1. L

    Blow Piston Ring?

    Hey Everyone, Happy Fall! I was bombing down a hill at WOT on a two week old 66cc/80cc bike engine when the engine suddenly died brining me to a complete stop. White smoke was coming out of the air intake. When I pulled in the the clutch to roll the bike back to my house, the sound of the...
  2. Sitherus

    Engine Trouble engine sounds like its gonna start but doesnt

    Last year I built this engine. I replaced the magneto and installed it backwards. When i corrected it it has yet to start. Here's what its doing. - It has spark, It has compression, it has gas and I mixed 1 standard small bottle of 2 cycle oil with 1 gallon of gas. the carburetor is getting air...
  3. inspectorcritic

    How Does One Correct Low Compression?

    Solution probably gonna be tuff pull the low end apart don't have a machine shop or a press.
  4. inspectorcritic

    What Should the Compression Be?

    I just bought another new motor from California Mototr bikes first 2 or 3 days was superiors to others no speedometer but felt like running 25-28MPH out of the box is pretty good then I don't know if I miss with the head with a lose nut made a exhaust echo had to drive it 3/4 mile to Home Depot...
  5. J

    Bike was running good I was adjusting carb and it died and won’t start help quick!

    Hello so I recently bought a 66cc gas powered bike and I’ve had quite a few problems that I worked out by myself but now I need more help I had the bike running great and I was adjusting the carb cause it idled to high and then it died and now it won’t start and I have no compression I put my...
  6. DuctTapedGoat

    Compression Loss Repair #514

    So I was about to ride and bogged out. Checked seals, checked head gasket and it looked fine and decided to check piston rings. But what is this embedded in my head? Looks like a piece of roller needle bearing from the piston! Further investigation. Jug damage, piston damage...
  7. DuctTapedGoat


    So I'm out riding Thursday and I feel a loss in compression, felt like an immediate drop in performance 50%. So I finish the ride home and check: Seals appear fine. Gaskets appear fine. Rings appear fine. Now it won't start. What else could cause a drop in compression, when I roll the bike...