Other than ticking/knocking what else. I'm not sure if this is related but I had my valves adjusted at about 150 miles and from that point on I thought the valves made more noise than before. I know have over 420 miles on it. '04 Auto Eiger BTW. I have noticed that I seem to be lacking power going up a slight mountain grade. Can't get over 30 mph while my friend on his '05 Sportsman 500ho blows by me and is about 70 yards ahead of me in about a 1/4 mile stretch. I also can not get it over 50mph on a straight away or a very, very little downgrade(smaller downgrade than mentioned above).

Seems to be sluggish going up a trail slope and when making a turn it takes awhile for it to get back and going while the Polaris just crusies up . might just be the engine size but wanted some opinions. Also, had some tinty backfire from the exhaust at full throttle only. If I was in neutral and hit throttle to fully open it would start to backfire until I let off the throttle. Does not do this partially open or pushing on the throttle. could all this be valves or something else or is the sluggishness I described normal because it's a 376cc engine. Everyone post they can go over 55mph on their Eiger. not me!

 

It wont matter how well you get the Eiger running...its never gonna catch the sportsman. Just the facts.
Some signs the valves arent ajusted right..hard starting, low compression, and like you said...noise.
Usually backfire is caused by lean conditions, or timing issues. Seeing how the timing is fixed, yours is most likely due to carb. Try pulling on the choke, next time you get the back fireing,and leave the throttle position the same... if it gets better or goes away...the jetting is lean. If youre wide open, then its the main jet. The reason it backfires in nuetral, is youre bouncing off the rev limiter.
Its better to have the valves slightly loose than slightly tight.

 

hmm..i haven't ever had the valves adjusted on my Eiger and it performs great...can hit just at about 58 or so and plenty of power...can even get it to wheelie on a good day..real good day..lol

 

if the valve needs to be re adjusted then...the quad will not satrt up good(mine didnt even satrt we had to pop start it). also, sometimes it will backfire if u just mat the gas. u will have a power loss and a excelleration loss. is that what u meant by what u were wondering?