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Backfiring out left cyl.


Wallrat

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See my sig. for mods. My left pipe is backfiring like crazy and is way hotter than my right. In addition, it feels like I'm only running on one cylinder. Bogs like crazy especially when I give it some gas. At idle it seems to run okay except for the constant backfiring and being somewhat difficult to start. I just got back from glamis so I haven't been able to do a full diagnostic on it yet so compression is still an unknown. I cleaned my left carb and re-sync'd em. Plugs look the same, both slightly rich. My silicone exhaust coupler is falling apart so I'll be ordering a new set but in the meantime I'm 99% sure I got it to seal by moving it over a tad and reclamping it. Without knowing the compression right now I'm thinking maybe an air leak? You guys have any other ideas? All this started last weekend after a run up China Wall it started running like it was rich. My temp was hot (about 200 degrees) which is normally where I shut her down. I let her cool off and changed the plugs and that helped me get back to camp running somewhat normal. My air filter was pretty dirty so I figured that was the cause for the rich condition.

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The very same thing my bike did a while back, except it was my right cylinder. I fried the piston. Left side had 120psi, right had 40psi. Right pipe got HOT immediately. I melted the piston due to an air leak (blown head gasket).

 

Do a compression test. Might be time for a fresh top end.

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  Without knowing the compression right now I'm thinking maybe an air leak?  You guys have any other ideas? 

 

I think it's definately an airleak, should be easy to find.

Check the carb boots and clamps, especially in the area of the crossover tube or boost bottle if you have one.

Other places to check would be carb tops, choke tube, reed cage gaskets etc.

 

If not an airleak, possibly a damaged reed?

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It was definately time for a rebuild but I WAS gonna wait until after Turkey Day. Turns out of got 120 psi on the right, and a big fat zero on the left. I took a look down the plug hole with a mirror and the top of the piston looked normal. Oh well...at least I've got a couple weeks to get it done. I'm just hoping the damage inside isn't too bad.

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It was definately time for a rebuild but I WAS gonna wait until after Turkey Day.  Turns out of got 120 psi on the right, and a big fat zero on the left.  I took a look down the plug hole with a mirror and the top of the piston looked normal.  Oh well...at least I've got a couple weeks to get it done.  I'm just hoping the damage inside isn't too bad.

281000[/snapback]

 

 

it can't be as bad as mine, at least i hope not for your sake

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Looks like the ring caught on the exhaust port. The top of the piston is missing a piece, one ring is in 3 pieces and fell off in my hands, the other ring is nowhere to be found, head is nicked to hell...

 

So what do you think the odds are that the missing ring got expelled out the exhaust? Time to split the cases...thank god for beer!

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Looks like the ring caught on the exhaust port.  The top of the piston is missing a piece, one ring is in 3 pieces and fell off in my hands, the other ring is nowhere to be found, head is nicked to hell...

 

So what do you think the odds are that the missing ring got expelled out the exhaust?  Time to split the cases...thank god for beer!

281116[/snapback]

 

 

 

Aw Shit! You were a busy dude yesterday...

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