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Main Area => General GS500 Discussion => Topic started by: lewismug on April 20, 2008, 07:33:42 PM

Title: Sputtering and backfiring at takeoff....
Post by: lewismug on April 20, 2008, 07:33:42 PM
When I first start my bike from cold, I leave it on choke for about 5 minutes, then take it off choke and ride.  When I leave from a stop, it backfires a little in the air filter box and sputters a little but smooths out considerably when I get going.  After a 20 minute ride it doesn't do this.  It takes off just fine and has plenty of power even from a stopped position.  I haven't touched the carbs, air filter, or anything else since purchasing this bike.  It has 5,100 miles on the clock and is an '02 GS500.  Any ideas as to what I should do first?  The bike sat in the po's driveway in the weather for over a year without being ridden.  I brought it home, drained the gas tank, put new gas in and haven't done any work/adjustments since.  I know I should change the plugs and air filter, but carb adjustment scares me.
Title: Re: Sputtering and backfiring at takeoff....
Post by: qwertydude on April 20, 2008, 10:02:27 PM
Most likely from sitting it got varnished, your symptoms don't sound too bad. Run seafoam or fuel system cleaner through it and  within a few tanks it should be better. I'd dump half a can of seafoam in a nearly empty tank, fill up and ride normally till it's empty and repeat with the other half before you replace the plugs you can also ride for a few dozen miles with the choke at half so you also clean out the choke passages. But keep in mind this is a GS, it's cold blooded and can take a few minutes to fully warm up to where it's not jerky. Mine is just fine but when cold I'll get some pops and jerkiness for the first couple of minutes.
Title: Re: Sputtering and backfiring at takeoff....
Post by: yamahonkawazuki on April 20, 2008, 11:05:02 PM
Quote from: qwertydude on April 20, 2008, 10:02:27 PM
Most likely from sitting it got varnished, your symptoms don't sound too bad. Run seafoam or fuel system cleaner through it and  within a few tanks it should be better. I'd dump half a can of seafoam in a nearly empty tank, fill up and ride normally till it's empty and repeat with the other half before you replace the plugs you can also ride for a few dozen miles with the choke at half so you also clean out the choke passages. But keep in mind this is a GS, it's cold blooded and can take a few minutes to fully warm up to where it's not jerky. Mine is just fine but when cold I'll get some pops and jerkiness for the first couple of minutes.
indeed. not really necessary for a carb clean... yet. mine was doin this when i bought it last weekend, ( just came out of winterisation) btu after a tankful and a hard flogging, she purrs now
Title: Re: Sputtering and backfiring at takeoff....
Post by: lewismug on April 21, 2008, 06:04:54 AM
Thanks guys!   :thumb: