Choke stuck open?

[Guest]

So this has been happening since I've got my gs1000 back running.

The bike starts ok with choke open. No need for throttle.

Then when I close the choke I noticed it was still reving pretty high. I assumed it needed the idle adjust knob turned...but later realized that it wasn't that....

After a while of riding, say 5 minutes, the engine abruptly seems to go back to normal, as if I'd closed the choke...then idle is where it should be.

So I took off the gas tank, thinking I'd be able to see the choke stick open when I pulled the lever. All seems normal (this is with the engine not running). I pulled and released it a bunch of times and it seems to return to closed every time.

I would appreciate any ideas.

UPDATE: Just typing that out got me thinking the right way... The gas filter I got was a lot bigger than the one I had in the bike previously. So I'm thinking, maybe the filter or fuel line is pushing up against the lever at the carbs when the tank is installed. Sure enough that huge filter is really close to the lever and it's pretty likely that when I install the tank, and push the fuel line back in a bit to get it on the petcock, that the filter is getting in the way of the lever.

So, I'm going to try a smaller gas filter.

[chuck hahn]

Take the carbs off so you can remove the choke plungers.

The critical part of the plunger is the rubber seats in the ends of the barrels. Be sure the tip that fits into the hole in the bottom is straight too.

What I do for sticky ones is one of two fixes.

Fix one.. take a NEW green dish scrubbie and roll a piece up and scrub the plunger hole to remove any scale or burrs.

Fix two... some 1500 wet sand paper and a few twists around the brass barrel itself to smooth and take a few thousands off it so it slides nice and smooth. Whatever you choose ( sanding the barrel is the easiest ) check each plunger in the carb before reassembly for smooth and reliable operation.

[chuck hahn]

Also...when you tighten the lifter up, look to see that the plastic thing is centered in the forks and not rubbing on them anywhere. If they bind against the lifter they can hang up from that as well.

[RobertGS]

Thanks Chuck,

If it's still sticking at all with the smaller gas filter I'll be needing your instructions big time.

It's funny how just plain wrong it is for the bike to be idling somewhere unusual. I wonder how many rpm's off normal it needs to be before a rider notices it? I'm thinking not very many.

[chuck hahn]

Even with my tin ears, a few hundred is very noticeable. As you get experienced with the way a GS engine sounds its sort of like second nature after a while. Just by listening you can hear what she is telling you is wrong....usually.

Sort of like a baby cant talk but you figure out what they are saying.

[cowboyup3371]

As this sounds a lot like a hanging idle, have you checked for air leaks at your intake boots?

[Agemax]

the choke plungers are operated by a mechanical linkage. if one shuts they all shut. you can look at #1 and #4 carb and see if the plungers have shut without taking the tank off.

do you have a lever choke or a cable? if cable then yes the fuel filter could possibly stop the chokes from closing fully as the cable will just bend but if it is a lever choke then you will be able to feel if the choke is shutting fully when operating the lever.

i am thinking air leaks at manifold as well..........

[RobertGS]

When I got the tank off I noticed I really didn't need to do that to check if the choke was closing. It's a cable. ....Now that the tanks off I'm going to take the opportunity to put in a new fuel line and filter.

I'll check for air leaks too.

Thanks everyone.

[Agemax]

you shouldnt bother with the in line filter, the petcock has its own filter inside the tank.
most in line fuel filters are renowned for not flowing enough fuel and/or blocking up too quickly.
clean the petcock filter in the tank and it will be fine

[RobertGS]

Thanks I guess I just assumed the in line filter was a standard requirement. I admit to being a bit nervous about leaving it out, at the same time as wanting to see how the engine runs without one.

I cleaned out a cruddy tank liner which is most of the reason for my concern...though I think I did a pretty good job with the clean out of the tank. And the petcock filter is clean and intact.

[Nessism]