Uma Racing main jet can be use to upgrade the performance of your carburetor. With larger main jet diameter, more fuel can be pumped to the combustion chamber in your bike.
The modification of this item is usually done with modification of the exhaust to get maximum performance. A modified exhaust can consume a lot more fuel that normal exhaust, so, in order to feed the hungry exhaust, carburetor modification is needed. One part of the carburetor modification is to modified the main jet.
Uma Racing main jet is available in these sizes; 88, 90, 92, 95, 98, 100, 102, 105, 108, 110
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