I've posted many times regarding my choke, but here is something I didn't post. Just wondering if it's normal.

I use full choke to start my bike and keep it on.
It starts and the RPM's stay at around 1400.
A minute or two goes by, full choke still on, and all of a sudden my bikes starts to die.
If I don't give it throttle, it will.
I decide to give it just a little throttle when it's about to die and presto, the RPM's go to about 4500-5000.

If the bike is cold with full choke on, and I give it throttle, it will go back to the 1.4-1.5k range and stay there until warm, then it will rise.

I have concluded that my bike will not instantly go to the 4-5k range unless it is semi-warm.

If it is fully warmed up, I let it sit for a hour, then decide to ride it again, I have to choke it, start it, then flick throttle to get it to go up to the 4.5k range.

I don't think it's normal.

Im assumnig you have done the norm like valve clearance check/adjustment, carb cleaning and carb synch-ing?

Sounds like a leaking  diaphram or tight valve issue.

On a cold day I gave my 97 GS full choke when starting and walked away to put on helmet, gloves, etc and within a minute or so it was starting to race away and I had to get to it and close the choke some to bring it down from 3-4k rpm to below 2k rpm.  It was pretty much the same way for the 4 years and 80k miles I rode it here in NE Ohio.

On the other hand my 02 GS would/will start up on a cold day at a similar 13-1500 rpm idle as the 97 but it never speeds up as it warms.  In a minute or so it begins to bog down with decreasing idle and will die if throttle is not opened or choke closed some in time much the same as you describe and it's been that way for the 13 years and 97k miles I've ridden it so far.

That and other considerations indicate my 97 with the older 2 circuit carbs was considerably leaner running than my current 02 GS is with the newer 3 circuit carbs.  Both bikes have gone all the way for the 177k I've run them with completely stock carbs.  I think both were/are normal.  The 02 still runs as good as new if you disregard the high oil consumption at high speeds after you get higher milage on them.  Somewhere between 50k and 80k miles the 500cc GS engine changes into a 500cc oil pump.   

I have a slimier issue. On my 01 when I start it with full choke it will idle at 1400 then try to die after a minute. I have to keep the rpms up or it will. after it warms up its fine. Idles perfect runs fine but i havent been able to figure it out either.

Quote from: gsJack on February 22, 2013, 09:56:57 AMOn the other hand my 02 GS would/will start up on a cold day at a similar 13-1500 rpm idle as the 97 but it never speeds up as it warms.  In a minute or so it begins to bog down with decreasing idle and will die if throttle is not opened or choke closed some in time much the same as you describe and it's been that way for the 13 years and 97k miles I've ridden it so far.

I have this exact thing on my '91. If I don't half close the choke after I start it, it will stall shortly.

Hm, I thought with the choke on full, with a cold start, the bike should instantly go to 4k-5k?

Quote from: Zethioth on February 23, 2013, 03:31:41 PM
Hm, I thought with the choke on full, with a cold start, the bike should instantly go to 4k-5k?

Thats how my choke works.

Check the choke punger. I know one of them on my project bike was worn completely through the brass so only 1 side would choke.