btr clutch question

[snoptel]

Hey everyone.

I'm thinking on building a board track racer and have been searching the net for ideas on different models..many ideas ar'brewen!!

Does anyone know what kind of the clutch system is used on the board track in the picture??

Thanks..

 

[Mr.B.]

Welcome to the forum!

That looks like it maybe the 2 speed transmission Indian motorcycles use in the early teens...

If so it has internal clutch plates much like what are found in automobiles, just smaller.

That would be a tough nut to replicate for most DIY’ers. You would need some serious machinery and the skills to use them.

Perhaps you do?

However, just recently a couple of members here have built jack shafts through the bottom bracket that look quite a bit like that.

Check out these threads...

http://motorbicycling.com/f38/sportsman-200-a-33611.html

http://motorbicycling.com/f36/merkel-board-track-copy-28747.html


-Kirk

 

[snoptel]

Hey, thanks a lot for the reply.

I have some skills, but lack some necessary equipment..

Anyway, my idea is to use an engine with internal gears and only have pedals to start the engine, so what I need is some kind of freewheel clutch system that will let me pedal.

A set up similar to the Indian's but without gears.

Hope someone knows what I'm talking about..

 

[Cycoracer8]

Sounds like a dry clutch setup is what you want. The smaller or light weight the gears in the tranny and the right ratio with dry clutch at the bump start the easier it will be to pedal through the tranny. Hope it helps, just my 2 cents.

 

[snoptel]

Sounds like a dry clutch setup is what you want. The smaller or light weight the gears in the tranny and the right ratio with dry clutch at the bump start the easier it will be to pedal through the tranny. Hope it helps, just my 2 cents.

Yes that's exactly what i need..now that you mention it

Thanks a lot to all that have helped.

 

[cobrafreak]

I know Indian used a one-way bearing as a method of starting the engine and releasing the pedals at one point. When they did this they had a two speed internal hub shifter in the rear hub.

 

[harry76]

I know Indian used a one-way bearing as a method of starting the engine and releasing the pedals at one point. When they did this they had a two speed internal hub shifter in the rear hub.

When is someone going to make a multispeed hub (thats built strong enough for our needs)?..... Or is there one available? I know you have the CVT which acts as gears, but for people that would like a more authentic look like Sportsmanpat's setup, it would be a very nice addition and come in very handy too.

 

[cobrafreak]

More authentic look? You have not seen the latest pics of my bike have you?

 

[harry76]

I seen the cover you made for the CVT, and although its a very neat setup it isnt quite as authentic looking then say Sportsmanpats setup with a multispeed hub.......... just sayin, i havent seen many boardtrackers with big belt driven secondary drives.

And of course by not running a CVT you keep the profile of the bike thinner, and the cranks dont need as much of a bend.

Im well aware of all the advantages of the CVT, i just think itd be nice to see a build with a Sportsmanpat or Goldy (Merkel build) setups but with a multispeed hub that would last. I think that would be sooooooo cool IMO

 

[cobrafreak]

You mean belt driven "primary drives". Nuvincey rear hub transmissions are CVT's and there are no planetary gears in it so it should last.

 

[harry76]

Yeah i meant primary..... i just looked at the Nuvinci hub, very cool. Has anyone used one of these with a larger sized MB? Im guessing you have to run a disc brake with it? Which i guess wouldnt be ideal if your plan was for authenticity........ im guessing you cant have one with a drum or coaster brake?

 

[cobrafreak]

Yeah i meant primary..... i just looked at the Nuvinci hub, very cool. Has anyone used one of these with a larger sized MB? Im guessing you have to run a disc brake with it? Which i guess wouldnt be ideal if your plan was for authenticity........ im guessing you cant have one with a drum or coaster brake?

Yes. There is no internal brake. You would need caliper, disk, or no rear brake.
You have to make consessions sometimes, even with an "authentic" build.
I chose to have two drums and a transmission. Some choose single speed. You can't have it all. If you did you may not like the performance or it may have safety issues. Using electric lights? That is not authentic. Self oiling engine? Not authentic either. What we are building our forefathers would have loved to run. Balance is everything.

 

[Cycoracer8]

I think snoptel was looking for a setup with gears & clutch that you could bump start the bike by pedaling. That's kinda what I have been looking for. The only thing I can figure is getting a separate tranny & clutch that is lever controlled. If I don't go with that, the CVT is a real nice setup & seems to be able to handle some hp. BTW can a bike with CVT be ridden & be pull started at the same time? I'd be talking about a Honda Clone pull start or a HiPerf Honda engine.

 

[cobrafreak]

Nothing with a centrifugal clutch can be bump started or pedal started unless you had a lock-in lock-out control. CVT's transmissions have Centrifugal clutches, so they can't. Bottom line is we need a manuel clutch rather than a Centrifugal clutch and we need either a ratcheting pedal sprocket mechanism or one with a one-way bearing. This is what you are looking for.

 

[snoptel]

I recently visited my local junk yard and found this "transmission" if it could be called that.

At first I thought it would be perfect for starting a engine by putting the engine in gear and pedaling until it started..but after I got home and took a closer look I realized that as it's pedaled the discs spin in opposite directions!!

Also, I can't can't seem to figure out what moped it's off of..

Has anyone ever seen something like this??

 

[Cycoracer8]

Hummm, the pulley looks like a variable clutch, or a variable pulley at least.Kool, if you can get it to work.

 

[Cycoracer8]

I've been thinking of cutting off a tranny/clutch from a 100 Yamaha or 125 Kawi. Not sure yet. The CVT may be just fine. Got more thinking to do.