[ninjaryda]

I don't think this bike has a rev limiter. If it is running out of power at the top I have a feeling you are over revving the motor. You may get some gains from your flow upgrades, but don't expect a huge power increase. It is still a 250 after all.

Yeah, what was there - wasn't a huge difference to begin with. But I did want to get it back. I read on some ninja wiki that the original 250s had a rev limiter at 15k, then dropped this down to 14k starting with 2005 models (if I remember right). It definitely felt like a rev limiter when I hit 14k before (one spark plug is cut out), where as now at 13.1k - it just breaks up slightly (like not enough fuel, which makes sense given the new change in the valve overlap and not letting the headers scavenge enough in the cylinder to pull in more fuel/air mixture).

Are any top end gains from the tighter valve clearances worth the extra maintenance?

If it means I have to check it every 2-3k miles, then that's fine with me (it wasn't that bad). Although I'm gonna try a few other options first.

I've read on this board that changing to pod filters really sucks. The air box does a pretty good job of stabilizing the air flow into the carburetor. You may end up rejetting and rejetting and never find a good setting because of the inconsistency of the air flow around the pods.

I've read this too. Which why I was kinda of reluctant to do this. But Pod filters (or maybe dual K&N filters) are cheap enough. I could always revert back if I need to.

I kinda wish this engine had hydraulic lifters for the cam. There was cheat/trick you could do on car engines where if you ran a large overlap (which normally killed your low end because of the rapid bleed off at lower RPMs), you could use rapid bleed down lifters. Which effectively gave you a dynamic cam profile. The lower RPMs would cause the lifter to bleed out faster and thus close the overlap some. And at high RPM's, they wouldn't so you'd get the full overlap of the cam profile. Oh well :/