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Main Area => General GS500 Discussion => Topic started by: waltermax on May 25, 2008, 07:34:16 PM

Title: Still Running Rough
Post by: waltermax on May 25, 2008, 07:34:16 PM
I've done some searches and got it to a decent point, but it's still idling funny, has hesitation from idle and at 4k rpm.

So, here's everything that I've tried:

1. Carb rebuilt kit (needles, gaskets, etc)
2. Carb clean (twice) Used carb cleaner, and the second time used speaker wire to get inside the jets
3. Spark plugs
4. Mixing screws adjusted to about 2-3/4 turns. I've messed with it all up and down the range w/o a perfect setting

Things I'm considering:
Cleaning fuel tank - Will this really help?
In-line fuel filter - Will this actually help? And does this mean that it filters between the petcock and carb?
Adjust float height - but I don't want have to take the carbs off again, sigh, and I don't know how to measure the float height once I'm there

Any other ideas?
Title: Re: Still Running Rough
Post by: The Buddha on May 25, 2008, 07:42:44 PM
OK I am going to guess here ... the rebuild kit did nothing, it was never needed (I am yet to have 1 carb that needed it in over a 100) the rest is all regular cleaning etc etc ...
I'd suggest you jet it to 40/125/1 washer/3 turns ... I have a kit for that or you just buy it from bike shop.
Cool.
Buddha.
Title: Re: Still Running Rough
Post by: dchrist on May 25, 2008, 08:59:36 PM
+1 for rejet.

once I got the right jet numbers in my carbs all my idling issues went away.

good luck

d
Title: Re: Still Running Rough
Post by: ben2go on May 25, 2008, 09:00:06 PM
Cleaning the tank really helps.Something as small as a grain of sand can foul up carbs.Filters are a must on bikes over a couple years old.The one I took off had been on for a year and had thick sediment in it.It was a clear type filter.Mine is between the petcock and carbs.Have you converted your petcock to non vacuum operation? http://gstwins.com/gsboard/index.php?topic=19363.0 And lastly,yep you can adjust them on the bike but it's a pain in the a$$$.You need a driver bit that fits your float bowl screws/bolts and a small wrench to fit the driver bit.Don't forget to drain the bowls before you start.
Title: Re: Still Running Rough
Post by: beRto on May 26, 2008, 08:36:40 AM
Quote from: waltermax on May 25, 2008, 07:34:16 PM
Adjust float height - but I don't want have to take the carbs off again, sigh, and I don't know how to measure the float height once I'm there

Here's an easy way to measure float heights:
http://www.bbburma.net/FloatHeight.htm (http://www.bbburma.net/FloatHeight.htm)

What is the mileage on the bike? I think that you may experience poor idling and hesitation if your valve clearances are out of spec. The Suzuki maintenance schedule says valve clearances should be checked/adjusted every 4000 miles (6000 km).
Title: Re: Still Running Rough
Post by: waltermax on May 26, 2008, 06:38:22 PM
Quote from: beRto on May 26, 2008, 08:36:40 AM
Quote from: waltermax on May 25, 2008, 07:34:16 PM
Adjust float height - but I don't want have to take the carbs off again, sigh, and I don't know how to measure the float height once I'm there

Here's an easy way to measure float heights:
http://www.bbburma.net/FloatHeight.htm (http://www.bbburma.net/FloatHeight.htm)

What is the mileage on the bike? I think that you may experience poor idling and hesitation if your valve clearances are out of spec. The Suzuki maintenance schedule says valve clearances should be checked/adjusted every 4000 miles (6000 km).

I paid a guy to get the bike running over the winter. He used shims I think to get the valves right, but then one of the exhaust valves broke. So he replaced both exhaust valves, gaskets etc. Could he have set the valve height incorrectly?  Thanks
Title: Re: Still Running Rough
Post by: birdman on May 27, 2008, 10:24:04 AM
I vote float height.  After I rejetted my bike it ran real well the first day.  Went back two days later and it ran like a$$.
Would not idle right and would sputter and die when I gave it fuel.  The choke would make it run but barely.

All the lines were fine and no visible leakage.
I pulled the carbs off and remeasured the floats with a precision steel ruler, not my calipers and found I was too high on the float level by about .08".  Measuring around .45" upside down.  I think I was moving the floats with the caliper method.

reset to .57, reassembled and back to running good.