I have an 03 eiger that has been giving me problems for the last year. It is very hard to start when cold, after it does warm up it pops/backfires through the back of the carb. It does not have a constant idle as it revs up and down slowly. While riding it it does ok if while giving it constant throttle. When I turn it off after riding it, it seems to have built up pressure and backfires, or whatever you want to call it, it goes whoop!!! through the exhaust immediately when its turned off. I have throughly cleaned the carb twice and this did not help, new plug also. It has 750 miles on it. Not sure if this is a timing problem or valves need to be adjusted. Any advised would be appreciated.

 

Check for intermittment spark. Use your old spark plug and ground it while holding the start switch for severl secounds. This is an easy check and let you know if you have a spark problem.
I played with my carb/valves for 1 1/2 years and finally found intermittment spark (had to replace flywheel--all magnets came loose). Mine would also die from time to time. and would do as you stated depending on how I set up the carb, rich or lean.

 

check valve clearance, sounds like a valve not sealing in the head. the deal with the timing could be the issue also.

 

Ok I see you 03 is actully an 02 and your looking for a service manal. No big deal, not much difference in them and use the same service manual. Did you check for intermittent spark yet?

Service manual try this link. http://www.sell.com/23Z9F9

There is a difference in the manuals for auto and manual transmittions.

If there are any spec you need before getting a manual just ask!!