Things you wish you done the first time.

Discussion in 'Frame Mounted Engines' started by bornagain, Nov 27, 2007.

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  1. bornagain

    bornagain Guest

    After finishing your frame mounted engines is there anything you wished you had done differently? One thing I will be redoing is mounting the engine again using rubber mounts so the vibrations are less.
    I'm hoping this thread may help new/exsisting builders of new motored bikes. ;)

  2. hot70cc

    hot70cc Guest

    using a rubber mounting gasket reduces the risk of frame brackage. I found out after i removed my engine how much the vibratiopn digs into your frame and i found that my frame was wearing thru so i mounted some rubber inside my mounts to save the frame to avoid breackage. a good tip.
  3. smitty

    smitty Guest

    I needed to put something under the frame mounts because my frame has a one inch down tube. Originally I used bits of inner tube, but the vibration wore through the inner tube, so I replaced it with some stiffish leather that was lying around the shop, and it has lasted longer than the rubber.
  4. bornagain

    bornagain Guest

    I'm planning to use rubber mounts from tree stakes, they look very durable. :)
  5. gottmoore

    gottmoore Guest

    I originally put my dax on a large tube cruiser with coaster brakes.

    Lessons learned-
    A coaster brake is not enough to stop a 250 lb rider doing 30. I ate up the brake, broke spokes and suffered constantly from wheel deflection, reulting in torn up tires from rubbing on the chain
    Rim brakes are the way to go as the whole spoke issue and deflection issues are gone.

    mounting issues
    I had a 1-1/4" tube to mount to, so I used a stainless steel mineralac strap (a common support for electrical conduit) and some dense rubber originally used for isolation of transformers.
    Great idea, but the motor rotated horribly on the frame resulting in poor alignment and gear box jams of the chain.
    go with a frame that fits the motor out of the box. Easier, better fit solid connection, and no slippage. Mostly this means an older frame, but hey
    you can still dress out in any fashion.

    Throttle assembly-

    the most dangerous part of the entire concept IMO. Does not fit standard handlebars, it hangs off the end giving a false sense of attachment to the bar. This need work!
    I traded it out for a stubby brake lever mounted like a thumb throttle. I feel way better and safer. I know you can also try a twist shifter by taking out the ratchet function and crimping an end for the carb, but whatever you do, get rid of the stocker throttle.

    Other tips
    constanly monitor torque of all bolts!!!!!!! I believe during break in, you need to wear a shirt that asks following traffic to honk if parts come off. :shock:
  6. Scottm

    Scottm Guest

    I was like a 5 year old at 5am Christmas Morning when the FedEx guy handed me my package. :shock:
    I would have taken more time, worked slower. Not used a pneumatic gun. I wish I had scrolled all the way down on Dax's web site to see the assembly pics of the carb slide.(Broke the cable) Most of all I wish i had known about MBc.
    My second bike, I took almost a week. Did a lot of sitting, looking, thinking and reading here. It really paid off inspite of the fact that I had already built one.:cool:

    Going slow in the build gets you going fast on the bike.
  7. The best advice I can give, .....

    Read every tip and thread on this website.

    I have (well most of them anyway) :p

    Its mde the task much easier

  8. JemmaUK

    JemmaUK Guest

    I think the best advice I can think of is take your time and build the machine as if the most precious thing in your world is going to be riding it...

    then check everything again... :D

    On my old bike I made lots of mistakes - more to the point I hurried and didnt really know what I was doing.

    On this one I was alot more careful and the tips on here were invaluable :)

    Jemma xx
  9. Danny3xd

    Danny3xd Member

    "Other tips
    constanly monitor torque of all bolts!!!!!!! I believe during break in, you need to wear a shirt that asks following traffic to honk if parts come off. "

    LOL Gottmore! 2 true.
  10. Jim H

    Jim H Guest

    I'm still finding parts; washers, nuts and various bike parts on the side of the road from my first build with the happy more happy time for me since the gebe rack mount and haven't lost the first nut yet.
  11. hot70cc

    hot70cc Guest

    needle bearings

    If I buy another engine that would be the absolute first thing i would replace (needle bearings). Even though the engine comes with them now, they are still not durable to a better quality one form a STIHL dealer, or another company. Second thing i would do is while the engine was stripped down, and carb. make sure there are no pieces of metal in the engine to destroy the piston or cylinder, use a sealent to reassemble the engine, also a sealent on the carb to avoid gas leakage. and replacing the air cleaner with a better filter so all that dirt don't get into the engine
  12. hot70cc

    hot70cc Guest

    Another thing i would suggest is to machine (taper) down the ports due to the rings takin little chunks out of them and destriying the cylinder.
  13. fetor56

    fetor56 Guest

    The one thing i should have done is bought a bigger engine.I bought the 48cc so if i was ever pulled over by the cops atleast it would be legal(legal as far as i could determine).....................mistake.
  14. dancycle

    dancycle Guest

    Make sure before you start the build that the bike you're using is solid and it's components are of decent quality. Also, the clutch should be the locking push button kind.
  15. jraice

    jraice Guest

    With the rubber mount debate what seems to be the current answer?

    I hear of people saying they used some sort of rubber mount, and then had scratches or frame damage..

    I also hear about problems with rubber mounts (although I dont know exactly what they are)...

    Is it best to just mount the motor solidly and see how the vibration is?

    Frame damage is a scary thought :/
  16. hot70cc

    hot70cc Guest

    solid mount, Yeah its the best for a secure mount, BUT.... try it for about 200 miles and then remove your engine and tell me what you think. So then I tried rubber, or you can use leather and the problem was solved no more diggin in. Its your call.
  17. Fly_boy_bc

    Fly_boy_bc Guest

    I take this to mean "File down or deburr the port where it enters the cylinder" Correct?

  18. hot70cc

    hot70cc Guest

    Correct, intake and exhaust ports, any little fragment or chunks and you loose power, as soon as the cylinder is nicked or gouged in any way , little by little you are going to loose power, you may not notice it at first but as time goes on you will. So to avoid the bigger chunks file down as much as you can, but not to much. BUT, as cheep as these cylinders are your always gonna have some pieces detach from the cylinder and scar the cylinder, and nick the piston.
  19. Fly_boy_bc

    Fly_boy_bc Guest

    Need Input!


    I would love to have all of this info Before I start the build. So far I have:

    Grease the gears in clutch unit, Put rubber sound dampeners in the cooling fins, drill or cut tube inside the muffler, put some sound dampening material in the muffler, and some on the engine coverplates.

    Now I have : deburr the ports.

    Anybody have anythig else?? Chain noise?

  20. fetor56

    fetor56 Guest

    For chain noise throw away your supplied chain tensioner and replace it with one that's spring that never needs adjustment or maintenance.
    Also replace your Chinese stretch-o-matic chain with a KMC 415H or better still KMC K910 Kool Chain(Extreme Freestyle).

    PS...forgot to mention:
    1.O-ring the carby(very important)
    2.Lights(if applicable)
    3.Stainless steel clutch cable wire insert.
    4.Seal the air filter.

    That's about it...good luck. :)
    Last edited by a moderator: Dec 25, 2007