I adjusted my valves in my prairie and now when i start it is fine and it runs great but when i rev it it back fires is it my exaust valves that i adjusted wrong or is it the intake i realy need to get it fixed if anyone could help me on how to fix it thanks.

 

Hello again Mudlite, double check your valve adjustments, they may be out. I have only done the valve adjustment once and I found it tricky. You have to make sure the piston is at top dead center on the compression stroke to do the adjustment.
The T mark will also line up on the exhaust stroke.
When I did mine, I found the valve adjuster to be very tight, so I backed it off to 8 thou. clearance but I wasn't sure it was right, so I turned the engine over several times with the pull start (slowly), and found that the valve became very loose at TDC.
I re- adjusted it at this position and it works great. I think maybe the compression release mechanism may interfere with the setting.
Try it again, and then watch the valve operation/clearance when you slowly rotate the engine to make sure it's OK.
I didn't touch the intake valve because I only heard about the exhaust valve being a broblem with tightening up.

Good luck