My brother has a kq 300 and has problems with cold starting. It will not crank with the starter, but will start with the pull start. Once it starts the first time it is good to go, but if it sits for a while it has a hard time starting again. Any suggestions?

Thanks

 

Tired battery. Is it cold where you are these days? Try hooking a battery charger up and starting it cold, with the charger on there. If it fires up then there you go. The voltage drop from the starter draw is too much to leave enough for the ignition. What oil you got in there? Anything with more than a 5 in front (as in '10-30') for winter cold is too heavy in any case. Put in 0-30 or 0-40 Motorcycle oil and I bet it starts. Or maybe it's not that cold in Alabama.
Or get a new battery. [img]i/expressions/face-icon-small-smile.gif[/img]

 

That is close to what he thinks it is. It has a new battery, but he thought it could be the rectifier. I think it has something to do with the carb or fuel delivery. Any other suggestions.

 

Its real doubtful that the rectifier is the problem. Have the battery load tested, its the only real confirmation of whether or not its good, age doesnt mean anything. Ive sen new batteries which were bad.
If the battery checks good, try the starter next. It could be rusty or packed with mud, or the resistance has changed due to wear on the brushes.