i have to replace two of the sensors on the 02 and 06 model i have. Thats what ussaully takes car of the problem. the speed sensor will give you problems too if if wont go into reverse. you can try them and it will take care of your problem.
06 yfz cam mod, carb mod, kicker setup, jd performance +3 arms, fox lt float evols, +4 lsr axle, protaper bars, hep battery box, oversize aluminum oil tank, laker plastics
05 450R itp ss rims, stage two hot cam, jetted, Yosh pipe, gtt link
05 450R, big bore, Duncan cam, full rossier pipe, +2 Houser arms,+2 houser antivibe stem, Pro taper bars, +2 G force axle
06 Rancher Stock
07 420 Rancher
07 Rubicon jetted, KN air filter,baffle removed,homemade front and rear bumpers. ITP rims and tires