So It begins another project as I wait for my carbs. I don't know if I should post this in here or if anyone cares but I thought I would document it for CCM or anyone else interested in making a bump starter for those serious race bikes with a total loss electrical system. Any way here is the beginning of it as I have all of the major parts and got the iron to make the frame, all I will need is the wheels.
212cc gas motor, 2 @ 1" bore pillow blocks, kart race slick and rim, 1" live keyed cart axel. 1" cart hub, 41 pitch chain, 5/8" drive sprockets, 1" final drive sprockets, collars, bicycle cable and brake lever for throttle.
The hub didnt fit the rim so I had a machinist buddy turn down the hub boss to fit the inside and drilled new holes for the hubs.
Motorcycle: 96 GSXR750, 07 CBR1KRR, ZX7/9RR F-USA AMA
Re: Bumpin rubber uglies
Yay, something for ME!
I never get anything, just for others.
Will follow this eagerly, although it may be awhile before I get to try it on the srad race bike, as i first have to drop the motor on the new bike and go through it.
Will test on the CBR1KRR.
Awaiting your carbs in trade sir...
Yes sir was hoping I wasn't going to have any major carb problems so I could test it out on my bike. Might be able to get a friend to bring his bike over to test it before I ship out to make sure there are no problems. This is gonna be pretty cool, I like figuring out how to make stuff.
So I laid out the final drive, hub and block locations, got a baseline in and out for the final drive shaft from the motor and most importantly got the center to center for the frame. Tomorrow I can start on the frame and motor plate and figure out a way to have the pillow blocks adjustable like a swingarm to adjust the chain tension and make a chain guard. This is gonna be a lot more work than I originally thought but I think its gonna turn out tits.
Why not go with a centrifugal clutch on the motor for safety's sake or is there an internal clutch on that motor?
You could also use a swing arm for the drive wheel that may allow for the adjustments you seek while also prefabbing a major part of this whole project?
To take it a step further...you could use the original swing arm pivot as a jack shaft if need be?
Because I'm $400 deep into this not counting any of my time and we are trading, I probably would have been better off just paying for the carb job. A centrifugal clutch is another $100, which can be added at a later time if he would like. Thats why I'm going to make a chain guard and test it before I send it out and the thing is only going to operate for maybe 20 sec a pop ?
motor shaft is 5/8" you are correct sir but I can't find the diameter of a a 5/8" clutch to drive off of the motor like it should be so the clutch would hit the motor mount plate the way I have it drawn up. Plus the motor maxes out at 3500 rpm and the clutch only engages at 2300 rpm. I guess I should ask Chris how far he wants to go with this. A clutch would be preferred though as you are saying.
I was thinking...
Take an unbraced swing arm, weld a plate on top for the motor, mount it on pillow blocks via the pivot shaft, use the stock adjusters to keep the chain tight, make a screw type adjuster to raise/lower the rear and affix it all to a platform for a low cost, fairly simple bump starter.
You can work out the details but that basic configuration just came to mind.
I'm also wondering if a chain saw motor, with it's internal clutch & compact design, would be the ideal power plant?
Ya that ship has already sailed, haha. The motor and all the pillow blocks and sprockets and stuff ain't cheap though. I was gonna try to go cheapo and just get a shaft coupling and 1 pillow block and just mount the tire right off the shaft with a pillow block right next to the shaft to take the wobble and load out of it but decided not to.