I just put the Curtis Sparks full exhaust on my YFZ 450.The main is a 170, the needle is on #5,did the cam mod.Befor I put pipe on I never hit the rev limiter,now I hit it in every gear [img]i/expressions/face-icon-small-disgusted.gif[/img]Did I miss something or is this what the pipe mod dose????[img]i/expressions/face-icon-small-confused.gif[/img]The power is unreal,but that rev limiter,if it is the rev limiter,has got to go!! [img]i/expressions/face-icon-small-mad.gif[/img]

 

Anybody have an idea,[img]i/expressions/face-icon-small-frown.gif[/img]I don't have a clue.......and that would be an under statment. [img]i/expressions/face-icon-small-happy.gif[/img]

 

When you look at most of the dyno graphs you see that the power starts to fall a ways before the redline and its not too bad before the peak either. You have a pretty good area to work with. Just shift earlier.

 

Okay my Z400 does the same with the Rev limiter. I lowered the front sprocket 1 tooth. My question is, is it real bad to hit the rev limiter? Mine does it in every gear too.

 

The rev limiter is there to prevent you from over revving the engine.I hit mine befor on the starting line of a drag race,thought nothing of it. But it seems I hit it now when I shouldn't be. [img]i/expressions/face-icon-small-sad.gif[/img]

 

Just buy an aftermarket CDI box with no rev limit. (if they make one for it yet)

 

The aftermarket pipe allows the quick-reving YFZ to rev even faster, because of the freer flow vs. stock pipe. This happens on a alot of quads with aftermarket pipe. You may have been hitting the limiter in stock trim too, it is just less pronounced with the stock pipe, so you don't pay attention to it. The most important thing to do is to determine that your bike is still achieveing the appropriate RPMS before hitting the limiter. If not, it could be an air intake issue also.

 

Thank's PredFan.[img]i/expressions/face-icon-small-wink.gif[/img]I guess I'll be needing an aftermarket cdi box,when they hit the market.