My buddy has a 2003 Raptor 660, it has had only 6 tanks of gas put through it. He's been complaining about losing power in 3rd gear. We did a compression test and found 95 pounds of compression. The book says it should have 180. We have not taken the motor apart to see what the issue is yet. But I'm looking for some opinions on what he did to cause this with such little time on the motor. He is rough on the equipment, but it has never seen any water or mud. I'm thinking it is from wheelies, he can ride through all 5 gears with no problem. He rode over 1/2 a mile next to my bike on the rear wheels. Do u think he starved it of oil doing such a long wheelie, I know he has done that time and time again. So if anyone has any ideas what may have happend please let me know. Thanks.

 

was the compression test doen right? u let it crank more than one time correct

 

Yes, we let it crank over multiple times and same thing every time.

 

then i think u got a problem lol. low compression would be from valves not sitting on teh seat right or bad rings. does ur oil smell like gas?

 

If you've never adjusted the valves he needs to start there. My last raptor felt awful when the valves needed adjusting, couldn't believe the difference once adjusted....

 

Never even thought about the valves. I guess we'll have to check them next. I'm not sure if the oil smells like gas, we'll have to check tonight. Thanks for the tips, I'll keep you guys posted. You guys don't think the wheelies have anything to do with the problem?

 

Nope. My bike is a 720(4mm stroke) with all the goodies so I am on the back tires much more than I am on all four..... I like riding wheelies too so I don't think it has anything to do with it.

 

I dont think it is from the wheelies being that the motor is dry sump pressure lubed. But i bet that the valves are tight. That motor is known to have the valves adjusted after a period of time.