E-Series/ S-bend setup

I have a bunch of stuff from White Bros that is pretty interesting. They say that you actually LOSE power with the straight through end cap on. They say it's better to run with lots of disks. It's because of the back pressure the blocked end creates, the resonense that back pressure produces and how it 'sucks' the gases out of the exhaust valve after the next fire of the plug. I'll have to post it so you can see for yourself (if I can find it).


Thanks Bryan! I will put the discs back in. I would appreciate any additional info on the subject that you might have. Tomorrow is the first enduro of the year and unfortunately I have not had enogh time to test...Man I'm already getting butterflies... :)

I was just working on my E-series and was able to mount the endcap only...this allows the exhaust to flow straight out the back instead of forcing the exhaust out the sides and thru the plates. I know this removes the spark arrestor from the pipe but my riding is all on private property so this is not a problem. With the plates removed it reminds me of a 2 stroke silencer with its straight thru flow and packing on the outside.Is anyone running this set-up? On an earlier post someone said that a baffle kit was necessary from White Bros. Is this necessary to get back pressure for torque and/or sound levels? Don't some of these other exhaust such as power core IV have the straight thru design?


2000 Yamaha WR400F

1988 Honda NT650 Hawk

1977 Suzuki RM250B

1974 Honda XR75K1

My YZ'ed WR likes at least 15 disks and you can tell the difference. This weekend I went riding in the National forest and went to 10 disks to quiet things down a little and I was suprised at the loss in top end power.


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