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Mikuni TMX needle info

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Just finished rebuilding my new-to-me 2002 CR250. It was apart when I bought it so I have no baseline "seat of the pants" reference as to how it should feel. It was set up for ice racing so it was very rich (420 main, 37.5 pilot, etc). I have put it back to stock except for the needle (380 main, 32.5 pilot). The stock needle for summertime temps at my elevation (sea level) is a 6BEY30-74. I ordered that but since it hasn't come in yet I used the needle that was in it just to fire it up on the stand. It's a 6BEH1-71. It appears to be an optional needle for the 2001 CR250.

Bike fired first kick and ran beautifully. Just revving up on the stand it was crisp with no bog. May be different under load, but man it sounds nice! Forgot to mention it has an FMF Gnarly pipe.

Looked for a chart of TMX needles but can't find anything. I'd like to know the difference between the needle I have and the stock one. I'm sure it's richer at 3/4 throttle, but what about 1/4? I still have to relace the rear wheel before I can ride it. Hoping to do so next weekend. It's getting cool here in Maine and I'm wondering if it will be rich enough with the 71 needle.

Thanks in advance!

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Use stock CR needle, tune it with the nozzle, most guys out here run 2 sizes leaner in the woods. Colder temps the stock (rich) nj and jn should be safe. don't let the main sizing bite ya, warm it up good before you wfo it.

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