# Bigger Pulley Gear/Wheel vs Smaller Pulley Gear/Wheel?

Hypothetically, you could get 2 belt driven setups - one with a big pulley gear and wheel and the other with a small pulley gear and wheel such that they end up having the same torque and top speed (bigger pulley = more torque less top speed, but bigger wheel = less torque and more top speed, so they end up canceling out, and you can get both setups to have equal tq/ts). Then, what are the differences between the 2 setups? Intuitively, it seems like the big setup would have worse range/overheating due to the extra wheel weight. Obviously the big setup is going to eat up rough roads and cracks better, but I think it wouldnâ€™t be as carvy/slidy as the smaller wheels. Are there any other differences?

Using an esk8 calculator (https://calc.3dservisas.eu/) and trying 2 extremes - 100mm wheel + 36T wheel pulley vs 200mm wheel + 72T wheel pulley, it seems like the big wheel/pulley has the exact same top speed, but actually more torque. Range is the same, and current draw is the same so I guess that implies motor heat is the same between the 2. So then youâ€™re basically just getting more comfort, more grip, and more torque for free, which just doesnâ€™t seem correct to me. Iâ€™m guessing the calculator doesnâ€™t take into account the extra mass of the bigger wheels, so you might actually end up with slightly worse speed, tq, current draw, and range?

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Assuming constant everything, they will be identical. However, one of the biggest differences that we see is rolling resistance from the wheel material. Smaller wheels tend to be polyurethane, which is pretty efficient and will roll for a long time. Meanwhile larger wheels tend to be pneumatic and rubber, which will slow down quickly due to deformation, even though it may be heavier (and thatâ€™s a maybe because solid thane is heavy!). You can even see this difference in similar sized wheels like a TB110 vs Cloudwheel 105s - the Cloudwheels will have worse range even though the setups are more or less the same.

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