If you have the problem of the 03 650KVF (Prairie) jumping out of high gear on the fly, but no problem with either low or reverse gear selection positions, please be advised that the adjustment of the shifter lingage is the most likely cause. (See the Nyroc or Kisssofdeath site for the tech tips there on the shifter linkage adjustment instructions, they are very good and very clear) My ride began jumping out of high gear on the fly, after only 650 miles of use. (OUCH!). The correction that I found worked was to increase the effective length of the shifter link rod by two full turns, but every quad is different, so you will need to make this adjustment according to your own machine's quirks. Also, I have slightly modified the shifter detent rack (located immediately under the shift lever ****) by using a 1/4 inch diameter round file to make a small (1/10th inch deep) concavity on the flat detent surface of the rack, right behind where the shift lever rests in the selected gear position. You must do this for each gear position to preserve symmetry. This concavity in the detent will then act to hold the shift lever in its set position when under the rearward-acting feedback forces coming from the tranny under heavy acceleration or when on really bumpy trails. Of course, you must make each concavity the same depth (and not too deep) and then re-adjust the effective length of the shifter link rod so as to reset the transmission engagement position afterwards. This detent-rack mod really worked for me. It takes about an hour to do this and the shifter-rod re-adjustment. Note also to check and tighten the front engine mounting bolt (14mm) which is a common problem contributing to shifter problems. (You will have to remove the engine skid plate (remove 4 10mm bolts) to get at it, however. Add another 1/2 hour for that.) My thanks to Kisssofdeath and Nyroc for their helpful advice and excellent website technical information. (http://atv.dnsalias.com is Nyroc's website)