XR600 TM40 jetting advice sought.

I have just ordered a TM40 from Allens (UK mikuni importers). They were a little vauge about what jets it comes with, saying it comes jetted for your XR600? I assume it will be jetted for a standard XR600 then. My Xr has no airbox lid and an Arrow slip on can. Anyone else got this sort of set up with a TM40? What jetting are you running? Or, if it is jetted for a stocker, what sort of increase am I looking for on the main and pilot?

Many thanks


My TM40 arrived this morning. Just having a look at it now. It comes with a 130 main jet fitted. It also has a 132.5,135,137.5 and a 140 supplied with it. Any ideas on what main jet to put in it if the bike has no airbox lid and a slip on race can?

I seem to be drawing a blank on jetting advice for this carb? I thought the TM40 was a popular replacment? Anyone? Bueller?



trial and error my friend! start low, if you develope a hesitation or flat spot in the acceleration then bump up the main size! the stock is a #152 so i would gander to guess go with the 140 initially. but best bet is to experiment with the carb in your environment!

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