I recently bought a 95 xr600. It had been sitting in a garage for at least a year. I was told it needed rings.I did get it running befor tearing it down. It did smoke and backfired.The backfiring was worse when it warmed up.After changing the rings the bike was much easier to start but still cut out and backfired.But it will idle on choke.I rechecked timing it was ok,I adjusted valves,they did need adjusting.Then I started looking at tha rest of the ignition.I do have a repair manual on it.After checking the componets it seems it is the cdi box.Does anybody have any suggestions. Thanks,Hambrick PS the spark is a reddish blue and I did have the coil tested at a bike shop.