Hey everyone. New to the forums. Glad to be here.

I have a question regarding my 2003 Yamaha Grizzly 660. I've only had it about a month and its my first fourwheeler.

It has 3900kms on it, very well looked after.

I took it on some mud trips, and i do do some WOT road running. Lately its starting to run really "boggy" .. like mash the throttle and it dogs and kinda sputters a bit and then eventually will get going, but has terrible throttle response lately. I keep it clean after mudding and regularly check my oil and air filter. Although when i checked the oil today after it began to run boggy it was REALLY low. Topped it up and checked the air filter everything seems ok..

Any ideas??