derived from non-competition motorcycles. Motocross, Road Racing, Enduro and Go Kart motors and transmission parts are not permitted. There shall be no restriction on the make, type or design of carburettor, ignition, exhaust, piston, cam, valve springs or cooling system except for class eligibility. All engines must be normally aspirated except F4 4 stroke engines of less than 100cc capacity, which may be turbo or supercharged. F4 2 stroke engines over 104cc are restricted to carburation equivalent to a single 24mm carburettor, F5 4 stroke engines over 53cc are restricted to carburetion equivalent to a single 20mm carburettor."

"less than 100cc" - that's it.

[speedpro]

In my engine I use the original cylinders 3&4. I think it would not be too difficult to go with cylinders 2&3 and leave the bit of crank with the primary gear and cut the rest off, except for the capacity of course.

To make it "doable" for average guys with average stuff in the garage it would be a whole lot easier if 125cc was allowed. Some of the capacity restrictions make stuff extremely difficult to achieve. The realities in nearly every case is that even with a couple of extra "cc" they still aren't going to set the world on fire but simply make it possible by reducing the cost and complexity of execution/manufacture.

[jasonu]

To make it "doable" for average guys with average stuff in the garage it would be a whole lot easier if 125cc was allowed. Some of the capacity restrictions make stuff extremely difficult to achieve. The realities in nearly every case is that even with a couple of extra "cc" they still aren't going to set the world on fire but simply make it possible by reducing the cost and complexity of execution/manufacture.

But if it was too easy everyone would be doing it.

[Flettner]

OK, 99.9cc it is then.
What I want is ( I think ) a 360 degree parrallel twin ( even induction ) with a balance shaft forward, output drive running off the end of the crank driving a standard clutch and gearbox. Horrizontal case split, short manifold from supercharger to cylinders, wet supercharger ie injection on the supercharger inlet. Gearbox will be home made version of the YZ250 ( home made so it's within the rules and robust) I would like to start fresh on the cases and crank so I don't have to compromise too much and make things a little stiffer ( crankcase and cylinder / head studs for example ) for heavy supercharge, as 40 plus HP is technically possible. Weight will be an issue ( not just mine ).
Sound like a fun project ???
I have my foundry nearly ready, can't wait to cast some parts.

[Bert]

OK, 99.9cc it is then.
What I want is ( I think ) a 360 degree parrallel twin ( even induction ) with a balance shaft forward, output drive running off the end of the crank driving a standard clutch and gearbox. Horrizontal case split, short manifold from supercharger to cylinders, wet supercharger ie injection on the supercharger inlet. Gearbox will be home made version of the YZ250 ( home made so it's within the rules and robust) I would like to start fresh on the cases and crank so I don't have to compromise too much and make things a little stiffer ( crankcase and cylinder / head studs for example ) for heavy supercharge, as 40 plus HP is technically possible. Weight will be an issue ( not just mine ).
Sound like a fun project ???
I have my foundry nearly ready, can't wait to cast some parts.

Sounds like a fun project.
Back the frame question, a tZR250 1KT would be ideal.
Lighter than a FZR, and not too bulky around the engine and good size wheels.

Engine casing redesign, I've always loved the aprilia SVX/RVX with the heads basically mounting directly onto the casing (sleeve consumed as part of the casing) piss poor job of explaining that... Here's a link


http://www.apriliaforum.com/forums/attachment.php?attachmentid=189563&d=1335461168

You could make some serious studs to deal with the supercharger...
With your skills I'm sure you could make it work for a parallel twin.
I can't visualise what the castings would look like.

[Yow Ling]

probably look like half of this, with a supercharger

308754

[Grumph]

Forget the balance shaft. KISS....and fercrissake it''s only a pair of 50's sharing a crank.
From vertical cylinders to 45 deg angle, use 70% balance factor. 45 to horizontal cylinders, use the reciprocal, ie 30% balance factor.
that'll be smooth enough to over 14 grand.

[Bert]

probably look like half of this, with a supercharger

308754

Bingo... Yes that would do it.