white bros exhuast

ok just fitted a white bros short exhaust with a highboy header pipe

how many disc's should i have in the spark arrester or shud i run it straight thro?

Hi, I have the exact same system you just bought, however my bike is fully dismanteled and will not be up and running until March. ( I xc-ski in the winter )The person I bought the pipe off of as well as the tech. info. booklet that comes with it confirms that 4 discs is as stock. ( like 1 dia. opening ) I will attempt to run either 6 or 7 to open it up a bit and will probably have to jet slightly richer. Let me know what you find on your end ( or other side of the pond as we refer to Europe ) :) Take care, good luck!

[This message has been edited by Hugh LePage (edited 01-17-2001).]

[This message has been edited by Hugh LePage (edited 01-17-2001).]


I have the same set up and I run mine wide open, no disks at all.

if you need to run a SA then thats a different story, but if you are in a mx situation remove all disks and just bolt on the end cap.

Hold it Wide

Smitty http://www.fastbydesign.com

I have the Eseries on my 99400 and love it.

I actually bought the Noleen complete setup first. Tapered header and silencer. But I race hare scrambles and needed a spark arrestor and they don't make one for the Noleen.

So I bought the Eseries pipe and it matched right up with the Noleen header.

My friend has a yz250 that he piped FMF the same day I changed to the White Bros and he was keeping up with me all the way thru.......This pissed me off cuz no 250 shud even come close to hangin' with the 400 in the open.!!!

So I went to the dealer on the way home and picked up a pack of discs and jetted the bike taller and guess what......

The next week I had my top end back.

I think I have either 12 or 14 discs on it and it runs like a raped ape. I did jet it very tall thinking it would also give more top end and it helped after i fgured out how tall to go w/o killing the bottom end completely.

WhiteBros. actually say that their pipe runs with less HP if you pull the end caps regardless of how much faster it SOUNDS!!!!

I have seen dyno charts on it and at least that is what they reveal also.

so try more discs and maybe jet a little taller.




ride BLUE


as far as top end goes this is what white bros says:

"The High-Boy headpipe literally mirror images the stock powerband, but has slightly more top-end power,

since the headpipe is shorter. Like the Tapered headpipe, it too carburates & feels stronger in real riding

conditions (that don’t show up on the dyno). Most importantly, it clears the oil filter housing so that the oil

filter may be removed without removing the exhaust pipe (the Tapered headpipe also has this feature)."

and when i received my e-series shorty it said in the documentation that if a SA was not necessary run it without disks, as this makes the most power.

Good luck

Smitty http://www.fastbydesign.com

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