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Cutting the slide on a CR250R

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So I was given a #4 Mikuni slide by a friend and decided to experiment with cutting since this was a free. The idea to cut it stemmed from the newer gen KTM Mikuni TMX carbs and the inherit problems with the factory jetting settings where the fix was to cut a grove aprox 3mm with a triangle on the engine side of the slide. I figured the same would apply to the flat sided slides of our gen of carbs. I applied the same recommended fix for the KTM but finished it off with a round purely based on what I thought would have been a smoother air flow for the pilot jet. Surprisingly my start-ups have been around to 1-2 kicks from cold rather than the usual 2-3 I found. Even with a richer slide it took a fatter pilot from a #30 to a #32.5 to make it really work well.            

Just thought I would add this to the technical part of tuning these Mikuni's carbs where some think they are not worth the hassle but I think quite the opposite. The results are interesting as the carb doesn't "seem" as sensitive to temp and elevation as before. But I only have one ride on that slide so far. I wonder if the same would work with my #5 but I am hesitant since these slide are brutally expensive. I am hoping some out there can provide similar feedback wit this sort of experimentation. 


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