The Bucket Foundry

[Grumph]

That NSU system, how does it adjust for heat? As the engine heats up and expands so must the push / pull arms or will overload the bearings. Clearly I'm missing somthing?

Two eccentrics top and bottom coupled by links resembling con rods - phased at 90 degrees.
"the problem of overcoming differences in thermal expansion between the links and the cylinder is met by providing a member between the two shafts which maintains them at the same center-distance as the links, the variation in timing thus caused being negligible"

now you know as much as i do - and that was written by one of the best technical writers ever....

My brother had a Sport Max 250 NSU and i remember we looked at the setup, found it ran at more clearance in the "conrod" bores than it should but was silent and working well - so buttoned it up and left it alone....

I think Bentley used the same system in one of the big motors in the 20's.

[ken seeber]

[QUOTE=Frits Overmars;1130937466]Ken, why serve up a link that jumps to page 100 when the candy (Flettners linear crank mechanism) is on page 1? Don't you like us?

You're right Frits. I must have saved the GCAD as a favourite when on P100. Incredible range of mechanisms. Actually I have to thank Hoosa for getting me on to this in the early days of Ryger awareness when we were all trying to understand how it works. Probably still don't know, but it sounds like it won't be long.

Wonder though, whether the friction of the gears and pins is more or less than a normal crank & rod and the resultant piston side thrust. It certainly offers compactness PLUS the all important linear motion.

Grumph, you're right too re the NSU centre distance control link.

Don't you like us? What a question Frits? ESE and Foundry are some of the best things in years for me. Keeps us thinking, meeting new people, good people, honest, open, 2 strokes etc....great. Yep, I do like you all.

[WilDun]

Yowling has a neat goped engine... ,Maybe he will post the pic again.

I think from memory that Yow Ling's engine is the same as the one I have - it's the Italian designed two stroke Mini Motor (Mini Motore) but made under licence in England by Trojan and fits on the back of a bike. - capable of about 25 - 30 kph.
I'm told it was a competitor to the four stroke Ducati Cucciolo.

BTW All this stuff is just a fill in during a lull in Flettner's stuff - we haven't got entirely off track!

[husaberg]

I think from memory that Yow Ling's engine is the same as the one I have - it's the Italian designed two stroke Mini Motor (Mini Motore) but made under licence in England by Trojan and fits on the back of a bike. - capable of about 25 - 30 kph.
I'm told it was a competitor to the four stroke Ducati Cucciolo.

UPDATE - not entirely sure that the picture I posted was of a "mountain Goat" - will check it out.

Pretty sure they where originally called the farm bike and later the called mountain goat, my fathers frame was square tube (I think) but same basic design, although I think it had a swing arm and I can't recall it having the rear tow ball (but it has been years)

Here you go.

The full story.
http://pukeariki.com/Learning-Resear...-mountain-goat

http://tatatm.tripod.com/sitebuilder...g.w300h225.jpg

One of the members of my family has a duzgo
Same idea a cheap farm vehicle as there was nothing suitable available but destroyed by the same bureaucrats, only it was a car version.
it had two gearboxs mounted back to back for 13 forward gears with a supper super low of putting both into reverse, they had a 16 HP Kohler but most have a Honda V twin now.
They were made in the late 70's early 80's in one of most country towns of the West Coast Whataroa.
He made about 20 or so before he got shut down as they said he would have to comply with the new Vehicle rules, even though they were made out of recycled bits and bobs.
The wheels are motorbike as are the tyres with welded flat metal spokes.

Now Ken if you would whip down to Bunbury way and get a few photos of the double Chamberlin's in that ag museum down around there somewhere (it might have been Albany?)

[Frits Overmars]

I mentioned way back that someone suggested to Doug Hele the possibility of using the geared crank arrangement such as Flettner is probably about to use.

Can you dig up any more information on Doug Hele and linear motion cranks Will? I'd love to read about any issues without running into them myself.

This thread is going way off topic now!

As this happens with every thread I participate in, I wonder whose fault that could be...

That NSU system, how does it adjust for heat? As the engine heats up and expands so must the push / pull arms or will overload the bearings.

the dark push-pull rods drive the overhead camshaft http://www.nsu4.nl/english/e1ultrama...aftsystem.html
The light-coloured rod keeps the distance between crankshaft and camshaft under control.


EDIT: I see that Grumph beat me to it.

Wonder though, whether the friction of the gears and pins is more or less than a normal crank & rod and the resultant piston side thrust.

Gears are supposed to perform a rolling-only motion but friction caused by piston side thrust is far from negligible, especially with a short con rod like the Ryger's.
It's one of the reasons I love Flettners crank-within-crank system.

it had two gearboxes mounted back to back for 13 forward gears

4 x 3 (like in the first Kreidler GP racers) = 12
6 x 2 (like in the later Kreidler GP racers) = 12
How on earth can anyone arrive at 13?

