Kill the vibration

Discussion in 'Frame Mounted Engines' started by Bikeuser, Jun 26, 2008.

  1. Bikeuser

    Bikeuser Member

    I am having some motormounts designed for the HT engines. would you be willing to pay 50 dollars for substantially reduced vibration?

  2. bushido

    bushido Member

    yeah, i think it would be worth it, especially if they solve the issue of the engine bolts shearing out of the block.
  3. Marktur

    Marktur Member

    NO, way too expensive.
  4. Great idea, but I really don't have any vibration so far- at least that is uncomfortably noticeable. I have gone about 34mph on my bike now and can't really tell I have a motor on it. I posted my idea a while ago, and it got very little response. It's been nothing but successful for me since day one. And it cost me about $5.00 to make. The big fear was the stress on the back mount. So far I haven't noticed any breakage or stress fractures at all. I used rubber in all area's, and that seems to absorb most of the residual vibration.

    I would be curious to see what you come up with though.

    couple pic's of what I did:

    Since the pic, I added a neoprene washer on top of the bolt for any backlash from the spring.

    thanks for the heads up thinking!!

    Troy Fitz.

    Attached Files:

  5. darwin

    darwin Well-Known Member

    Carrot cool idea, no great idea. In the 1st pic your wires are right in the pinch point of the know better.
  6. "In the 1st pic your wires are right in the pinch point of the know better. "

    Your right I do, that was only a build pic. :grin:

    Here is a more complete build pic:

    All nice and tidy!


    Troy Fitz.

    Attached Files:

  7. pedalpower

    pedalpower Member

    I'll be looking into exhaust hangers from the local auto parts store to use as shims, bushings, mounts, etc.
  8. bushido

    bushido Member

    carrot! excellent thinking and ingenuity! please make a build thread about what parts you used and where you got them, i think your idea is the best solution i've seen so far in respect to mounting issues.
  9. ozzyu812

    ozzyu812 Member

    Nice! You got little response b4?:eek: I believe valve springs would work nicely.
    I was trying to thinking of some elaborate solution using the shock off my donor suspension bike frame.
  10. fatboy67

    fatboy67 Member

    I fabricated complete new mounts. Front AND rear that have 6mm rubber that insulate the mount from the frame, and I only got one response.
  11. fastboy9

    fastboy9 Member

    A spring is a good idea! I've got one on my front mount but its on the other side of the frame, just as a spring to stop the the vibrations vibrating the bolts off. And it makes so much of a difference!! That plus rubber shims too. I can easily ride for an extra 10 miles before the elbows start to vibrate apart.

    Also heres another idea, you know the rear mount is a block, one end on the engine, the other end to the frame, well what if you was to replace this block with a much more vibration dampening material? The advantages would be:

    1. Less frame fatigue, one guys seat post tube snapped once!
    2. The block isnt going to fracture, I have had this done before.
    3. More comfortable ride.
    4. Stops the vibrations from damaging all the other parts, including shaking nuts and bolts off.

    This is the best source of material I could think of. I dont know if you guys have ever seen it, but when I was a kid learning to swim at school, we used to dive to the bottom of the pool to pick up a big brick made out of thick rubber, they are called dive bricks. Well if you were to buy one of these, you could cut and "machine" it to fit, with your hands (saws, files maybe drill)! People speak of results from just putting bits of tyre in between their frame mounts, well if you was to replace the whole block with a much more durable absorbent rubber block then this would be perfect.

    Heres a link to what I mean if your not sure:

    Anybody think of any other material sources? As these bricks are quite pricey.

  12. bushido

    bushido Member

    some people use hockey pucks for engine mounts in cars, maybe that would be a good meaterial to dampen vibrations? or maybe its too solid?
  13. fastboy9

    fastboy9 Member

    good idea! The dive bricks are pretty solid too, but I guess you need a bit of rigidity if you are too replace the engine mounting block. If you got hit in the face it would break your nose and jaw maybe, so they are pretty solid!
  14. Marktur

    Marktur Member

    Troy - I'm interested in making a mount, or buying it from you (if reasonable). Can you list the parts or sell me one?

  15. adamtheha

    adamtheha Member

    Carrot...that's a brilliant idea, and I'm determined to go imitate it right now, if you don't mind : )
    Is that a valve spring? What size of bolt is through the frame? And, where did you get that little rubber piece on the bottom part?
    Thanks again for your idea.
  16. Marktur

    Marktur Member

    c'mon Troy - we're interested! :)
  17. motor puzzle

    motor puzzle Guest

    Nothing fancy

    I cut a strip from and old car tire and plan on sliding between the frame and the motor mount. My engine only vibrates when I reach about 15 MPH and stops when I accelerate to 17 mph.

    Attached Files:

  18. ozzyu812

    ozzyu812 Member

    Nix my valve spring idea. Upon further thought. They are too tight. It would be the same as block of steel.
  19. Bikeuser

    Bikeuser Member

    you guys are doing it all wrong. The rubber you are using is way to hard to reduce the vibration. kudos to the spring idea.
  20. motor puzzle

    motor puzzle Guest

    So Bikeuser, how about a suggestion?