BK mod jetting?

Thanks to all the great information on this site I just completed the BK mod on my 2000 WR400. Just got the WR a fiew months ago, got a great deal and decided to try the 4 stroke. I ride in northern Michigan with my 14 yr old son, exclusively single track. My previous bike was a CR250 and I have allways felt 2 stroke was the way to go. 4 strokes rule, the more I ride it the better I like it, smooth and totally maintenance free. My only complaint with the bike is that is sluggish in the middle, to wheelie over the whoops I have to open the throttle all the way. Hopefully the BK mod will correct this. The jetting is 170 main,OBDRS jet needle on 3rd clip and 42 pilot, pilot screw 1 1/2. I ride at approx. 800 feet. Thanks for all the great info on this site. I feel pretty confident working on 2 strokes, looked at the WR carb and was very intimidated, stuff all over the place. TT site had all the information to get me up to speed.

I also had weak middle until I changed to YZ's EJP needle. Now I'm wheeling in 5th.

Is it YZ timed??

No it is WR timed. Have thought about YZ timing but holding off for now. Will YZ timing create reliability issues that I don't have now?

Doesn't with the YZ's............

Dodger :):D

Get your hands on an OBEKN needle and set it on clip #3....You won't be sorry.

Bonzai :)

Called the local Yamaha dealer and they can't find part # for the OBEKN needle, what bike and year would they need to search to find it? Or how would I find one.

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