Originally Posted by adkfreeridex
here are two pics of the plug (one with flash and one without), i tried to compare them with photos of plugs on the internet and my conclusion is that im running lean, can anyone confirm this? however, If i am running lean, why does my problem get worse with altitude?
I can't answer any altitude questions.
But looking at the available specs from the XR650L engine it would seem that the usual jetting for over 5000ft is 55 pilot and 155 main,
All bikes are different, but I would strongly recommend Daves Mods its not just richer its also the way the mixture is delivered at different throttle openings.
Raising the needle is easy enough and reversable if necessary,
What condition is your air filter in? Its easy for them to get all clogged up with the oil mist in the airbox.