slow as a snake
slow as a snake
I have bought a 2002 fat boy with straight vance and hines pipes with a 1 and one half baffle and a k&n air filter. The bike is carberated and the exhaust is sooty. Backfires on letoff all the way to idle. I do not know of any other modifications. It has the stock ecu. It does not have much power. Any suggestions?
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I have bought a 2002 fat boy with straight vance and hines pipes with a 1 and one half baffle and a k&n air filter. The bike is carberated and the exhaust is sooty. Backfires on letoff all the way to idle. I do not know of any other modifications. It has the stock ecu. It does not have much power. Any suggestions?
Pull the bowl off the carb, and let's see what you have for jetting, for starters.
Scott
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From: North Florida
You could not ask for a worse combination for making power than drag pipes with baffles because there is no expansion chamber and the baffles are a bandage fix for too loud of pipes and they just choke off the exhaust making the bike run rich.
Bigger pipes like two inch help, but then you lose all low end torque.
If your exhaust is sooty then that means it is running rich, check your jetting it should be 45-190 stock, it was probably rejected with the pipes then the baffles added to try and quiet it and made it too rich.
I would recommend 48-190 as a start.
Crackling on decelerating is usually caused by an exhaust leak, they probably did not change the gasket when they put the new pipes on and it is sucking in air, when you let off the gas.
Try pulling out the baffles or at least some of then and see how it runs first, then check the jetting and change the exhaust gaskets.
Oh yea how many miles on the bike, it might just be tired.
Bigger pipes like two inch help, but then you lose all low end torque.
If your exhaust is sooty then that means it is running rich, check your jetting it should be 45-190 stock, it was probably rejected with the pipes then the baffles added to try and quiet it and made it too rich.
I would recommend 48-190 as a start.
Crackling on decelerating is usually caused by an exhaust leak, they probably did not change the gasket when they put the new pipes on and it is sucking in air, when you let off the gas.
Try pulling out the baffles or at least some of then and see how it runs first, then check the jetting and change the exhaust gaskets.
Oh yea how many miles on the bike, it might just be tired.
Last edited by Harleycruiser; Nov 14, 2012 at 07:50 AM.
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