[gsxr]

it had two gearboxes mounted back to back for 13 forward gears with a supper super low of putting both into reverse, they had a 16

Off topic on topic

Many years ago i had a beach buggy on aircraft tyres 1938 V8 side valve motor.
2 humber gearboxes reversed with a push button overdrive between them.
Gave an effective 20 forward and 5 reverse if requirded

[Grumph]

One of the members of my family has a duzgo
Same idea a cheap farm vehicle as there was nothing suitable available but destroyed by the same bureaucrats, only it was a car version.
it had two gearboxs mounted back to back for 13 forward gears with a supper super low of putting both into reverse, they had a 16 HP Kohler but most have a Honda V twin now.
They were made in the late 70's early 80's in one of most country towns of the West Coast Whataroa.
He made about 20 or so before he got shut down as they said he would have to comply with the new Vehicle rules, even though they were made out of recycled bits and bobs.
The wheels are motorbike as are the tyres with welded flat metal spokes.

One of the two brothers involved with this is Kevin Giles of KG Motorcycles in ChCh. He has a running Duzgo and most of the promo literature. Absolutely butt ugly things they are...
As for the 13 gears, can I suggest that as Whataroa was a sawmill town deep in feral Westland, they may well have run out of fingers and toes to count the gears on....

[F5 Dave]

And neutral isn't really a gear.

[WilDun]

Can you dig up any more information on Doug Hele and linear motion cranks Will? I'd love to read about any issues without running into them myself.
As this happens with every thread I participate in, I wonder whose fault that could be...

I'm sorry Frits, I did try to find that article about Doug Hele quite a few times but no joy. As I recall it was just in answer to a reporter's question asking about whether or not it would be feasible for production etc. and didn't go into any real detail. Probably from the 'Motorcycle', 'Motorcycling' or 'Motorcycle News' mags of the sixties.

Don't think there is any "fault" involved with us wandering off topic now and then, just so long as we realise that and always wander back again - if there is any of us at fault, then of course I would be involved! but the thread hums along quite well and even though we don't hear a lot from Yow Ling these days I guess he is happy enough with how it's going!

[tjbw]

...

Gears are supposed to perform a rolling-only motion but friction caused by piston side thrust is far from negligible, especially with a short con rod like the Ryger's.
It's one of the reasons I love Flettners crank-within-crank system.

...

To reduce the friction due to a 90mm rod, why not use a 110mm rod with a 20mm spacer between crankcase and cylinder/valve block?

[Flettner]

Mazda Rotary have a similar but different gear system in their rotor housings / side case to control the motion of the rotor. Those gears don't give trouble as I understand. Granted this crank within a crank system may be a little harder on the gear set.
Big advantage is the rod and bigend weigh (technical term) bugger all, no centrifugal loads on the big end or rod. Centrifugal load on a bigend bearing is far more damaging than combustion load, harder you rev the worse it gets.
A longer rod is just heavier.

[WilDun]

I think that maybe gears use forces something similar to rolling motion when idling, but when real force is applied (eg. when transmitting power) it is as much pure sliding motion (between teeth) as it is with piston side thrust, except that the forces are now concentrated on a very small area but are more easily lubricated by increased availability of pure oil. - then, there's the cost - high quality steel, hardened and ground gears (as these will need to be) don't come cheap!
Nobody seems at all sure what the result of this theoretical arrangement will be (I for one can't remember ever seeing it used before)

Sorry to sound like a 'dampener with a wet blanket' ...but everything needs to be considered! and if anyone is really going to find out, then no doubt it will be Flettner !

[Flettner]

I think that maybe gears use forces something similar to rolling motion when idling, but when real force is applied (eg. when transmitting power) it is as much pure sliding motion (between teeth) as it is with piston side thrust, except that the forces are now concentrated on a very small area but are more easily lubricated by increased availability of pure oil. - then, there's the cost - high quality steel, hardened and ground gears (as these will need to be) don't come cheap!
Nobody seems at all sure what the result of this theoretical arrangement will be (I for one can't remember ever seeing it used before)

Sorry to sound like a 'dampener with a wet blanket' ...but everything needs to be considered! and if anyone is really going to find out, then no doubt it will be Flettner !

No, well designed gears are rolling contact, heavy load still rolling contact unless the tooth deforms. So it just means that the gear needs to be robust enough not to deform a significant amount. Trouble is in this gear set there is not much room. I have made the gear set 15mm wide in an effort to reduce tooth deflection.
Who knows? I will just have to try and see. It's all there now although I would like to chage the crank flyweels to be bigger (balance reasons) and a better attchment system, at the moment it's a bugger to put together, as I said.

So if the rod is made from 7075 alloy what coating will be suitable to slide in the under piston bushing? Perhaps hard anodise against a carbon lined bushing? Minimal friction, hard chrome would be good but we can't do that in NZ (hard chrome on to alloy). Perhaps nikasil?

[Grumph]

So if the rod is made from 7075 alloy what coating will be suitable to slide in the under piston bushing? Perhaps hard anodise against a carbon lined bushing? Minimal friction, hard chrome would be good but we can't do that in NZ (hard chrome on to alloy). Perhaps nikasil?

What sort of temps are you expecting? I've used a Moly loaded nylon base bush for several applications. NZ made - Husa can probably find it.
From memory, permanent deflection around 250C and around 100kg if it's well supported. Got some here but can't find what data I had.

[Flettner]

Sooo, made some more adjustments to the HCCI engine, I'm still shaking, how do you stop a runaway compression ignition engine? stop the fuel, no, the crank case is full of fuel oil! Shut off the air? No the exhaust without a pipe on can suck air back in but it will slow the run away. In answer to you question Frits yes it DOES rev and it was only on twostroke OIL.
Thankfully it run out of oil before it exploded.