Engine Trouble 48cc, 66cc conversion

Discussion in '2-Stroke Engines' started by foshizzle01, Aug 29, 2013.

  1. foshizzle01

    foshizzle01 New Member

    So, i recently bought myself a huffy cranbrook, and a grubee skyhawk 48cc, and went to work and built my first motorized bike! The bike went together relatively smoothly, and works great! well, right now its running too rich, but the crap carb that came with it doesn't have any airl/fuel adjustments. (no screw, or extra c clip notches on the needle) Hopefully this will be able to be fixed when my nt carb comes in the mail. But anyways, i got the 48cc because a friend recommended that, and i trusted his opinion. he recommended that because the state laws require the engine to be under 50cc. But after reading that there is really no way for a cop to judge the size of the engine just by looking at it, i am now questioning my decision on getting the smaller engine. so what do u guys think? i understand that the build is being done to a beach cruiser, and these bikes can get a little sketchy after about 30mph, but it would be nice to have a bit more low end torque and hill climb power. is there any way to upgrade my engine to a 66cc without buying a whole new one? or would i get just as low end power from say an expansion chamber and high flow filter? (btw, i dont want to gear down because i still need the speed to get down the streets i mainly ride on)

  2. BigBlue

    BigBlue Active Member

    A 55cc or 60cc kit might help boost the performance for about $50.00 plus shipping. I've never done one, so I'd check with other members input before you pull the trigger.


    I don't think Mike Simpson is selling the 55cc Hop-Up kits. He hasn't been active on this forum in a while and his website hasn't been updated, but here's some information on the process:
    http://www.simpsonmotorbikes.com/55cc Hop.htm

    Here's some more information on 60cc from Jaguar:

    AKA: BigBlue
  3. foshizzle01

    foshizzle01 New Member

    has anyone tried this? looks pretty cool. would i have to re break in the motor?
  4. butterbean

    butterbean Well-Known Member

    Yes, you want to break the motor in again. Also, you'll want to put some oil in the cylinder during assembly to lubricate it so the piston doesn't seize the first time you fire the engine.
  5. jogan516

    jogan516 New Member

    spookytooth does not make these kits anymore

    Hello I called spooky tooth and they denied ever carrying them. the they told me that that conversion will never work????

  6. jaguar

    jaguar Well-Known Member

    I bought a number of 55cc top ends from Spooky Tooth but it looks like they no longer carry them.
    this place does: http://www.simpsonmotorbikes.com/55cc Hop up Kit.html
    and yes, it bolts right onto the 48cc bottom end. I had to upgrade from 48cc when I lived in a hilly city up in the mountains. It worked wonders, especially after other modifications.
  7. jogan516

    jogan516 New Member

    Hello Jaguar
    Thanks for the help, but I called them also and they said that they are still on their site, but have been discontinued by the manufacturer. Ant more Ideas on where I could find one. Thank you