Help!!!!!!!

[motox450]

Hey everyone. I just installed my stage 2 hotcam and now my quad won't start. It tries every once and awhile, but it won't fire up. When it does try it backfires like crazy! What did I do wrong??? Help Please!!!!!

[450robot]

did you make sure you had the timing chain on in the right spot?

[motox450]

Yes all of the timing marks line right up. I checked and reshimmed the vavles and they are perfect. The auto decompresser is fine as well. I am lost here? I don't know what else to check.

[rodenberg35]

I had the same problem only not as bad. mine would back fire at half throttle I had it apart about 5 times. then it just stopped I always had the timming right and never found out what is was. I did notice earlyer today the I had a set of marks on my cam that look like the cam is rubbing on the spring cups before it should dont know if its enough to open the valves though

[motox450]

First thanks everyone for the help but I think I figured it out. I checked my airscrew and I was less than 1 turn out. So I went to about 3 and it fired up after it backfired first time. It does run fine. I think I am still lean on the pilot, so I am going to get a 48 and 50 pilot and see which one works. I am running a FCR carb and it came stock with a 45. It ran fine until the cam so I guess it made a big enough change. Thanks for all the help.

Russ