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The 93 TRX300EX had a #120 main jet standard
The TRX300 C3 used a 125 as did the TRX300FW
All Amazon carbs are junk - I have had no success with any Chinese counterfeit carburetors and have trashed all of them and bought used OEM carbs and rebuilt them. BTW - rebuilding a carb is more involved than installing a kit - a kit just supplies the rebuilder with an assortment of commonly needed parts that compliment the rebuilding process.
The 93 TRX300EX had a #120 main jet standard
The TRX300 C3 used a 125 as did the TRX300FW
All Amazon carbs are junk - I have had no success with any Chinese counterfeit carburetors and have trashed all of them and bought used OEM carbs and rebuilt them. BTW - rebuilding a carb is more involved than installing a kit - a kit just supplies the rebuilder with an assortment of commonly needed parts that compliment the rebuilding process.