my valves on my 01 tuliped and caused the valve clearance to tighten.
check the intake side.

 

i cut and pasted this from another thread Raptor Tech Bullentins(by Knowsalot) I noticed that the Bullentin talks about the 2001 choke cable take a look i cut and pasted the whole thing.


There were more than I thought, but most were just tips for mechanics and nothing more. There were a couple that I thought I would post. These were the only ones of any importance. This is going to be looooooooooong.

Air Filter Guide Improvement...'01 and '02 Models
This bulletin makes it harder to misalign the air filter base where it meets the airbox....Part Number 5LP-14458-01-00

Reverse Indicator Light Flashes...'02 Model Only
The 2002 Grizzly 660 and 660R Raptor have a speed sensor self-diagnostic feature. If the engine is operated at 3000RPM or higher for 10 seconds but the CDI does not receive the signal, the reverse light will flash in one second intervals. This will most likely occur if someone revs the engine in Neutral or Park[On the Grizzly].

To reset the system, simply turn the key to the OFF position. Verify the speed sensor operation:
[1]Turn the key OFF to reset the circuit.
[2]Ride the ATV above 3000RPM in any forward gear for at least 10 seconds. If the light does not flash and the speedometer[Grizzly] functions, the system is working correctly.
[3]Check the speed sensor wires for chaffing or rubbing, which may cause an intermittent short.

Parking Brake Switch Operation...'01 and '02 Models
The 2001 and 2002 YFM660R Raptor is equipped with a parking brake circuit which limits engine speed to 2300RPM anytime the parking brake is activated. Because this condition can sound like an ignition misfire, you should be aware of the normal operation to avoid unnecessary troubleshooting.

Choke Cable Improvement...'01 Model Only
Choke Cable Improvement...'01 Model Only
Some customer report that the choke is stuck in the ON or OFF position. Water from pressure washing can enter the top of the choke cable and drain into the choke plunger of the carburetor. This can cause the choke plunger to corrode within the carburetor body.

To prevent this from happening, a new choke cable was developed. It features a shrink tube on the cable wire and a sealing ring to block out water....Part Number 5LP-26331-10-00


Correct Installation of the Output Shaft Collar..'01 and '02
If the output shaft collar is removed, be sure to re-install it with the notches facing inward. If the collar is installed incorrectly, the oil supply to the transmision output shaft will be cut off causing major damage to the transmission.
[This is behind the plate that is bolted to the engine with two bolts, BEHIND the front sprocket]

Thats pretty much the only bulletins of any importance that I found. The first bulletin I mentioned here was in my own words because everyone knows about that one now. The others are quoted directly out of the Bulletins.

Original post KNOWSALOT

Archer

 

Thanks alot all, we pulled the chock plunger out of the carb tonight, and it was all gumed up and rusty spring. We cleaned it up and WD-40'd it and it seems to be running better, at least at idle. We'll find out today. Thanks for all the ideas and where to start!! I'm going to be posting another on about the front shocks, so thanks a lot all!!

 

We also found another problem, other than the front shocks being blown from another post I put in, the rear bearing in the rear housing are shot. That I know is covered under the warrenty. Has anyone installed a different set of bearings or different carrier with a grease fitting? Thanks again guys, even though I have a Polaris! You have all been very helpful for me and my friend.