[jimd]

runs great on the startup but after 15 mins it bugs down and wont stay runing. if i let it sey for for a while it will run good onse more

 

[tdgbigfoot]

Perhaps a fuel pump issue, if not the carbs.

 

[jimd]

dont no when it worms up if pull the middle plug wire it runs the same

 

[Abbott911]

dont no when it worms up if pull the middle plug wire it runs the same

Then your middle cylinder aint firing. Either that carb is dirty, your cdi box is going, or you just need a spark plug.

 

[jimd]

tried new plugs cleand the carbs dont know about the box

 

[Sledman74]

COULD BE TORE FUEL PUMP DIAPHRAM

 

[MicahMan]

its probably the computer cause the 650 middle cylendar does not fire untill a certain rpm range. if it dont kick in id check the coil or test the computer. there are a few guys on here that know how to do that. let me see what i can come up with.

 

[MicahMan]

either that or how hot does it get? maybe after a while it gets to hot and the computer kills it

 

[Ugly_old_Poo_kid]

Have you done a compression test?

its probably the computer cause the 650 middle cylendar does not fire untill a certain rpm range. if it dont kick in id check the coil or test the computer. there are a few guys on here that know how to do that. let me see what i can come up with.

He already said it was carbed..

 

[MicahMan]

my bad i must have overread that part.