WR400 Main Jet and Rev Limiter

I eliminated my exhaust baffle, air intake top, cut throttle limiter to allow full throttle, moved the needle valve clip to 4th position, and the bike ran like a scalded dog. It did cut out at high RPM. I replaced the 165 main jet with a 180 and it seems to have more power but when it gets up to top RPMs it seems to be limited. Does the WR400 have a REV limiter? ...or am I starved for fuel at high RPMs at full throttle and therefore do I need a larger MJ. The bike has great power at full throttle until it reaches the high RPM threshhold. Effortless wheelies in 3 gears. Thanks for your help. Ron

[This message has been edited by RonC (edited 02-12-2001).]

You may very well be right, it may be a jetting issue.

I thought I'd throw out the idea that it may be caused by a throttle stop that has been cut down to far. By that I mean, if you didn't check the throttle valve clearance after you cut the stop, you may have cut off too much allowing the valve to open too far. Thus causing your engine to cut out up top.

Probably no the case here, but I've seen it happen twice. Both times they cut off the recommended amount and it ended up being too much...


JJ - 99 WR; WR timed, EKN Needle, Scotts stabalizer, Scotts triple clamps, Pro-Tapers, Michelin S-12's, Terry Cable hot start, MSR Raptor clutch lever, Moose skid plate, Works frame guards, Acerbis Pro Rally guards, Renthal MD-soft grips, Factory Effex graphics, YZ IMS seat base, YZ Factory Effex seat foam and gripper seat cover, YZ rear fender

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