Got my buddy's BF 650 back in the shop. This time the complaint is that it will start right up cold and idle BEAUTIFULLY...until you give it the throttle. It dies, and you have to play with the throttle to get it to start. It then runs VERY ROUGH and quickly dies. Let it sit twelve hours or so and it will repeat the process.

Pulled the plugs--both fouled. Valves are set to correct specs. Believe the carb or carbs are gummed up---found oil surrounding the seal on the air filter in the air box when pulling apart. This machine has about 670 hours on it and is well cared for. Am I at the point where I have to pull both carbs and clean them and install rebuild kits? Would like opinions. Doing this as a favor for my friend and want to get it right as he had it to a local Kawi dealer several times and they allegedly could not solve it. I assume these carbs must be synched by the throttle shaft-guess I'll have to figure that out as well.

My long experience with small engines and farm equipment did not prepare me for the world of ATVs...

Help appreciated!

Tom

 

Plenty of videos on youtube that may help. Plus one on synchronizing a BF750,don't know if it's the same as on the 650.

 

Just clean out the carbs, at such low hours the jets, needles etc shouldn't be worn. However fouled plugs and a reluctance to start warm sound like too much fuel, so check air filters and choke mechanism first.