Revs still hanging GS550E

[tom203]

mikeyc; give that throttle cable plenty of slack- it might even be sticking at times and return spring is not pulling it back. Trying to tighten the clamps on old carb boots can be dubious- recheck. At idle, the throttle plates will close down real far- another guy recently had this problem and was surprised to find this out. A non responsive idle adjustment screw is a sign that something is wrong.

[Dan]

Throttle cable is fine does'nt snag and snaps back, changed vacuum pipe already. Maybe carb pistons not returning could be the fault need to have a look at that.

[Mikeyc]

Better, but not perfect....

I removed the tank and adjusted the throttle cable. I also loosend it up a bit at the adjusterat the hand grip. My hanging idle is much better, but still not perfect. I'm guessing I may have a small air leak, The question is, where is this the likely source? Hint: the bike is running very well other than a slight hanging idle. Another possible clue: it idles well when it is slightly warm, then I ride for a bit and that is when it tends to hang up around 1500 and sometimes 2000, but it will then settle back down a bit. eventually it comes back down to around 1000 rpms. Does this sound like a leak in the airbox?

[tom203]

I removed the tank and adjusted the throttle cable. I also loosend it up a bit at the adjusterat the hand grip. My hanging idle is much better, but still not perfect. I'm guessing I may have a small air leak, The question is, where is this the likely source? Hint: the bike is running very well other than a slight hanging idle. Another possible clue: it idles well when it is slightly warm, then I ride for a bit and that is when it tends to hang up around 1500 and sometimes 2000, but it will then settle back down a bit. eventually it comes back down to around 1000 rpms. Does this sound like a leak in the airbox?

Remember that "intake boots appeared fine" line ? I'd at least retighten clamps, cuz this area is prone to slight leaks. Remember when warm and at idle, vacuum is at maximum.

[mike_of_bbg]

The rubber->metal bond on the boots starts to fail after 30 years or so of heat cycling. If you pull the boots off, give them a good pull and see if you get any movement of rubber relative the the metal mounting flanges. If so, it's time for new boots.

[Mikeyc]

Thanks

I think I may replace the boots (intake) as a winter project. Some of the screws are stuck like you would not believe. I beat on them for hours with an impact driver, & soaked them for days with PB Blaster, and still couldn't get them all out. On the ones I did, the boots and orings were in really good condition. I am thinking my issue might be on the airbox side.

[tom203]

I think I may replace the boots (intake) as a winter project. Some of the screws are stuck like you would not believe. I beat on them for hours with an impact driver, & soaked them for days with PB Blaster, and still couldn't get them all out. On the ones I did, the boots and orings were in really good condition. I am thinking my issue might be on the airbox side.

So you didn't replace all the carb o-rings? naughty! The one(s) you left are probably your problem. Personally, I don't see airbox leaks causing a hanging idle- besides you said the bike "was running very well".

[Mikeyc]

Hi Tom, no I didn't replace all of them...could only get two off, but they were in really good shape, so I thought it was worth the risk. The bike is running really well, I am a bit of a perfectionist (so says my friends) and I want to solve this annoying little issue, which really isn't too bad. I was afraid I was going to break something trying to loosen the intake boots. I just turned 15K miles on the bike.....pretty low for an 82!

[tom203]

Hi Tom, no I didn't replace all of them...could only get two off, but they were in really good shape, so I thought it was worth the risk. The bike is running really well, I am a bit of a perfectionist (so says my friends) and I want to solve this annoying little issue, which really isn't too bad. I was afraid I was going to break something trying to loosen the intake boots. I just turned 15K miles on the bike.....pretty low for an 82!

That's fine, just ride for now and stop being fussy! When you demand more, get back at those remaining two carbs and replace those 28 year old O-rings that have probably lost all of their resilence! Don't forget to replace the screws with allen head ones ( stainless! ) and you have an easier time at next carb removal.