I've been thinking that the engine on my sons bike just needed to be broken in but we're now on the fourth tank of gas and it just doesnt seem to reach full rpm's when under load (riding). It revs up good at a stand still though. Its a 49cc slant head kit from BGF and compared to the engine on my bike his is 5-6 mph slower and need far more time to get to speed- max is 21 while mine reaches 26 fairly quickly. Upon first start up there was alot of oil coming out of the pipe. Not much now but strange. I will take it off and clean it out today and see if that helps. His kit came with a 41 tooth sproket so by all rights (engine specs show more power than mine, regular head) he should be faster than me. I just put a 44 tooth sproket on his (now we have the same rear sproket) thinking the power to weight ratio must be off and that wasnt letting the engine "rev up". The larger sproket helped with acceleration, a little, but no higher rpm's out of it. Any idea's as to what the problem is? Maybe the engine is just slower than mine. It is upsetting him that I can pull away from him so quickly, I will putting a sbp chamber on it soon and I'm sure that will help but out of the box his engine should've been more powerful.
Both have the ngk plug, good spark plug wire etc, basically the same except his carb is different having no intake manifold and slightly different case, and of course the slant head. I have both engines tuned pretty good- nice tan color on the plug. Any suggestions would be appreciated.
Both have the ngk plug, good spark plug wire etc, basically the same except his carb is different having no intake manifold and slightly different case, and of course the slant head. I have both engines tuned pretty good- nice tan color on the plug. Any suggestions would be appreciated.