WR/WB e-series-s-bend tuning


I have a 98WR400 and live in Arizona @ around 1200ft altitude. I have been tuning in my e-series, s-bend pipe for a couple of months now. White Brothers suggested starting with 9-12 plates for best all around performance. I have found that with YZ timing, 2 1/2 turns on fuel screw, 48 pilot, 175-180 main, 12 plates works great, a bit loud though. Tried the quiet cone insert and the db's dropped drastically, but it was like giving the low end a shot of Novocain, mid-high was pretty much unchanged (removed it by next ride). Installed the tapered head pipe and low end throttle response suffered, but all around power greatly improved. The final fix was to go to 16 plates, sounds like too many and yes loud, but with out any question this is the best power band you can get with this pipe.

I have a stock YZ needle on order, but not sure if I want to change anything at this point.

Good Luck


Forgot to post final results: Major low end throttle reponce gain that was lost from YZ timing change, black soot gone, smooth power increase accross all rpm's (no step in power band), starts first kick hot or cold.


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