need help reading piston burn pattern
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Re: need help reading piston burn pattern
Tested my bike this afternoon after fixing the cylinder gasket leak and putting a fatter needle and it has improved a lot. Almost eliminated the stalling when quickly accelerating. Thanks to mrrigs for the advice. Afterall this is just a tuning issue. The ignition switch is just okay. Gonna find another needle that is yet still fatter.
Re: need help reading piston burn pattern
Just to clarify, when you say fatter you mean a thicker needle like mrriggs suggest, correct? Not a fatter fuel curve, as is normally meant with the word fatter?bladefrost wrote:Tested my bike this afternoon after fixing the cylinder gasket leak and putting a fatter needle and it has improved a lot. Almost eliminated the stalling when quickly accelerating. Thanks to mrrigs for the advice. Afterall this is just a tuning issue. The ignition switch is just okay. Gonna find another needle that is yet still fatter.
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Re: need help reading piston burn pattern
So your head gasket was leaking it looks like!
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Re: need help reading piston burn pattern
Rizzle wrote:Just to clarify, when you say fatter you mean a thicker needle like mrriggs suggest, correct? Not a fatter fuel curve, as is normally meant with the word fatter?bladefrost wrote:Tested my bike this afternoon after fixing the cylinder gasket leak and putting a fatter needle and it has improved a lot. Almost eliminated the stalling when quickly accelerating. Thanks to mrrigs for the advice. Afterall this is just a tuning issue. The ignition switch is just okay. Gonna find another needle that is yet still fatter.
fatter or thicker neeedle i mean. it wants leaner mid range. the boowaaah sound followed by misfires i though was lean but in fact was rich. is that right?
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Re: need help reading piston burn pattern
mag2555 wrote:So your head gasket was leaking it looks like!
yes its leaking. now i fixed it and power went back with also the help of the thicker needle diameter and straighter taper. bike now sounds crisper than before but still lacking
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Re: need help reading piston burn pattern
You still have not done a air pressure test to check for intake or exhaust valve leaks yet right?
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Re: need help reading piston burn pattern
mag2555 wrote:You still have not done a air pressure test to check for intake or exhaust valve leaks yet right?
not yet. i use only solvent. i put it in the intake port and exhaust port and see if there is any hint of wetness on the valve faces. what concerns me is there is oil in the piston heads. no smoke on the tail pipe. but the tail pipe has wet carbon in it. exhaust port is black and dry, not grey. only the exhaust pipe is wet and black
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Re: need help reading piston burn pattern
Confirmed the idle issue is fixed. I just changed to another carb. Maybe i got a lemon carb, this pwk knock off just wouldnt run right.
Re: need help reading piston burn pattern
Oil in the chamber is not good, even if you found the other issues. Leakdown check would let you know if your rings are sealing. Valve guides would be worth checking too.
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Re: need help reading piston burn pattern
Is it oil, or does it smell like unburned fuel?
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Re: need help reading piston burn pattern
Didnt bother to smell it.. no white smoke on the tail pipe. Also the pipe is wet and blackmag2555 wrote:Is it oil, or does it smell like unburned fuel?
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Re: need help reading piston burn pattern
Guides are good. There is a light scratch on the bore and pistonCalypso wrote:Oil in the chamber is not good, even if you found the other issues. Leakdown check would let you know if your rings are sealing. Valve guides would be worth checking too.
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Re: need help reading piston burn pattern
Maybe i just need a very good carburetor. This thing is difficult to dial in. It bogs and stalls mostly when quickly accelerating under load. But if you slowly roll on the throttle it doesnt stall and will reach top speed only takes longer
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Re: need help reading piston burn pattern
There is no way to adapt a Carb to those motors that have a accelerator pump for God`s sake?
Also, do you still see fuel backing out of the Carb when you apply the throttle?
Also, do you still see fuel backing out of the Carb when you apply the throttle?
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Re: need help reading piston burn pattern
There is the keihin fcr 28mm pumper but its too damn expensive. I see fuel is minimized backing out on the carbs mouth but its still there and i often see this on other fast bikes too fuel mist coming out when they are revving. Maybe its their cam's overlap causing this?mag2555 wrote:There is no way to adapt a Carb to those motors that have a accelerator pump for God`s sake?
Also, do you still see fuel backing out of the Carb when you apply the throttle?