Old multi-cylinder bikes of the 50s to later on. Japanese, British, Euro, etc

[Flettner]

Yes, I would like to see that! and you seem to have the means, the enthusiasm, the contacts (with people with expertise here) and faith in the two stroke.
We are allowed much more latitude with the use of two strokes in this country, why not make use of it? - at the same time of course, making sure that the "two stroke pollution" problem is addressed! - How about the OEM and Bombardier's technological advances in this area.

Trouble is, the young people have been conditioned into following American trends, which means complicated, heavy and expensive four strokes, (some as we know, being very retro and agricultural, with about the same power output as an old V-Dub) - whatever.
With the majority of young people at the moment, it isn't cool to have a two stroke on the road and they are the potential customers!

I'm very interested in flying too and have dabbled in that a little in the past. I do like your tandem twin concept. - do you use a proprietary gearbox? - do they give any trouble with prop backlash?

BTW - who is Rob? - I thought it was you, - got to get to know who is who here I guess!

Yes we can clean the twostroke up a little without going to complicated DI. I have shown this to be possible with the YZ250 EFI project, 14 to 20% less fuel burn over a standard unit under the same conditions and I'm sure with a little more injection timming fine adjustment it could be even better.

Autoflight builds aviation gear reduction units ( gearboxes ) so I've made all the gearboxes on my aviation engines. I made a mistake on the tandem design. I had one piston up and one down with both cranks turning the same direction, resonable ballance but terrible tortional vibration problems. Still not a real problem accept I made the crank drive gears too small and the taper attachment wasn't up to the job. I should have changed the way the gears were attached to the crank and used bigger diameter gears. But as usual I just put it under the bench ( lucky under the bench has a lot of room ) and started on a parallel twin. Although no more crank / drive issues the parallel twin vibrated as I said earlier. For the gyro application the I think the parallel is the better engine ( with ballance shaft ) as the exhausts are easier to run and I think customers see it as more normal. A bit like a Rotax.

I keep an eye on that tandem with a view to make a road going twostroke bike and with the succsess of transfer port EFI leaves the intake very short ( no carburetor sticking out ),one of the problems with side rotary valve engines. I do like the sound and the " feel " of the rotary valve twostroke. The sliding rotary valve cover ( valve timming adjustment ) just makes it all the better. My F9 Kawasaki using this tec has a very wide torque curve, as seen on Rob's ( TZ350 ) dyno.

The real problem is time as I have more than one project on the go.

Young people ( fourstroke riders ) don't know what they are missing!

[F5 Dave]

Well strangely it's the 'mercans that have made modern 2stroke easy and almost affordable to the average bloke. There are now a heap of big bore banshee engine kits in RZs reframed into something decent about the place, though I only know of a few in NZ. . . And mine is the only registered one (sadly on hold). Search Trinity website or CP industries to see what is available. It is dirty and compromised, but requires less involved engineering.

[WilDun]

Autoflight builds aviation gear reduction units ( gearboxes ) so I've made all the gearboxes on my aviation engines. I made a mistake on the tandem design. I had one piston up and one down with both cranks turning the same direction, resonable ballance but terrible tortional vibration problems. Still not a real problem accept I made the crank drive gears too small and the taper attachment wasn't up to the job. I should have changed the way the gears were attached to the crank and used bigger diameter gears.


Young people ( fourstroke riders ) don't know what they are missing!

FLETTNER.
Yes, young people don't know, full stop! - they don't care how it works they just go with the flow.
If it looks pretty, sounds like the current noise is supposed to be and consequently has sex appeal, then that's what they want (and buy), never mind the cost! - a bit like paying for bottled water!

Hope you get the tandem sorted out with counter rotation - it's got possibilites I reckon!

DAVE,
If those big American companies see fit to spend money on development work and productoon of two strokes then you can bet that the two stroke hasn't disappeared forever! They just have to fight to bring back the younger people whose minds have been poisoned by the anti two stroke brigade!

