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'Bird puts out "smoke" but not regularly?


Zero Knievel

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Okay, I've heard this more than once from someone behind me.

Smoke came out of my exhaust. Never are they clear as to what I was doing when it happened.

I have a K&N filter, but no modification to the ECM. I was tempted to install a stock air filter and see if that changes anything. I do have soot on the exhaust.

I suspect these bursts of smoke may happen if I power downshift (drop down a gear with high RPMs).

I'm suspecting the fuel balance is off, but I'm wondering what else to watch for.

FWIW, 53,000+ on the odometer.

Also, the battery is dying, need a new one, but it may have been going for the last year (slowing loosing power) which is about the same time frame I've heard the comments about "smoke" coming out of the exhaust on occasion.

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The color of the smoke would be helpful...

Blue - generally means oil (rings, valve guides/seals)

White - generally means raw unburned fuel, and/or possibly coolant (FPR - fuel pressure regulator on FI motors, possible head gasket issues)

Black - generally means heavy carbon content (too rich fuel mixture, stuck float on carbed bike, compromised diaphragm FPR on a FI bike)

With mileage in excess of 50K, some minor puffs of smoke (intermittently upon acceleration/deceleration) may be within normal expectations. A leak down test and a compression test may help narrow down the issue(s).

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No idea on color, but I think someone might have commented if they thought it was oil.

Given the soot on the exhaust, I'd say black.

I'm doing a coolant change soon, so that would tell me if there was a coolant leak.

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Sounds good.

I'll do a compression check when I get around to accessing the airbox for the filter change, but I'm hoping going back to a stock paper filter will solve the "rich" problem. I suspect the cost and trouble of an aftermarket ECM just to use a K&N isn't worth it.

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You are correct.

The Aftermarket ECM will NOT correct the Smoke Puff.

The stock air cleaner is better than the K&N as far as the Bird goes, and here's why, because it miantians the smouth flow of air in the air box and down through the throttle bodies above 9K rpm. The K&N does not.

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Normal.

Yes on hard excells and shifts... a little puff of the super rich.

A coolant leak would be white smoke.

Yeah, normal if you've ridden behind EVLXX.... I have my bike set a bit rich too. but not to the point of heavy soot buildup on the can.

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