Since I'm new to the four-stroke world, I need some assistance with a problem I'm having with my son's DR50. I replaced the piston and rings a couple of weeks ago and the engine would not start...no spark. I discovered the blue/yellow wire had been broken behind the flywheel. I fixed the wire yet the engine still won't start but do have spark. I've double-checked and the timing is correct, and I'm assuming the electrical is good since there is spark. What's my next move to get this thing running again for my son?
- Spark plug gap. - Valve gaps, intake and exhaust. - Carburetor/Air filter, inspect and clean - Head gasket, check for leaks(for example, kick start the bike, and at the same time feel for air escaping around the head gasket)
Hopefully you didn't lose any of the oil seals that go on the cylinder, including the one with the metal ring. That one w/ the metal ring may cause compression to escape if it's missing.