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Help with Mattawa Jetting 02 YZ250

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I am new to 2strokes/jetting and I know there are a few WA peeps on this forum who ride Mattawa, who might share some knowledge! I Ran a 182 main jet with the needle 3 clips for the top last weekend at Mattawa (about 60 degrees out)and it still seemed lean at WOT in the sand. My buddy has a CR250 and we tried a 250 main in his and it seemed lean too possibly. I checked the plug on my bike once after a extened 3rd gear WOT and it was pretty grey looking. Both of our bikes seeemd hot and had white smoke coming out of the pipes after wailing on them on big hills and in the sand not sure if this is farily normal for Mattawa styl e riding or if it's an indicates a tuning problem. Anyway I checked the database and not one bike was running a main bigger than 180 so I am wondering if I should try a bigger main or basically if I am gonna blow it up?

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Interesting.. :banana: That should be plenty rich... Is it possible you're both burning coolant? White smoke is an indication of steam which means you may have a head/base gasket issue allowing coolant into the combustion chamber.. However, they will usually foul a plug right quick if thats the scenario..

Do you run any race gas or octane boost? What oil and ratio?

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Interesting.. :banana: That should be plenty rich... Is it possible you're both burning coolant? White smoke is an indication of steam which means you may have a head/base gasket issue allowing coolant into the combustion chamber.. However, they will usually foul a plug right quick if thats the scenario..

Do you run any race gas or octane boost? What oil and ratio?

We are both running 32:1 Synthetic Dumontec, have newer top ends, and neither bike has fouled a plug since we owned em.......hmm.

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Are they pinging or detonating that you can tell?? Are you overflowing coolant when you stop?? You're plenty rich and likely in the clear, but dont take my word for it over the net... :lol:

With a stock motor I ran a 180 main, stk needle and a 48 pilot at Mattawa.. 40:1 Maxima Castor 927 :banana: I think you're safe

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