08-19-2008, 10:15 PM #1
think this is a power valve problem?
i took my 04 gp1300r out today and noticed if im crusing around 5000-5500 rpm there is a "power surge" imagine an idle surge just at a higher rpm. if i give it more throttle the problem goes away and below 5000 rpm there is no surge. it only happens around the time the valves should open. its not showing any codes besides 01 which is normal. i also notcied that it is only producing 11.8 volts at idle, shouldnt it be in the 13-14 volt range? could my power surge be related? (not enough amps to open the valves unless the engine is turning higher rpms) could carbon build up cause the valves to "stick" and not be able to open all the way? i have never pulled the covers to clean them or anything and it has 80 hours on it
08-19-2008, 10:24 PM #2
08-19-2008, 10:37 PM #3
08-19-2008, 10:41 PM #4
You have a aftermarket tach,what rpms are you turning and speeds(gps)
08-19-2008, 10:44 PM #5
dont have a tach or gps, but the stock tach is close enough to tell that it happens when the valves should be opening.
08-21-2008, 04:13 PM #6
08-21-2008, 04:57 PM #7
That RPM is right about where they kick in, so I'd say it's a likely culprit.
08-21-2008, 07:21 PM #8
- Join Date
- Jan 2008
sounds like the valves are operating the way they are supposed to. At 5000rpm they are opening giving you that surge feeling.
IF you DON'T feel a difference around 5,000 to 5,500 RPM then you may have a problem.
The stator only puts out about 1 amp at idle. You won't notice any significant voltage increase until around 3,000rpm on you battery.
Hope this helps,
08-22-2008, 08:30 AM #9
so you are saying the surge is normal? i never had the problem before it overheated and blew. i took the cover off of the back cylinder and there was some good build up but i dont think it was over the top. my only worry is there was fluid puddled under the valve. dont think it was water, it might be wd-40 or fogging oil from where i sprayed everything down when it was apart to keep it from rusting, and when i started it up for the first time some of it collected in there. im going to clean everything up and see if it helps
08-29-2008, 08:49 AM #10
got to thinking, when my engine overheated i bought a head from a memeber on here, my gpr is an 04, what if the head is from an 05 or greater? could this bump the compression up enough to cause slight detonation, giving me this surge? it also has a slight pop/backfire when crusing 2500-4000rpm. is it all related? when i did a compression check all three were over 120lbs, and i thought it was just gauge inaccuracy (all three showed the same +/- 2-3lbs). im going to try some premium and see what happens. i might try midgrade too since my compression isnt 140+
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