a friends klr......

[Rick B]

I've got a 2003, 650KLR and after I travel a few miles at 70mph or so it begins surging. If I keep it up it begins backfiring and stalls out. The plug is pretty new and I've changed out the fuel line. Could it still be a fuel starvation problem or should I be looking elswhere? Any suggestions? Thanks

[tomatocity]

The vacuum line could be crimped or partially collapsed. Its old and one end lives in a hot area, replace it. This vacuum line feeds the fuel petcock with a vacuum actuated diaphram. Check for debris in the fuel tank. Run some SeaFoam for a tank or two. Clean the air cleaner. Standard maintenance that all of us should do. Tim

On Fri, Jul 15, 2011 at 8:17 AM, Rick B wrote: > ** > > > I've got a 2003, 650KLR and after I travel a few miles at 70mph or so it > begins surging. If I keep it up it begins backfiring and stalls out. > > The plug is pretty new and I've changed out the fuel line. Could it still > be a fuel starvation problem or should I be looking elswhere? > > Any suggestions? > > Thanks > > > [Non-text portions of this message have been removed]

[John Biccum]

Check the carb vent hose, if it has liquid gasoline in it your petcock diaphragm has failed. This hose should be dry. A failed diaphragm means that the carb bowl will empty at speed, resulting in the symptoms you noted. Replace the petcock diaphragm or fit a manual petcock conversion or an aftermarket petcock (e.g Pingel). From: DSN_KLR650@yahoogroups.com [mailto:DSN_KLR650@yahoogroups.com] On Behalf Of Rick B Sent: Friday, July 15, 2011 8:17 AM To: DSN_KLR650@yahoogroups.com Subject: [DSN_KLR650] Surging and backfire I've got a 2003, 650KLR and after I travel a few miles at 70mph or so it begins surging. If I keep it up it begins backfiring and stalls out. The plug is pretty new and I've changed out the fuel line. Could it still be a fuel starvation problem or should I be looking elswhere? Any suggestions? Thanks [Non-text portions of this message have been removed]

[Stephen H. Reichman, Sr.]

Does not answer the backfire part but; How many miles on your current chain? I experienced surging and pulsing on decel and attributed it back to a worn counter sprocket (teeth had a hook shape to them) and a stretched chain (chain had about 34,000 on it). I maintained and kept the chain lubed but still age/use took its toll. It was very pronounced on the highway and at70 mph and deceleration. [Non-text portions of this message have been removed]

[Rick B]

I've got a 2003 650KLR. I'm having a problem with it surging and backfiring. It happens after I've ridden it down the highway a few miles at around 70mph. I'm using a 14 tooth front gear so the RPM's about 5000 at that speed. I'm at 6000+ but I've been double that and then some so I don't think that's it. I've replaced the fuel line, the plug is pretty new and the air filter's clean. Could somebody suggest a few items I might want to check? The backfiring leads me to think that it isn't fuel starvation, but I'm not a mechanic. Your help is appreciated, with the price of gas it's gotten to be my first choice of tranport. Thanks

[Ronald Criswell]

Has a problem with heavy vibration at 70mph and above but runs fine at slower speeds. Mine is smooth as glass between 70 and 80 mph. I think his doohickey spring is broken or not enough tension and maybe worse. He did the doo a couple of years ago. What do y'all think? He used to take it to track day back when he had fatter tires and a 17 inch on front. He regularly over reved to 8 grand. I told him I didn't think that was a good idea. It has relatively low miles compared to mine. Criswell