426 Big Bore Info, please

Im not sure if I should start up a new thread on this, so I figured I'd start here. Looked up 426 stroker and BB and couldnt really find any info on TT more recent than '05. I have an '00 426 and I would like to know if there are any current manufacturers that make a BB kit and/or Stroker kit for this bike. Not looking to go too crazy, I'd just like to get more power out of it. I ride supermoto tracks mostly. I was also wondering what the best pipe for this bike would be? Ill look that up though. I have the '05 450 titanium exhaust currently. Any help would be much appreciated. Thanks.

I put a Thunder Alley system on my 01 XR 400 and it worked out great. Passed sound check, had a spark arrestor, looked good, tough as nails, and cost me only 350 installed. I'm rebuilding my 01 YZ426F as we speak and plan on installing another Thunder Alley system. For the money, I don't think you can bet it.

I think you'll find the TA system much louder on a YZF. An XR400 will almost pass a sound check without a muffler.

Thanks a lot guys for all of the input. Price on a pipe really isn't a factor (as long as I get a good deal!! LOL) I am looking to improve the bottom end, sound is not even a consideration as I ride mostly track (unless there are restrictions that I don't know about when racing), planning on installing both int. and exh. hot cams stage 1, and stroking the the engine. I would like to eventually start doing some local race series'. With that in mind what would your suggestions be? Would like to do it right the first time. Thanks again and Im going to keep searching existing threads and learn!!

Get some suspension work done. I don't know where you like in Cali but I live near the old MDK shop that is now called Blonix. Same guys from MDK just diffrent company name now. They have a highly reputable name, and their work speaks for them.

I went with a pro circuit T-4 system on my 426. I loved it. I had a little issue of it fitting right though. The welded on bold on the exhaust would hit the subframe. I had to make a few mods to the bike. As far as performance goes I liked it better than the FMF pipe I had on it. The T-4 makes the bike bark pretty hard and ever better with no sparky in it.

Only parts I don't like about the 426 was that the frame felt to flexible to me when taking on larger jumps, and suspension (Stock) was to soft for me when taking on jumps (165wt.). Also with handling, in some lines it can be more difficult to get that 426 to really stick into the turn and ride it out clean, it can be a little unpredictable. (Thats the reason for suspension work).

All in all, I love the bike. Good amount of power. Bullet proof if you maintain it well. Lots of fun the play on.

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