Carb rebuild/still won't idle.

[Guest]

I'm thinking now that the only thing it could be is an intake leak. My boots are all soft and pliable, but I can't think of any other alternative.

Cleaned the carbs, replaced the o-rings and synched them. Went for a 60mile ride two days ago, and it was hard to start then. Tried going for another ride this morning, and it still wouldn't idle.

Bike started right up, and idled with 3/4 choke for about 10-15 seconds at 1100rpms, and then died. Wouldn't start again, be it with full or no choke. Had to pop-start it, and even then, with the choke at many varying degrees, she wouldn't idle, I would have to blip the throttle to keep her from dying every second or so. Actually just helped to keep the throttle on very slightly.

With no choke, she would die almost immediately, unless I kept the revs on, on, on.

I know that throttle cancels choke on these bikes, but I'm just telling you what I had to do in order to keep her from dying.

Doing this for about two minutes or so, I could get her to idle with no choke at around 1100rpms or so. Perhaps a bit less. When fully warmed up, she'll idle around 1500rpms or so. Perhaps a bit more. If I give her gas while idling, idle will climb to 1900rpms or so for a bit.

To me, there's nothing left other than an intake leak, despite how nice and new-looking and soft the boots are. Despite the fact that the idle doesn't change with the mist test.

Can you guys confirm my suspicions before I go and slap down $100 on new boots?

Thanks,
Mike

[UncleMike]

Just for the hell of it, I just did the WD-40 and watermist test again, and no change in idle whatsoever.

I do, however hear a venting sound from the gas-cap, whenever I put the bike up on the centerstand, or take it off from the centerstand, usually when it's been in the sun.

I've taken the cap completely apart and cleaned it, even though it looked spotless to begin with. But it didn't change anything.

[semerm]

Mike- Did you check to see that you have fuel flow? Is there an in-line filter that may be clogged or the fuel line kinked? Will it take full throttle at all? It sounds lean to me.

[robinjo]

Did you properly adjust your idle mixture screws?

[UncleMike]

Yeah, I tested the petcock before the carb rebuild, and it was great. Giving it gas it'll do fine, and once it's warmed up enough to run, it's great.

Occasionally, it'll die when coming to a stop off of high rpm's, but it didn't do that today.

[UncleMike]

Did you properly adjust your idle mixture screws?

As much as I could, although they didn't seem to make much of a difference in the idle. There would be one position where the idle would go up slightly, so I'd leave it there. All other positions for all four screws would either show no change, or would make it want to stall out.

This also leads me to believe intake leak.

[GSstiny]

Sounds lean to me too. Engines usually richen up to some degree when warm. Also are you sure the float heights are good?

[UncleMike]

Sounds lean to me too. Engines usually richen up to some degree when warm. Also are you sure the float heights are good?

All were set to 22mm.

[UncleMike]

One thing I (stupidly) didn't do, was replace the fuel and vacuum line from the petcock to the carb.

[Slash]

Dude, that sounds almost exactly like the problem I had with my GS... first of all for your gas cap... make sure it's not actually on backwards... because you can do that and it doesn't vent right and your bike will run like **** and you have to keep it revved a LOT... and if that's not it... adjust your "idle adjustment screw" that's not your carb mixture screws... it's a different screw that ((on mine at least)) is under and in the middle of the carburator... I'm sure you're bike will have one...

I know how much of a bitch that problem can be, having to keep it revved all the time. I'm just a kid so I'd pull up to a red light revving my engine like mad and some guy next to me would burn out when it turns green, thinking I want to race... just check your gas cap so it's not backwards((Mine has an arrow that points forward... yeah I was stupid enough not to notice...)) and look for that idle adjustment screw, it's really a life saver...

[UncleMike]

Cap is on correctly, and the idle adjustment would work, but I'm pretty sure I've got a lean condition which I think is resulting from an airleak that causes the idle to rise significantly, so if I have the idle at a place where it will easily and steadily idle when cold, the idle will be at 2500rpms when hot, and that's unacceptable.

[UncleMike]

That last post makes me sound like a jerk. I'm sorry.

It's not that I'm not a jerk, I was just kind of thinking out loud there for a second.

Regardless, as Earl says, the boots are old, I should replace them anyway, and then I'll go from there.

Thanks, man.

Mike

[Slash]

No worries, just thought I'd throw in what little I know... I've had extreme carb & idle problems with my bike, but I don't know as much as anyone else on this site... so listen to them, I'm still learning... good luck man

[UncleMike]

No worries, just thought I'd throw in what little I know... I've had extreme carb & idle problems with my bike, but I don't know as much as anyone else on this site... so listen to them, I'm still learning... good luck man

Thanks, brother.

[Poot]

if its just the fact that your idle is rising after you heat up the engine by riding, then that is normal, however its not usually that much of a difference.

i usually have to adjust the knob once ive been riding for more than 10 minutes depending on the temp.


POOT