Got a 01 DS650 my question is is it safe to run up to the rev limiter? or is this pushing the motor to the limit would rather not take a chance on hurting the motor

 

No worries, even without a rev limiter, you can't rev high enough on stock cams to hurt the motor.

 

Lyrch is correct for the most part. With the wheels on the ground and the ATV in gear it is fairly safe to assume you can't rev it too high. However, if you crash, or rev it too high out of gear parked (could also be from a crash etc.) then your engine could tear itself apart. If you get the RWR CDI without rev limiter, then get a tethered kill switch - this will help. Otherwise, you can get one of a few CDI boxes that have raised rev limits which are perfect for most people. If you plan to 'go big' eventually, you should consider the Vortex or MSD CDI boxes which are both programable and are still good for recreation riders. (I know the Vortex is OK for recreation, I dunno if the MSD requires extra work or anything, haven't heard a lot about it.)