High rev sysndrome

Scorpio1963

Scorpio1963

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So at idle and before I go for a ride my idle is fine.I rev it up and it falls back down.Go for a ride and while Im riding the rvs start getting higher and higher to the point I had to shut the bike off.I would restart idles find then it starts again.I sprayed wd around my manifolds and airbox tubs no change wht in the world could be causes foor this.
 
spray the butterfly throttle shaft seals, common area that is often missed by people diagnosing. If you spray while the idle is high it should drop as it is sucked in and ignited by the engine.
 
I watched a video online last night I beleive its the carbs out of tune my attempt at bench syncing them was way off that will be remedied later today.
 
Scorps, another cause of this is when you pull your carbs and accidentally rethread the throttle cable in the wrong way, it can have tension put on it causing the high revs. Make sure the carb is really truly reinstalled correctly, including and especially the throttle cable has no pinching or isn't trapped anywhere. My bike hinted at this because I'd make 3 point turn to park and when I maxed the steering the bikes idle would change, because the tension on the sleeve around the throttle cable would change. turns out I'd rethreaded it's way back to the carb incorrectly the very first time I'd removed them.
 
I made sure the throttle cable was in correctly.It would start reving going down a straight road and then sometimes die.It has never acted crazy like this before.They are offf the bike right now.I made sure I didnt have any vacume leaks at the manifolds also.
 
Oh I forgot 1 thing,I had made new gaskets out of gasket material since the old ones were very compacted.I didnt remove the old ones I just put the new ones on for the fuel bowls and tightened them down.Would this have an affect on my float level?I did notiice small puddle of gas in the venturi and airtubes were wet
 
Figured out the problem yesterdaY IT WAS THE CABLE STICKING.I took it off my carbs and would watch the cable as I snapped the trottle it was hanging up and not going back into its place.I squirted some WD inside the cable works much better.Its amazing how we tend to skip over the obvious.:banghead:
 
You guys experiencing problems with erratic or high revs check your cables.I took mine completely off and it was full of white powdery corrosion stuff.Remember these bikes are old and condensation has a tendancy to build up in these kinda places.After you remove the cable get some kinda of lubricant graphite,wd,liquid wrench squirt down inside you cable.Move the wire back and forth as the work the lubricant into the wire cable.Since nobody was nice enough to inform me:wtf: I thought I`d share.
 
Finally catching up on scheduled maintenance are we? :)

I was told to always check the throttle before each ride. Just give the grip a twist and make sure it snaps back with a thunk. If not, find out why before riding! And while you are at it, give the brake and clutch lever a squeeze, check the oil, lights and tire pressures. And the gas level!
 
Its the first thing to check if the carb is hanging up at all. Also:agree: with dave.
 

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