2002 650 won't go over 25 mph
 

Have checked out and I believe it has a flat cam on the front cylinder. Has anyone had this happen? I checked the belt and clutches and cleaned the carbs. Set the valve clearances and noticed that the rockers on the front cylinder don't move as far as the rear ones. Thanks, TORK.

Yes, flat cam sounds like a good guess. I've seen that before, especially on quads that's used for lots of slow speed riging for looooong time like in farm or ranch work. Not enough rpm, not enough oil circulation, high temp - a perfect recipe for flat cam.

does it feel like a rev limiter is there at like 25-30mph? My buddy has a Prairie 360 and its cutting out and will not go any faster, starts fine, runs fine, until half throttle and will not go any faster

There are two rev-limit mode on the 650 and 360 (and all other Kawi KVF quads):
1. WOT rev-limit comes in at 7000 rpm and you would be flying at about 55+ mph in HI gear on flat.
2. Belt Failure rev-limit comes in at about 2500 rpm and you would be going only at about 5 to 7 mph at the most.

There is no rev-limit that allows the vehicle speed to 25-30 mph.

Your buddy's 360 has other problem, possibly carburetion or other mechanical.

thats what im asking you, is that what a flat cam feels like? feels like its cutting out LIKE a rev limiter would do just at a diff speed, bout 25-30. If it was the carb i wouldnt think it would start and run fine up to that point, or there would be a flat spot and be able to push thro on the throttle and feel something different, it would die all together, stall, or starve for more air/gas. But his kawi 360 just wont go over a certain speed/rpm, let off before that point and runs fine

This one doesn't miss, it just acts like that is all it has. I have another one in here that is not running right also. It is Arctic Cat 650 and it had terrible bad fuel in it. We cleaned the carbs a couple times and it will start and idle good but is very sluggish and no top end. It will pop back through both carbs, valves are ok, acts lean but can't seem to find the problem. Good fuel flow to the carbs and have ran sea-foam through unit.

i have an 02 prairie 650 doing the same thing, did you ever find the problem? i have cleaned the carbs three times and new spark plugs. it spits back out of the front carb the most and has no power

Sorry I have not checked back in. I have not found out anymore on this problem. It is one of those that really eat at you. Mine will backfire out of both carbs but the front one does seem to do it more. I need to check timing but don't think that is the problem. If I put the choke on a little it will run better but still not well. I really think it is a fuel problem but can not figure out where I am going wrong. TORK.

I have this same exact problem with a 2002 prairie 400 it runs great starts and idles great but just seems like all it has is about 23 mph. It is stumping me. I went through the carb and it is clean the belt looks good the compression is about 100 psi. Im not sure what the specs are though for this quad because for the life of me I cannot find a service manual to download on the internet. Any ideas??????? anything at all? or any help with specs such as valve clearances, compression, and belt specs would be greatly appreciated

thanks

Put unit back together today and it runs great. I have never had a set of carbs this hard to get clean. Ran them though a sonic cleaner a dozen times before it would run right. So glad to get this done and out of the way! TORK.