Oddball engines and prototypes

[guyhockley]

Pity whoever did the photo captions doesn't know the difference between camshafts and crankshafts!

[husaberg]

Pity whoever did the photo captions doesn't know the difference between camshafts and crankshafts!

I fixed one could be bothered with the rest.

[ken seeber]

Hooser, brilliant articles by Millyard. Well done.
What a legend. Could only have been bettered if it was a 2 stroke...

[guyhockley]

Two videos that make an interesting pairing.
First, Mr Sweary from Yorkshire with a vintage tool:

https://youtu.be/E7TA4XogKtQ

Then a bloke from Asia for who that would be a bit high tech;

https://youtu.be/g6kZoxItnrQ

[husaberg]

Hooser, brilliant articles by Millyard. Well done.
What a legend. Could only have been bettered if it was a 2 stroke...

only 9 hours to make a 5 with basic handtools.

[ken seeber]

only 9 hours to make a 5 with basic handtools.

Again, he's a legend.

BTW Hooser, are you turning ?????

[husaberg]

Again, he's a legend.

BTW Hooser, are you turning ?????

Not to kawasakis and i swapped my two FZR250 engines to Grumph.
I did buy a GT380 engine the other day though.
I need another half of one to make a V4 crank though.
Interesting things those GT250 and GT380's
the cranks on both lend themselves to adding on extra cylinders
the GT250 ones have just a plain slip in pin joining canks (part13 in the pic)

the GT380s have a male and female fitting

To make single crank V4 out of a GT250 would require three cranks though.
What i like about them is they have 54mm strokes and std size pins 20mm and nice long rods 110mm which is unlike suzukis of that era
The center shaft on both is 25mm which means RD200 lab seals will fit and the other bearings are std size for rollers or balls 25x52mm ie KTM sized nu205
Neither appears indexed on splines ala rd250 like i would have thought.

maybe they have indexing pins like a Kawasaki?
i just need to convince Flet that building a V4 crankcase tp go with the Aprilia copy cylinders is a good idea

[guyhockley]

My brother-in-law is involved with a bloke importing classic bikes and spares from the USA to the UK. They've found some surprising differences between American and British bikes so no idea about NZ models, but;
There were several Sparton triple dnfs or drop offs in performance due to cranks twisting. I have an article about a Dutch owner who put Woodruff keys in his but then had further problems with "soft flywheels". Ian Read, the bloke with the RG250 barrelled GT380 seems to be running a bog stock crank, though...
Almost exactly 20 years ago I found a Barton top end so should have had first hand knowledge but sadly it wasn't to be.
Suzuki 250s have used various centre arrangements over here - some with 1 bearing and 2 oil-seals, some with 2 bearings and I'm pretty sure I remember one with a male female join like a RD but not sure about splines. Maybe dig around some more on CMSNL?
Is Phil Steggeman(?), the bloke who built the Suzuki 350 triple still around for advice? Think I got that right.
Any one got any engine pictures of his bike? To

[husaberg]

My brother-in-law is involved with a bloke importing classic bikes and spares from the USA to the UK. They've found some surprising differences between American and British bikes so no idea about NZ models, but;
There were several Sparton triple dnfs or drop offs in performance due to cranks twisting. I have an article about a Dutch owner who put Woodruff keys in his but then had further problems with "soft flywheels". Ian Read, the bloke with the RG250 barrelled GT380 seems to be running a bog stock crank, though...
Almost exactly 20 years ago I found a Barton top end so should have had first hand knowledge but sadly it wasn't to be.
Suzuki 250s have used various centre arrangements over here - some with 1 bearing and 2 oil-seals, some with 2 bearings and I'm pretty sure I remember one with a male female join like a RD but not sure about splines. Maybe dig around some more on CMSNL?
Is Phil Steggeman(?), the bloke who built the Suzuki 350 triple still around for advice? Think I got that right.
Any one got any engine pictures of his bike? To

Yeah the one posted was K,L,m ie RAM AIR another i seen has a Yamaha like set up (not sure re splines)
here it is here this is called the A,b Model 76 77


the GT380 crank is a little narrower at 50mm accross the wheels vs 57mm for the GT250klm so the 250 would have more crankwheel to grip.
Some of the parts of the crankwheels go back to the T250 and T350.
The Sparton I feel would have been higher stressed as it had much bigger pistons as it was a 450+cc Triple.
Either way GP spec v4's have a crank life of 1000-2000 miles or about 12-24 hours at most.
TZ cranks are problematic with their bigger 32mm coupler as well, for other reasons as they crack the big end hole as their is too little metal to support it.E
ither way its pie in the sky stuff for me unless Flet was keen.

[Grumph]

There were two 350 triples built here. Jim Cashman built the C3 which was raced in the support class of the Marlboro Series. He cast his own piston port water cooled barrels. One of them featured on the Westoby bucket single I put up in the chassis thread ages ago.

