My 07 has about 30hrs on it and I've read that an 05R cam should provide a good overall boost in the powerband. Bike has JD Jetting, trimmed air box w/Twin Air filter, cut exhaust baffle, 13/51 gearing and runs good.

Ron Eyers shows two part numbers, two prices 670 being about $5 more:
14100 KRN 670
14100 KRN 730

Which one should I order?
Is there anything else I should replace when I install this cam…like valve springs, retainers, cam buckets? Any other advice?

Thanks for your help.

The 14100 KRN 670 is the 04 and 06 grind cam.
The 14100 KRN 730 is the 05 grind
The 04, 06 cams are hotter on the top end and lose a little on the low end when compared to the X cam.
The 05 cam gives a boost through the whole range but not as much top end as the 04 and 06 cams.
Another good choice for the X is a Stage 1 HotCam. Awesome boost in low and mid range with out any loss on top.
Basicaly it all boils down to what type of riding you do and where you are wanting more power .
As for replacing springs and such, any of the cams mentioned above are straight drop in cams.
you would only need to replace any parts that show wear.
Hope this helps.

Edited by keviwa, 17 July 2012 - 02:02 PM.

Thanks for the info Kev!

Has anyone compared a 05r cam to a HC1 cam on a basically stock (JD jet, airbox mod, cut baffle) 250x?

The bulk of my riding is 2nd & 3rd gear single track with a few laps around the mx track.

Yeah several people have tested them via dynos and seat of the pants. I can tell you that The 05 R cam will definatly give you more top end compared to the HC 1 cam. I have the HC1 and it is all low to mid boost. I ride the tight stuff and needed the low-mid boost more than I needed top end. The 05 cam gives a small boost in the low end but not as much as the HC1 does. You cant realy go wrong with either cam as they are both better than the stock X cam.   Kevin

I have a 06 250x done the CCC mod, rejetted the carb and added a FMF slipon, changed the gearing. The bike is fun but still a slug, slow reving. I was leaning towards the hotcam stage 2. But ended up ordering the 05 R cam just now. Hope it livens the bike up!

You will love the r cam if your looking for more boost. Remember to do the pink wire mod to get the most out of the cam.

Already done it!