Cheers.

Will

[husaberg]

Just add a gearbox, 700cc twin, tilt the cylinders forward say 30 degrees and stuff the gearbox underneath. Also add EFI, vairable rotary valve and power valve. I'm sure a frame of some sort could be found for it. So who's up for one?
http://i1056.photobucket.com/albums/...w/db714673.jpg
http://i1056.photobucket.com/albums/...w/488ba783.jpg

http://i1056.photobucket.com/albums/...w/84283c8e.jpg

sure looks the shizzle... but how to go fitting in those huge exhausts for the 350cc cylinders would be the packaging issues
It would be a mental ride though........

[dangerous]

I keep an eye on that tandem with a view to make a road going twostroke bike and with the succsess of transfer port EFI leaves the intake very short ( no carburetor sticking out ),one of the problems with side rotary valve engines. I do like the sound and the " feel " of the rotary valve twostroke. The sliding rotary valve cover ( valve timming adjustment ) just makes it all the better. My F9 Kawasaki using this tec has a very wide torque curve, as seen on Rob's ( TZ350 ) dyno.

as a ex stroker racer that would be awesome, Id be in... with the know how you obviously have have you ever thought about a MVX250 type engine, or re working one so as it is relible?
I know a guy with a Vdue its not run in years and has thousands of faults on the ECU, again could you get one as a EFI sorted, and why would you use EFI over carbs anyway, try to clean the emisions up and ya put the engine at risk. a quality fuel and syn T2 is about as clean as a engine can run.

Does your engine use power valves?

[Kickaha]

and why would you use EFI over carbs anyway

Because FI is betterer

try to clean the emisions up and ya put the engine at risk. a quality fuel and syn T2 is about as clean as a engine can run.

Yeah right

[husaberg]

Because FI is betterer

Yeah right

When a two smoke is on the pipe it is quite clean... its just all the time it spends not on the pipe on the road that's the emissions problem.
On the whole all Bike engines are all dirty.......If don't believe me compare the fuel efficiency and and emissions for a modern 100hp bike and 100hp car.......

[koba]

FLETTNER.
Yes, young people don't know, full stop! - they don't care how it works they just go with the flow.
If it looks pretty, sounds like the current noise is supposed to be and consequently has sex appeal, then that's what they want (and buy), never mind the cost! - a bit like paying for bottled water!

Hope you get the tandem sorted out with counter rotation - it's got possibilites I reckon!

DAVE,
If those big American companies see fit to spend money on development work and production of two strokes then you can bet that the two stroke hasn't disappeared forever! They just have to fight to bring back the younger people whose minds have been poisoned by the anti two stroke brigade!

Cheers.

Will

Bah! Humbug!

I was lucky enough to have a few beers with Dave Croxford one day, it was at a planned but quite informal dinner (Beers) kind of thing.
He was talking about the start of his career and spending all of his money to 'tick up' the latest and greatest super-dooper off the shelf race bike at the time.

Sure he was a youth then but not 'the youth of today'. (Sorry Dave, if you ever read this I know you are young at heart!)

It think he said he borrowed quite a lot of coin from his Mum.

Conversely, I also know many a Youth, (Shit, Don't think I quite count any more) that is quite the opposite in the approach taken, more on the 'do-and-be-involved' side than the 'buy-and-go' approach.

Having said all that, younger people won't get into the mechanical side of the sport the same without the help of older heads heavy with experience; better to be fostering rather than adversarial.

[WilDun]

Bah! Humbug!

I was lucky enough to have a few beers with Dave Croxford one day,

Conversely, I also know many a Youth that is more on the 'do-and-be-involved' side than the 'buy-and-go' approach.

Having said all that, younger people won't get into the mechanical side of the sport the same without the help of older heads heavy with experience; better to be fostering rather than adversarial.

Dve Croxford - there's a name I haven't heard for quite some time!

