Thread: 2003 GP800R question
09-29-2011, 05:46 AM #1
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- Aug 2011
2003 GP800R question
I have a 2003 GP800R. I purchased it this year and it only had 33 hours on it. For about the first 6 times I took it to the lake, it would run 65 mph according to the instrument cluster and do a 7500 rpm. Now it seem like it will run about 57 and 6500 rpm. I have changed the plugs and put in a new fuel filter. I checked the speed with a GPS and WOT it 50 mph. Any idea why it's not running like it did? It has 63 hours on it now. It is completly stock. I checked the compression and the front cyclinder has 115 and the rear has 90.
09-29-2011, 07:02 AM #2
25 psi difference between two cylinders is a lot! Recheck compression.
Does the 800 model have a Catalytic converter? If yes, there is another possible power loss, these Cat con fail early on the three cylinders models
09-29-2011, 07:07 AM #3
Plus, you cant compare a 65mph reading on an OEM speedometer to the 50 mph reading you got with a GPS. Im pretty sure your real top speed with that stock ski should be below 60mph using an accurate instrument like a GPS or Radar
09-29-2011, 07:29 PM #4
It would be a good idea to recheck the compression at wide open throttle if you still have only 90 psi on the rear cylinder it would be a good idea to pull the head and inspect the piston and cylinder walls also check the power valve for damage and proper movement.
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