Evolution of a motoredbike

Discussion in 'Photos & Bicycle Builds' started by Simon_A, Aug 17, 2008.

  1. Simon_A

    Simon_A Member

    Well my old MBc has been pulled down and has donated various parts to a new one.

    I originally bought a new Kmart bike which did its job well with the exception of the brakes, a wet winter and rim brakes didnt go too well. Also my HT got a metallic tick that I wasnt happy about so that made me take it off the road.

    With the release of the sick bike kit a new plan started to formulate itself in my mind. Build a new gasser. In the interim I built up a eBike on a bike I got cheap secondhand, this one had disk brakes.

    So the ideas started flowing through my mind and I decided to see what could be done, the disk brake frame had a much smaller triangle with which to fit everything but I wouldnt let that stop me.

    So I wasnt happy with the thought of my 48cc HT letting go so I ordered a new 66cc. At the same time I got the shift kit from sickbikes.

    Once all the parts had arrived I stripped all of the eBike parts off the disk brake bike and set them asside to be grafted onto the rim brake bike.

    I fitted the shift kit to the new motor and with the carb fitted there is no way it would fit. Hmm problem number 1. Much head scratching and I came up with cutting the bend off of the old inlet manifold of the 48cc and using that to offset the carby out of the frame.

    I wanted to use the old front mount off of the old MB but found the angles of the new frame were all wrong, problem number 2. So I designed a new angled mount.

    Then I found that the chainring on the BB and the output sprocket wouldnt get even close to lining up, Im talking 1/2 a inch offset. No idea why, but it was. So I decided to use BMX chain with its wider links to compensate for the offset. This worked well.

    Today with the bike not even finished was the day for its maiden test ride, much tweaking is still needed but it was at a point that I could do a test ride.

    Starting it is different, you do have to pedal the bike to start it, but I just rotated the right pedal up to 45 degrees and kick started the motor like a motorbike.

    Wow, changing gears is a buzz. The lowest gear on my cassette can start me off from a standstill and it wants to spin the rear wheel in the dirt with the slightest input of the throttle, and the highest gear saw me running at (without me realising it) 33.5 kph with a quarter turn of the throttle.

    Anyway the sick bike conversion was worth every cent. To have stump pulling bottom end and a decent top end with the motor not straining.......excellent.
    To get rid of the second chain and all of its associated woe's, and hardware....excellent.
    To run disk brakes front AND rear to pull me up in the wet and dry......excellent.
    I also did the LF clutch mod, so 1 finger pull of the clutch.....excellent.

    Basically once I have finished the bike, riding it will be.......excellent.

    Anyway the piccies show the bike as it is now, almost finished, the carby intake mod, and the clutch mod and BMX chain mod.

    Attached Files:

  2. Simon_A

    Simon_A Member

    Future mods will be fitting my halogen/led lights so I can see in the dark, thats why I have to rear rack for the battery bag.

    I also have my new carby, and an expansion chamber exhaust. The last 2 will be fitted once the motor is run in and running sweet.
  3. I'm itching to get that kit and get another HT on a bike with good brakes.


    Nice bike!
  4. stude13

    stude13 Active Member

    hey a; i would say you pulled it off. great execution.
  5. Simon_A

    Simon_A Member

    Well, its finished apart from the lights, I have a niggling problem with the LH plate of the sick kit, the layshaft keeps trying to move out of the bearing, there isnt any slack or movement in the assembly, its literally bending the plate, will reinforce it tomorrow.

    Apart from that I am satisfied with the bike now. I had a computer fan guard made by Marvel kicking around and decided to fit it as a piece to the clain guard, think it looks the part on this bike.

    Anyway what do people think?

    Attached Files:

  6. aussieboy

    aussieboy Member

    how much did postage cost for the sick bike parts shift kit cost to australia for you

  7. Simon_A

    Simon_A Member

  8. softride

    softride Member

    good on ya mate
  9. Alaskavan

    Alaskavan Guest

    The fan gaurd looks cool.
  10. Simon_A

    Simon_A Member

    Thanks Van
  11. cookcamp

    cookcamp New Member

    Simon great work mate, bike looks good. I have a rack mount 4 stroke fitted to my Hybrid, but just came into possession of a fairly light, large frame mountain bike, which I plan to build much the same as yours.
    I guess with the larger frame, should have more room, and the motor will sit lower. Did you buy your motor kit's from ebay?
    I'm thinking 48cc 2 stroke, with a sick gear kit, but I love 4 strokes, so might look at that option aswell. Anyway keep doing what your doing. Cheers Martin.
  12. graucho

    graucho Active Member

    This is my favorite part of this site. The modifications. You did a great job!
    I enjoyed your story of the progression. Ride on...
  13. BoltsMissing

    BoltsMissing Active Member

    Positive approach, Excelanto !
  14. Simon_A

    Simon_A Member

    Cooky, I got mine from Zbox. My last gasser bike had a larger frame with a 48cc, it was a lot easier to fit up, everything just fell into place. this one needed a bit more brain work but its well worth it.

    The plate flex issue has been resolved, and I fitted the light set to it, which was the last item on the "to do" list.

    The light set comprises a 3W Luxeon LED downlight as a headlight and a red LED downlight as a taillight. Both work extremely well.

    I will post a few more shots of the bike in the morning (its 21:20 ATM).

    I gave it a good run this afternoon and evening and everything was perfect, so I can say its finished till I have run the engine in.

    Then I can fit the upgraded carby and the expansion chamber exhaust.
  15. Simon_A

    Simon_A Member

    Thanks for the feedback and support everyone. I guess it came out good as this afternoon when I took it out I had someone shouting to me saying they wanted to buy it. But its for my enjoyment and not for sale :)

    Since its night time I just took a shot of the litghts in action. They work well as you can see.

    Attached Files:

    Last edited: Aug 23, 2008
  16. motoschwinn

    motoschwinn Guest

    really nice build!
  17. Mountainman

    Mountainman Active Member

    Clean looking nice MB

    looking at your pictures - gives me the urge for another MB

    yes - the addiction GROWS STRONG !!!

    Ride That Thing - Mountainman
  18. Makes me want the sick bike parts kit. it looks like it can really move!
  19. LocustsOfSteel

    LocustsOfSteel New Member

    So now that the engine has had some time to brake in... how fast will that jackshaft kit get you to in wot?

    I just need to know if i can ride at just over 40 mph without redlining before i decide to get one for my bike... i live in atlanta, and most of the cagers here are raging speeding kamikaze's, so i need to keep up in order to avoid being run off the road by some impatient suv driver.

    Thanks for any input :)
  20. Mountainman

    Mountainman Active Member

    fun rider also

    I think that is a good looking MB
    sounds like a fun rider also

    have a blast as you ride that THING