The other I know less about. Built at Boyles in Wellington, I remember it as air cooled. It was in a Steve Roberts built TR250 frame with the usual Ceriani forks and brakes those had. Boyles were at the time the leading Suzuki tuners in NZ - and Keith Turner's TR500 used a Boyle engine to get runner up in the 500 World title. Geoff Perry nearly won Daytona with another Boyle engine.
I remember Dale Wylie riding it at a Hawkesbury meeting ( a country roads circuit ) and winning nearly everything.

Husa - Wallace is fighting his way through a batch of T250/T20 cranks at present.

[husaberg]

There were two 350 triples built here. Jim Cashman built the C3 which was raced in the support class of the Marlboro Series. He cast his own piston port water cooled barrels. One of them featured on the Westoby bucket single I put up in the chassis thread ages ago.

The other I know less about. Built at Boyles in Wellington, I remember it as air cooled. It was in a Steve Roberts built TR250 frame with the usual Ceriani forks and brakes those had. Boyles were at the time the leading Suzuki tuners in NZ - and Keith Turner's TR500 used a Boyle engine to get runner up in the 500 World title. Geoff Perry nearly won Daytona with another Boyle engine.
I remember Dale Wylie riding it at a Hawkesbury meeting ( a country roads circuit ) and winning nearly everything.

Husa - Wallace is fighting his way through a batch of T250/T20 cranks at present.

tell Wallace there is details of the RD crank conversion here
http://www.t20suzuki.com/racing.htm#TZcrank

[Muciek]

Btw, does anyone have that RD "e" crank and could measure the holes and their position on flywheel (radius of hole center and deegre specing)?

[Flettner]

Yeah the one posted was K,L,m ie RAM AIR another i seen has a Yamaha like set up (not sure re splines)
here it is here this is called the A,b Model 76 77


the GT380 crank is a little narrower at 50mm accross the wheels vs 57mm for the GT250klm so the 250 would have more crankwheel to grip.
Some of the parts of the crankwheels go back to the T250 and T350.
The Sparton I feel would have been higher stressed as it had much bigger pistons as it was a 450+cc Triple.
Either way GP spec v4's have a crank life of 1000-2000 miles or about 12-24 hours at most.
TZ cranks are problematic with their bigger 32mm coupler as well, for other reasons as they crack the big end hole as their is too little metal to support it.E
ither way its pie in the sky stuff for me unless Flet was keen.

intetesting, im having this dilemma at the moment. My twin cylinder gyro engine center shaft is a press fit into the opposing crank wheels. This center shaft is hardened and has an output gear machined into it. This gear is clocked up and every bearing/seal surface ground concentric. This arrangment has twisted in the past with this fit perhaps being a bit lite. Lock tig welding has been applied and there has been no issues since (its been doing circuits) but thats a rough arse way (read desperate) can't sell them like that!
Could spline it, but that would be expensive and slow as the splines would have to be all ground afterwards due to distortion in hardening. Could make the shaft out of high tensile (no hardening required) but then I need to somehow attach a 60R gear to this shaft, more grinding/ expensive!
So plain press fit is a good thing for speed and cost. Do I just need a heavier press fit, perhaps?

[husaberg]

intetesting, im having this dilemma at the moment. My twin cylinder gyro engine center shaft is a press fit into the opposing crank wheels. This center shaft is hardened and has an output gear machined into it. This gear is clocked up and every bearing/seal surface ground concentric. This arrangment has twisted in the past with this fit perhaps being a bit lite. Lock tig welding has been applied and there has been no issues since (its been doing circuits) but thats a rough arse way (read desperate) can't sell them like that!
Could spline it, but that would be expensive and slow as the splines would have to be all ground afterwards due to distortion in hardening. Could make the shaft out of high tensile (no hardening required) but then I need to somehow attach a 60R gear to this shaft, more grinding/ expensive!
So plain press fit is a good thing for speed and cost. Do I just need a heavier press fit, perhaps?

No idea are crankshafts in gyros meant to be rebuilt serviced or replaced?
personally a touch of weld can be ground off and is still rebuildable.
Suzuki with the RGV500 ran into problems with twisting when they went to big bang so the just increased the interference they then ended up fatiguing and cracking the wheels.
maybe see what press fit others similar engines use
As I mentioned Kawasaki added a dowel for the threes male and females

sorry I cant find a better pic

much searching later

[Grumph]

If it's the center shaft press fit twisting, then yes, I'd think you could go to a bit heavier press fit.

As a reference, an Ossa motocross crank of dread memory, had an 8 ton press on the bigends.....At least it didn't move.

Where's the twist load coming from ? Drive engagement a bit sudden ?
If all else fails, you could always scotch key it.