I guess you are talking about the Bucket Racer types when you say 'do and be involved', and yes it is better to be fostering rather than adversarial.
We were all bucket racer types in my youth, - then there was very little of the window dressing and marketing ploys used to sell bikes, as there is today, - we just built our own "specials" if we wanted something different.
At least the bucket boys are interested in knowing every nut and bolt which to me is great!

I kept a couple of little motocrossers for my kids (teenagers then) and maintained them, but they were only interested in riding them, not maintaining or cleaning them! So I sold them, - bad move, I missed out on my bikes and they just went off and played football, enjoying themselves anyway!

Will.

[koba]

Dve Croxford - there's a name I haven't heard for quite some time!

I guess you are talking about the Bucket Racer types when you say 'do and be involved', and yes it is better to be fostering rather than adversarial.
We were all bucket racer types in my youth, - then there was very little of the window dressing and marketing ploys used to sell bikes, as there is today, - we just built our own "specials" if we wanted something different.
At least the bucket boys are interested in knowing every nut and bolt which to me is great!

I kept a couple of little motocrossers for my kids (teenagers then) and maintained them, but they were only interested in riding them, not maintaining or cleaning them! So I sold them, - bad move, I missed out on my bikes and they just went off and played football, enjoying themselves anyway!

Will.

This magnificent sport isn't for everyone!

[Yow Ling]

try to clean the emisions up and ya put the engine at risk. a quality fuel and syn T2 is about as clean as a engine can run.

What a load of bullshit

[F5 Dave]

. . .
I know a guy with a Vdue its not run in years and has thousands of faults on the ECU, . . .

Yup I've been dreaming of one of them.

Rip out the crappy Italian Morrini built cockup engine & replace with a YPVS big bore. Yum!

[Flettner]

as a ex stroker racer that would be awesome, Id be in... with the know how you obviously have have you ever thought about a MVX250 type engine, or re working one so as it is relible?
I know a guy with a Vdue its not run in years and has thousands of faults on the ECU, again could you get one as a EFI sorted, and why would you use EFI over carbs anyway, try to clean the emisions up and ya put the engine at risk. a quality fuel and syn T2 is about as clean as a engine can run.

Does your engine use power valves?

Wow, a real one? ( Vdue ), I wonder how hard it would be to fit an aftermarket ECU to it. Modern computers have come a long way since that engine. EFI has big advantages in stopping fuel escaping out the exhaust ( un burn't ). The key is the injection timing at the transfer port, almost what Bimota were trying to do.
Not having a carb on a side intake rotary valve is very desirable, makes for a much thinner engine and very short intake.

I think the YZ250 we have running on EFI says we have transfer port injection sorted in a twostroke. We haven't had a spanner or computer near it in, well, it would almost be years now.

[WilDun]

The key is the injection timing at the transfer port.
I think the YZ250 we have running on EFI says we have transfer port injection sorted in a twostroke.

I must admit rhat I'm a little hazy on the laws in America which seem to discriminate against the two stroke!

What are the reasons given by the American lawmakers for banning two strokes anyway?
Did they ban them just because they were two strokes or because they didn't measure up to their ideas on emission levels?

Did they assume that all two strokes are the same and put a blanket ban on them? or ban them just because they were crankcase charged two strokes (consequently having to use petrol/oil mix)?

Would they have banned them if they had used, say, poppet valves and blower charging, without the fuel/oil mix, even though they were two strokes?

Now that fuel injection has obviously sorted a lot of the problems that they (two strokes) were banned for, are the lawmakers likely to have a change of opinion or are they puppets to big four stroke manufacturers, as I have heard suggested?

OMC etc (I think I said OEM earlier! ) still persevere with two strokes so that is a good sign!

Will.

[Pumba]

...OMC etc...Will.

I am going to assume that you mean Bombardier? As OMC went bankrupt back in about 2000 and the Johnson and Evinrude brands were sold off to Bombardier.