I wouldn't have thought exhaust end-can packing would significantly increase power output, or reduce back-pressure. That is normally dealt with by the tuned length of the pipe itself and overall diameter of the exhaust-can internals. Removing the packing will obviously make it noisier, reduce any heat build-up and possible reduce the weight, but only a little. Other than that I don't think there will be much in the way of performance enhancements to be gained. If you however remove the internal pipe work inside the exhaust-can and install a straight-through internal pipe, with custom packaging I would have thought this would give more impressive power gains. The first area for exhaust modifications on a modern bike should really be at the Catalyst end. This device reduces power output, increases weight and heat.
It will gain about 2 to 3 horsepower when jetted
How many horsepower is a 1200 Yamaha Waverunner horsepower rated at
How much horsepower does a stock 2006 Yamaha raptor have?"
An 80cc Yamaha raptor typically has 3.5 horsepower
The Yamaha VStar 250 has about 21 horsepower. The Honda Rebel has about 17.
5 horsepower belive it or not
about 13 horsepower at the wheel
The Yamaha bravo is 18 horsepower.
21 horsepower
45.6 horsepower
One million horsepower!
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