While all this talk of CVT and clutches and such is kewl and enlightning. I gotta say I like shiftin gears. What would be a good set of ratios to look for? If I had lots a mony I'd buy a baker six speed. But if that was the case my progect would be beyond the design stage .
I know I want overdrive.
I'm thinking of taking a six speed out of a Dirt bike, making my own case and using that. I was thinking a close ratio one but I'm not sure they have overdrive.
I think making a case shouldn't be 2 hard make 2 sides that the shafts line up like the originals , use a solid shaft in place of the crank, then close the whole bugger in. May even be able to play with some gears while you're in there.
maybe this just sounds good in my weee little brain just thought i'd see what others thought.
Gumps,
You know your engines power band, you can figure out how many speeds it's going to take to get from dead stop to top speed....just a little calculator work. I don't believe in shifting anymore than necessary (IMHO). I've read about others using 3 speed boxes (Albion) on their bikes.
Cris
1980 GS850 converted to 10hp diesel clone power.
2006 Jetta TDI for road work.
2007 Bonneville
I like shiftin' gears too. But I kept playing around with trying to find a "workable" transmission/drive unit. And eventually decided going with the CVT.
Small suitable trans's are hard to come by here in the States. I pretty much exhausted all possbilities. Toyed a long time with the idea of whacking off a 2 stroke bike trans unit and rigging it up, but always went up against spacing problems. Also played with the idea of a centrifugal clutch/trans unit.. Just coulodn't seem to make it work the way I wanted.
Also look at riding mower trans's. Knew a guy who used to build trikes with them, but always ended up against the wall... In the end, went with CVT.. Guess I'll live with it. (least til I come up with another project.
Rickt now, it's a rolling chassis with all the mounts for the engine/cvt.jackshaft on it. I should have it "roughed in" by tonight.....
Rich,
Your go'in the right direction. Tonight I took my Kamazuki out for a spin, and appreciated the CVT's ability to get things right. While I sound like a complainer about the system, it does work, provided you do not overload the take off gearing, that is, keep your jackshaft/rear wheel sprocket ratio to where the CVT is not having to struggle to get things moving. I've geared my bike to run about 50 mph, and taking off is very smooth and none wearing to the drive unit (at least I hope so).
People get into trouble trying to go fast on diesel bikes. Gearing is always an issue as these engines do not have the wide power band found with using motocycle engines. While some of our engines may have the HP to get us fast down the road, we can't get the gearing to do the job.
Cris
1980 GS850 converted to 10hp diesel clone power.
2006 Jetta TDI for road work.
2007 Bonneville
I've also thought of a 2 speed ATV gear box from a mid 90's Polaris 4 ATV. Would at least give you High /Low and already set up for CVT. Won't be able to shift on the fly but maybe coud use low for around town and High for the Highway. Whatcha think?
Gumps,
A two speed box sounds nice, and it's probibly like a Cushman two speed...no
syncronizers. If you run a box like that, it only adds to the complexity of the drive train, and more HP loss.....just my $.02 worth.
Cris
1980 GS850 converted to 10hp diesel clone power.
2006 Jetta TDI for road work.
2007 Bonneville
I bought some Norton Atlas Gearboxes & other parts intending to use them on a diesel build. I don't think i'm going to use them now so i put them on Craigslist. If you're interested they can be viewed at https://accounts.craigslist.org/post/sh ... 4779&db=lv
How does the CVT hook up to the engine (whichever engine you choose)? Is the primary drive connected to a CVT transmission which is then connected to the rear wheel via chain/sprocket or belt/drive? Or is the CVT mounted on the drive shaft and connected directly to the rear wheel?
I've seen a couple examples of bikes using Harley based drive setups, i'e' primary/tranny/rear wheel. Of course there's power loss there I am sure.
CVT drive unit goes right on engine crankshaft, driven unit goes on layshaft (some of us call them "jackshaft's). From there, you have your final reduction ratio to rear wheel.
Cris
1980 GS850 converted to 10hp diesel clone power.
2006 Jetta TDI for road work.
2007 Bonneville
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just thought i'd see what others thought.
