Was plowing my driveway today and my '04 Eiger was having a hard time staying running. Floored it in neutral and was getting a constant tinty sounding backfire only at full throttle. No other time and no backfire when shutting it down. Backfire sound was not the normal loud crack/pop but sounding like it was resonating in the muffler sounding like a metal backfire. Any ideas

 

On my Suzuki Z250, I had that same problem. i had one of my friends father look atit, he is a mechanic, and he looked and where the gas tank is supposed to get are through a tube, well, Dirt Dobbers got in the toob and built a nest and clogged the hole so it was not getting any are...that was whole problem..im not sure if thats it but its worth a try

 

Sounds like your timing might be a little off, you might wanna just check into that.

 

i was thinking the valves might need adjusting. I had it done at the dealer with about 150 miles on it and it now is over 400 and they said they adjusted them but do you ever really know. Other than obvious valve knock what are other signs and symptoms of loose or tight valves. I don't seem to have the power I used to have. I also can not get mine over 50 mph even going down a slight grade. Going up grade I can't get over 30mph and my buddies 500ho pulls ahead of me by at least 70 yards on a stretch that is about 1/4 mile at most-Does this seem normal.

Also thought the tinty backfire could be some water in the gas but I use fuel stabilizer so I sorta ruled this out.