It's a round slide carburetor, common in classic motorcycles and powersports equipment. This model may be found on Honda CL90 and S90 models. It could also be used on other motorcycles or ATVs. Proper tuning is essential for optimal engine performance. Flat slide carburetors can offer performance improvements over round slide types. The Mikuni brand is known for reliability and performance. Carburetors need correct fuel metering for various conditions. Believed to be a VM22-133
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