Reduce rotating mass for Box Stock Predator


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Rotating weight is a whole new ball game. Everything attached to the crank outward needs to be lighter and everything in the engine that attaches to it or is worked by it needs to be lighter. External parts are wide open like the Wild West ..internal parts all get checked and need to fall in spec.


All I can think of is to: drill holes in everything, acid etch the inside of the axle, ceramic bearings, magnesium Sprint wheels and fancy alloy wheel nuts. This is interesting.

95 shaw

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Thin cut tires, especially treads. Smallest, lightest wheel hubs. 219 chain and sprockets. Throw the gear guards away.

Weight farther from center of rotation has greatest impact.
Spend your effort on those first.

Etch center of axle?
C'mon man
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Not saying I bent any rules..... but

Put your hubs in a lathe and remove everything you can. Also, shorter studs will help when you're counting ounces. I suppose you could look at cutting the axle down a bit if you wanted, but I wouldn't.

Easiest, best, and most legal way to do it? Buy the best bearings you can afford.


Titanium nuts and bolts on anything spinning on the axle. Shortest hubs possible. 100% ceramic bearings are lighter. I would not change your axle though from what the kart was designed with unless you are drag racing. The corner speed is much more important. Rotating mass is highly overrated when talking about axles.