Idle changing speeds (to its own beat )

[Anonymous]

Re-built the carbs this winter, and all new 0-rings.

When around town, idles fine at 800.
After hot running HWY 10 miles, it idles at 2000 and i hate the clunking into first at the lights.

Sound like vacuum leak ????

Also with full clutch in, throttle of, (approching light eg.) engine idles at same speed as the gear I'm in. Brake to whatevers there, and off the clutch at any point and its back in gear and rpms already at identical rpm, weird.. when eng cool it goes to idle with full clutch.

any help appreciated
Stimpy

[Anonymous]

Most likely just idle is misadjusted. Sync carbs, adjust idle and try again. If the carbs aren't sync'd all your other fix attempts will be create other problems.

[Anonymous]

Thanks,

I have sync-ed them, I have the original Suz sync tool, not sticks, cost me 200 a few years ago but worth it....

all plugs look good, no bad burners...

It runs and idles great except after getting highway hot, PS I have full wind screen on it so it has a bit of reduced air flow... thinking of cutting off leg tabs for more engine cooling....

Stimpy

[Anonymous]

Try backing your idle down.

[earlfor]

Idle rpm is only supposed to be set when the engine is a full operating temperature. Idle cannot be the same rpm when the engine is cold as it is when the engine is at normal operating temp.

Earl

[Anonymous]

I have adjusted the idle screw several times.
Who / cool doesnt matter.
If I adjust hot, it wont idle when cold/ choked or not.

I know a vac leak will cause highter idle. I have new intake boot O-rings but the phillips screws stripping when trying to extract as with the carbs out there is still only 5-6 inches access so little torque can be applied.
Any help getting them out will be appreciated.

Thanks in advance for all feedback..
Stimpy

[Anonymous]

I have adjusted the idle screw several times.
Who / cool doesnt matter.
If I adjust hot, it wont idle when cold/ choked or not.
I know a vac leak will cause highter idle. I have new intake boot O-rings but the phillips screws stripping when trying to extract as with the carbs out there is still only 5-6 inches access so little torque can be applied.
Any help getting them out will be appreciated.

Thanks in advance for all feedback..
Stimpy

In this case, your problem is not that it idles high when hot, it's that it won't idle when cold. Perspective thing.

I'm not the best one to ask about poor cold idling if carb sync and idle don't fix it.

Not sure which screw you're talking about stripping... the boot clamps? ??

Until you get it figured out you could just hold the throttle open when idling cold. That's what the idle screw does anyway.

[Anonymous]

I just removed the intake boots on an 1100 that had sat under a tarp in Seattle for 10 years. The were well corroded. I used Aero-Kroil and an impact driver. All came out except the one the previous owner broke off. Anyway, I don't think you can beat the combination of Aero-Kroil and an impact driver.

As for your idling problem, I'm not sure. I do know that it's a good idea to replace the O-Rings on the intake boots once a decade or so. I have an 1100 that has a similar problem. I haven't got the carbs off yet, but I suspect the intake boots on that one.

[Anonymous]

Hi Karl,

Aero-Kroil and an impact driver... ???
First what is it and is it better than BP-Blaster?
Next, how the hell do I get an iimpact in without pulling the engine ???

even if I just get the impact driver in AND removing the airbox there is still not enough room to swing the hammer for the driver..

any tips ??
stimpy

[Anonymous]

If you have a broken intake screw you are most like loosing vacuum right there, mist some either around it , if rpm go up its leaking there, you really need all the bolts in intake to seal

[Anonymous]

I also get a good smell of gas when off the throttle coming to a stop or toll.. etc.. another leak indicator??

Thanks,
stimpy

[KEITH KRAUSE]

Classic intake leak. You start up and the bike idles OK. After the bike warms up, the idle is too high to be acceptable. You pull over and adjust the idle down to something acceptable but then the next time you start it cold the bike won't idle until you set the idle back up.
This is an intake leak(s), most likely the manifold o-rings or the manifolds themselves. Sometimes it can be loose manifold clamps. With the motor warmed up, spray a fine mist of water and listen for the rpm's to drop a moment.
A good running motor will idle maybe 300 rpm more once fully warmed up. Beyond that, is a vacuum leak or sometimes a mechanical problem such as a sticking throttle valve, etc.
The manifold screws should be replaced with hex bolts. Apply some hi-temp' bearing grease to the o-rings and torque to about 6 ft/lb.

[Anonymous]

thanks Keith,
thats what Ive been thinking, I did spray around the boots with gasket spray while idling hoping to stop up any air leaks but to no avail, of course I cant get into the 2-3 cyl intakes well.
any advice getting those damn frozen intake screws out, cant even get vice grips in there if I strip one other than pulling engine...

thanks all so far...
Bob aka Stimpy

[KEITH KRAUSE]

Those screws can get stuck good. With the limited space to work in, leverage is a problem. The carbs and airbox have to come off. I'm assuming the Phillips screws are gutted inside?
I don't know what tools, etc, you have to work with but here's what I would try. This only works (sometimes) if you have not totally destroyed the screw centers. You can sometimes take a short piece of steel rod that's flat on one end and with a hammer, try to work any stripped material back towards the center of the screw. Work in a circular motion. If you are lucky enough, you have now filled the stripped area a little. Now take the rod (a 1/4" diameter or 3/8" is better) and pound straight in on the screw head. This will help solidify the material you worked back in and also the impact will help break the threads of corrosion. Then take a quality, good fitting Phillips bit and hit it straight into the center. This is an attempt to make a "new" head that might allow you to turn the screw. If you pound the end of a screwdriver in, be careful if the handle is plastic.
Another thing that sometimes works is to make a new "slot" for a regular screwdriver. You can use a cold chisel or possibly a dremel cutting wheel.
Whatever you use to make a new slot, just be sure you have a tool that will fit the new slot tightly.
There are also "easy-outs" but I have no experience with them.
If all fails, you may have to cut into and possibly ruin the manifold(s) so you can get some channel lock pliers around the screw heads. Manifolds are not that expensive and if yours have any cracks they may need replacing anyway.

[Anonymous]

Hi Keith,

the screws ARE original, never had them off my 83, I know, I bought it in crate in 83.. Not stripped, I have not touched them, I tried one screw and it did not budge so stopped there.

I just took her for a heat up ride, got her real hot and downed the idle to 1500, better than 2000, but the idle screw now as loose as she gets....

so thats where im at... so far...

I drilled out the mixture screw caps when rebuilding as 21 years I dont trust factory set anymore.. could I have it too rich?? set all at factory 1-1/2 and synced.
sync was a touch off, but within one line as the o-rings and adapters into the boots I dont think seal great (will get new o-rings for them too)

so the saga goes on....