Hi idle

Hello guys I need your help I have a 1985 Yamaha xj700n airhead. My problem is high idle she's Idol in after she runs for awhile the idle begins to creep up to 4000 RPMs I thought it was the seals I ordered and installed aftermarket throttle seals from Lenny and I used silicone silicone grease in there installation still idles High I have used starter fluid sprayed it all around the boots sprayed it on the throttle seals themselves sprayed it around the boots where they meet the cylinder head that's when I got results the idol died the approximately 500 RPMs but crept back up to 4000 guys I'm going nuts trying to figure out where this vacuum leak is could someone please give me some suggestions

 

Okay , you state you replaced seals...did you break the rack split the carbs ? Or only replaced outer seals ? A rise in idle after engine heats up is either your synch is off slightly ,or you have a small vacuum leak. I would suggest likely source is to check the vacuum caps , install new caps ( auto zone sells caps ) . Check your boots coat with RTV if signs of weather cracking is visible. The last item your boots gasket maybe shot , if you remove boots , be carefull the bolts tend to snap off. Replace gaskets , put anti seize on the bolts on reassembly . Cheers

 

Yes Jake fixer I spent the carbs apart and replaced all the seals like I said I use silicone grease but I will do the rest of what you suggested thanks man I'll keep you posted

 

Things that will cause a high idle;
Vacuum leak
Improper carb sync
float levels set too high
choke plunger not sealing on one or more carbs
idle mixture too rich
binding throttle cable

 

if idle drops when spraying around carb to manifold boots it could be loose boots or not sealed to head or clamps to carbs are not on correctly.

your boots have gaskets those could be bad

https://www.partzilla.com/catalog/yamaha/motorcycle/1985/maxim-xj700n/air-cleaner