Yamaha TRX850 Enthusiasts Forum

My carburators have all standard jets according to Cobba's post, BAR the Main air jet that is 145....nearly twice the standard size.
Unsure of main jet because it is not marked. Presume it is standard 142.5 ?? Wonder if the last chap that worked on the bike confused the starter jet for the main jet??
How will this very large starter jet affect me??

Do I replace it with size 83 jet....?

currently running K&N filter and straight open 2 to 1 pipe.

Swap them around and try it, sounds like a possible culprit to me....
Some people just put 1 or 2 size larger main jets in place when they have fitted aftermarket pipes without getting a starting point on A/F to start. Nothing unusual for most carb bikes to run rich from standard.