i just got my yfz back from an top end rebuild and after i ride for a about 5 minits then stop it idols high for about 30 seconds and then goes down to a normal idol speed. what could this be and how would i go about fixing it?
thanx for any help

 

Idle adjustment screw. Lube throttle cable. Sounds like there might be an air leak too, maybe at the head gasket.

 

how would i go about checking if the headgasket is leaking?

 

I have a feeling you may have an air leak too. You can always do the old standby method. Take some starting fluid and spray it at the area in question with the quad idling normally. If there is a leak, the starter fluid should cause the engine to temporarily rise in rpm.

 

exactly what he said.

 

I don?t have any of this starting fluid, will wd40 or some other sort of flammable spray work? And where should I be spraying this I have no clue lol and if I do find the air leak will I need a new gasket or tighten it or what? It seems to be worse, when ever it is cold it runs fine but after five mints it will rev high for about 30 seconds after I let off the gass
O yeh and is it ok if I ride it like this? thanx a lot for the help

 

They might of torqued your head gasket down wrong, if its too tight or loose it will cause a leak. So you might not to replace it if thats the case. Starting fluid is available at all auto-zones and murrays, any car place like that. Spray it at the crack at the top of the head first, then do the bottom one. Another thing is that the quad heating up might cause the leak, cause the metal expands, that would be if it was torqued down wrong too.

If you dont have the tools or knowledge, i would take it back to whoever did your rebuild and tell them that your having probs and to check it over.

 

well, first try just adjusting the throttle screw, sometimes its something little like that