I recently rebuilt my 06 yfz 450 and tried to start it last night with no luck. Checked the valves I had 15 and 17 on the Ex and 7 and 7 on the two outer valves of the intake but the middle one was almost at 0. I have spark, gas, and compression. Are the valves good or would I have to put them to spec? And will it run with only that one valve being REALLY tight?