Hi
Just rebored new wiseco piston put a back together, compression really good, starter motor and battery have problems turning over the engine. When connected up to 2 car batteries turns over and fires up straight away. Can anyone suggest a suitable battery that will fit into bike and have enough power to start. Would a higher voltage battery do any damage? as my son rides this bike and a pull start will not be a suitable for my 6 year old. Please HELP!!!!!!!!!!!!!

 

Let me get this straight, it takes 2 car batteries to start an 80cc 2 stroke? Something ain't right. I would first check the starter motor. Can YOU pull start it ok, or does it feel like it's binding up?

 

Hiya dude
The bike turns over okay without the spark plug in & runs free, Its only when the spark plug has been fitted the battery struggles to turn engine over,add more volts & the engines turns over & starts straight away. I have tried fully charged 12v car battery & this would not turn the engine over fast enough to start it.PLEASE HELP.

 

Well, I don't know much about these sorts of things, I prefer the keck em and go method[img]i/expressions/face-icon-small-wink.gif[/img] But, if the motor turns over fine without the plug, maybe the compression is just to high for the starter motor to turn over. Can you pull start it ok, though?

 

Your problem lies in the starter.Sounds like the brush's or armature is worn. Get another starter.
You may indeed need a new battery, there is no other battery with more power. 12 volts is 12 volts.Get the stock replacement if needed.
Even on a modded motor, the LT80's starter is strong enopugh to spin it with no problem.