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Another YZ timing change question

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I searched the archives for this and I think I know the answer, but I'm not sure and need a little advice. I've changed my 99 WR's timing to YZ (rotated exhaust cam one tooth clockwise) and now my bike runs like crap. It seems to be too lean on the bottom now and stumbles badly mid-range. Here's my question (a Yes or No will suffice): Is it a given that carb adjustments (needle and pilot jet changes at least) will need to be made when doing the timing change? I was just wondering if I messed something up or is more work required? If this helps, I ride near sea level, slow jet- #45, main- #180, #DTM needle 4th clip, #100 Pilot air jet- these worked fine with WR timing. Thanks

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If your running a YZ or aftermarket pipe, use the jetting in my signature. My bike pulls like a tractor, blows thru the mid range, barks on the top, starts first or second kick and NEVER fouls plugs.

Oh and I've also de-octopussed and used the jets that Clark outlined in the tech section.

You won't be disappointed :)



99 WR400f, YZ timed, MX-Tech suspension, Scotts steering damper, White Bros E-Series (12 discs), tapered header and a/f. Kouba T-handle for the fuel screw. Works Connection billet throttle tube and frame guards. Cycra Pro-Bend, triple clamp mount handguards. Thumper Racing rad guards , Renthal Jimmy Button highs, YZ Tank and IMS seat, YZ number plate, odo removed, EKP #4, 50PJ, 175MJ at 500-1000' Thanks James Dean!

[This message has been edited by Bill (edited 08-15-2001).]

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