scooter will not restart after being ridden and shutoff By lincolnlsc (Read 527 times)

[lincolnlsc]

Ride the scooter to where you are going shut it off go in for 10 or fifteen min, come back will not restart, unless you wait a couple of hours. when checking found we loose spark. Tried 3 known good cdi, known good coils. The neat thing is if you put the cdi in the freezer for about 10 min reinstall, will start right up like nothing is wrong. None of the good cdi will restart while cdi is in the freezer, after it restarts, other CDIs will work. This a new 50cc 4 stroke engine, less than 25 miles, The scooter is a baja sc50 the original engine had bad crank and transmission bearings. Had to rewire from DC to AC for the new engine. Any one have any thoughts on this.

[alleyoop]

have you checked the valves, they may be to tight and when hot are a left a little open and you will not have enough compression until they cool off and seal.
Alleyoop

[reef2065]

I had the same problem and it was the valves...New valves will sometimes tighten by their self. Mostly the exhaust valve

[bhinch]

Yes, the valves need to be adjusted. The reason they are off is the initial adjustment was done incorrectly.

[halfwitt]

Is there a thread on this forum that explains in detail the process of adjusting the valves? I have watched youtube videos and they have had the basic info, but want more detailed understanding of what to watch out for and what NOT to do, etc...
I have a 150cc GY6 Roketa 2011 four stroke with about 6500 miles. Bought it new to avoid problems, got more for my trouble. B-|Struggled with the thread problem for months before I glimpsed someone mentioning the valve adjustment. up to that point all the mechanics I spoke with were all, fuel, spark, carb issues. I rebuilt that carb 6 times in a couple of months trying to make it work. Adjusted the valves and it ran fine and started like a dream. This after draining batteries, jumps, four mile walks/pushing the scoot home, etc... I was ready to drive it into the canal, just couldn't start it when I felt that way.
Please share links (if you know of them) that lead to instruction on repairs with your advice. It saves much time and trouble seeking out information on the forum/elsewhere.
Thanks for all.

[alleyoop]

Alleyoop