Adjustable Friction Drive - Need your opinion

Discussion in 'General Questions' started by CoconutFriction, Aug 19, 2008.

  1. CoconutFriction

    CoconutFriction New Member

    Hi, I built an adjustable rack that fits any bike from my 7 year olds, to my wifes and to my full size Trek Navigator. The goal is to offer various mounts on this rack. I currently have an 81cc 4-cycle, but am in the completion stages of a 49cc and an electic drive. All three engines/motors use the same rack and friction drive system. Since the pressure of the drive is fully adustable or even can be locked in above the tire, it works great. Even though the system uses a centrifugal clutch and can be used as a bike without effect, having it not touch the tire eliminates excess noise created by the clutch free spinning without the engine running. The rack system uses the saddle and rear axle quick connects for mounting so the whole thing can be removed in a few minutes. The engine uses a unique mounting frame that is easily adjustable in all directions for easy set up. Your thoughts would be great. By the way, this set up has been flawless, works incredible. Got a plate just in case.

    Attached Files:

    Last edited: Aug 19, 2008

  2. Happy Valley

    Happy Valley Active Member

    I'm intrigued by the set-up. I responded in the galley post.

    A close-up on the the roller assembly would be cool.

    Did you make the adjustable rack mount yourself?

    I notice what looks to be clam shell left side drive sprocket in one pic, what's up with that?
    Last edited: Aug 19, 2008
  3. JemmaUK

    JemmaUK Guest

    Now that is clever!

    I love the idea of having the roller wheel towards the back and under the rack so it can be easily adjusted on the bike.

    Curious about the 81cc engine - what sort of performance do you get out of it?

    it looks like fun to ride :)

    Have you found the NACC buzzing site yet?

    Jemma xx
  4. CoconutFriction

    CoconutFriction New Member

    Engine Performance

    The engine is great. I had a smaller sprocket on the friction drive wheel at first and it went like 50mph with bad low end tourque. I changed the sprocket and now it takes right off and cruises at 30 mph. The set up works great, couldn't be happier.
  5. s_beaudry

    s_beaudry Member

    Did you make the adjustable rack, or did you buy it somewhere?
  6. s_beaudry

    s_beaudry Member

    If you made that adjustable rack, you should be offering them for sale!
  7. CoconutFriction

    CoconutFriction New Member

    Yea, I make them. I designed it so I could sell them. I was frustrated with what I have ordered in the past, so off to the shop I went.
  8. s_beaudry

    s_beaudry Member

    Can I ask what you would sell one for? How long till you could build one?
  9. CoconutFriction

    CoconutFriction New Member

    I sell the racks for 69 or the whole system complete for 349, I have racks ready for paint, and a few engines in stock, so it would take just a few days to ship.
  10. Happy Valley

    Happy Valley Active Member

    Ok. If you're planning on selling them there will be questions.

    How does the system adjust on the fly?

    Do I need wrenches to disengage the roller?

    What's the kit weigh, with motor, as set-up in the pics?

    What's the roller assembly look like close up?
    Last edited: Aug 19, 2008
  11. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

  12. TWalker

    TWalker Guest

    ok, Im interested especially with that weird looking roller on the back. Not many detail pics of that but I understand you might not be ready to reveal it quite yet.

    I'm very curious though of what kinda traction that wheel is getting on the tire vs. a kneaded roller.

    But sweet! A center mounted friction drive! very interesting I could be a customer and I sell quite a few bikes.
  13. CoconutFriction

    CoconutFriction New Member

    Simple loosen the thumbscrews to adjust up and down, no tools needed. Then engine and rack weigh 30lbs, no wheelies. The center mounted engine keeps the center of gravity where it should be. The traction is great, I used a roller at first, this set up works better for me. I'm in the process of making a video so I can post it on youtube. I'll post some pics of the roller assembly as well. I have a web page, but I don't want to violate any rules for this website (I like this forum).
  14. CoconutFriction

    CoconutFriction New Member

    It adjusts with thumbscrews, no tools needed. You can raise it or lower it, disengagte it, etc, on the fly with no problem. It weighs about 30 lbs, since it is basically centered, your center of gravity doesn't really change, so it's not a hinderance when the engine is not in operation. I'll add some pics shortly.
  15. Esteban

    Esteban Active Member

    I love to see ingenuity ! I am not trying to be critical,, just asking ?? My questions are;, It doesn't look to be made of very sturdy materials. I wonder if it will last without bending, twisting with the larger, heavy engine. I would rather see/buy this set-up using a smaller engine such as a Subaru. Looks like too much weight hanging off the rear.