My 03 grizz has approx. 650 miles on it. When I accelerate from stop to full speed, it wants to hesitate several times like its being bogged down. Had the valves adjusted already just in case someone asks. Belt case is dry. I do have 27 inch bearclaws on it. I havn't looked at the belt yet. Any experience with this problem shared with me would be greatly appreciated.

 

You may have water in tank, my did this once and I drained the tank and put new gas in it and it stopped. If it spits and sputters as you try to reach the maximum speed then this may be your problem.

 

Could be a carb problem, you changed the gear ratio with the bigger tires, it might need more fuel in the midrange

 

Mine did that when it was too rich. I rejetted to rich in purpose and then backed up one jet. I would make sure that the air filter isn't pluged up. Also, Check the plug after running it at WOT for a little while. If it is wet or dark brown then you have a problem getting air.

 

When you had the valves adjusted, how were they. Were you having problems before you had them adjusted?

 

Could be a slight vapor lock on the tank. Does it hesitate all of the time under the same conditions? If so, come to a complete stop, unscrew the gas cap to let the tank breathe, then try it again after you screw the cap back on.