alright, i have been having a heck of a time with my valves. i adjusted them like 2 months ago, because they had tightened up really bad and my 4wheeler just stopped working. then we adjusted them... we lined up the i with the mark..... and then we adjusted the intake at .006, and then we adjusted the exhaust at .008. we had the book on the raptor.... and the yamaha mechanic told me what to do.... he is a friend, so i doubt he lied to me. well, we put it back together and tried starting it, and it sounded like it had so much compression that it couldnt even turn the motor over, and then the starter relay in the back burned out...... so we left, and his dad fixed it, but didnt tell us what he did..... well now i got the same problem, i adjusted em last night...... and the same compression thing happened...... his dad is out on vacation, so i need some help figurin it out.

 

Make sure your battery is fully charged before you try to start it. Or use a jumper. When you hit the start button does the starter solenoid make a clicking sound?? If so your battery is dead.
It's VERY unlikely adjusting the valves will give the motor so much compression it won't turn over.

 

You cannot only line up the I with the mark. You will see that I twice in a full cycle of the motor. You have to turn it until the mark is lined up but at the top of the compression stroke. There should be clearance between all valves. If not, turn another full cycle and check them again.

 

Yeah what 1Less said. When you turn it over counter clockwise watch the intake valves go down then back up then another half a turn. Your exhast valves should be OK and have enough clearance. you should be able to feel the those move when your at the right spot.

 

I had a similar problem when I adjusted my valves. My bike wouldn't even turn over and I couldn't figure out why. I finally realized I adjusted my valves at the beginning of the intake stroke. Take off the valve cover for the intake valves and turn counter-clockwise until you see the intake valves start to open. The "I" mark will show up when the intake valves go down, keep turning and wait until it comes up again. Now you are on the compression stroke and can make your adjustments. Hopefully this will fix your problem.

-Brandon