Aftermarket exhaust on Rx1 2003, re-jet?

Do I have to re-jet the carbs if I'm going to run with a excell exhaust?

Anyone have re-jet only for changing the exhaust to any aftermarket / under tunnel ex... ?

Different speedshops for sleds tell me that just looking at the color on the spark plugs, cannot really be trusted on theese engines.

What do you guys think?

Now i run completely stock engine with stock carbs (except the float bowl update) and the excell exhaust.

/Bjorn
Sweden

Well, I'm not really sure. I think I may hear something like missfire when I go from 0% to 100% throttle.


I did run this way half previous season, I hope it haven't gone that lean that pistons etc have taken damage :/
Most of the time were in the mountains but did some miles in sea level, and thats where I am now...

How much did you raise your needles?