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Main Area => General GS500 Discussion => Topic started by: xanderhaymore1000 on February 10, 2018, 11:03:50 AM

Title: GS500F Idle Problem
Post by: xanderhaymore1000 on February 10, 2018, 11:03:50 AM
Hello,

I have had a ton of issues with this bike and as of a couple days ago it's finally running like a champ. One issue, whilst riding, even after 30+ minutes (So it's not cold), sometimes the bike stalls when I come to a stop. Yes, I'm pulling in the clutch on the stops. It's like the engine bogs down and struggles to idle a bit. Any ideas on how to fix? I'm not super experienced with carbs but I think if I remember correctly there's a way to adjust the idle mixture, is this hard? Any suggestions are appreciated!

Thanks for your time
Title: Re: GS500F Idle Problem
Post by: The Buddha on February 10, 2018, 11:27:14 AM
Find out if its lean or rich @ idle via plug pull.
These bikes stall when rich, and idle hovers when lean. If the plug is black and sooty you could try to check the floats or if you have some other problem. Floats tend to wear and get high and get it too rich and cause your problem.
Cool.
Buddha.
Title: Re: GS500F Idle Problem
Post by: mr72 on February 10, 2018, 02:26:41 PM
Contrary to what Buddha says, it's probably lean at idle. It's not hard to adjust buy it may need a bigger pilot jet.

The reason they "hang" when lean is because the idle is set too fast to compensate for lean idle. But without compensating a lean idle will stall. 
Title: Re: GS500F Idle Problem
Post by: The Buddha on February 11, 2018, 03:47:26 AM
But Mr 72 - Its holding idle when cold, it stalls after 30 min. That should be rich. However he may be choking it and riding it for 20 min ...
Cool.
Buddha.
Title: Re: GS500F Idle Problem
Post by: mr72 on February 11, 2018, 05:51:22 AM
I didn't read that as it ONLY stalls at stops after it's warmed up.

Still stalling at idle no matter the temp is most likely lean. You'd have a hard time getting a gs500 to idle nearly rich enough to stall. I bet it take a pilot jet over 50. 3 and a half turns out on a 40 pilot is still slightly lean.

A plug check is not that useful IMHO. They always come out black on the ring and some shade of tan on the electrode unless the bike simply will not run unless on choke. Plus you only adjust mixture of the pilot circuit so you'd have to warm the bike up, clean the plugs really fast, then let it only idle for like 5 minutes to get the idle condition to show on the plugs.

Unless the bike is modified by changing jets way up you can almost always assume mixture is lean. IMHO. A stock gs500 is lean across the board and it takes more than 40/127.5 jets to get it to run rich. I am currently running 40/127.5 and it's dead nuts perfect except it's slightly lean on transition off pilot. IMHO again. I suppose every bike could be different, but it is hard to err on the side of rich by accident.
Title: Re: GS500F Idle Problem
Post by: The Buddha on February 11, 2018, 09:10:10 AM
A 89-00 will get rich @ idle and stall with stock jetting even because its floats wear and that makes them go high and when you brake it can dump a nice blob of 1/2 atomized gas into the intake. Will get rich, easy. Also a 42.5 pilot will leave you rich enough to choke on, some genius did that to my 89 - my first GS and my 5th bike overall, and that bike taught me nearly everything I know about GS'es ... Anyway that fool didn't know that 42.5 starter jet aint 42.5 pilot, obviously I had no clue for years.

The 01+ carb wears floats much slower than the 89-00, so I'd guess its possible you're rich.
OP - Please check plugs, and check float level.

Cool.
Buddha.