Newbie driver here, why do the rpms need to be higher when in low gear? Since its a lower gear shouldnt the rpms be low as well?

Question

My brain cant seem to grasp the concept behind this sorry

In: 0

Answer 1

They don’t “need to be” higher.

The engine can ‘spin’ from a very low RPM of about 800 rpm to about 3000 rpm. Below 800 rpm the engine can stall (shut off), the engine struggles very hard to go above 3000 rpm.

The gear you select engages the spinning engine to make the wheels spin. At the lowest gear you can go from not moving to some low speed, let say 30 MPH. Your engine is working as hard as it can, 3000 rpm, to go 30 MPH. To go any faster, you have to switch to the next higher gear which goes from 25 MPH at 800 rpm to (let’s say) 50 mph at 3000 rpm. To go any faster you have to switch to the next higher gear. Etc.

It’s the same as a bicycle. In low gear you just can’t spin your legs any faster at some point. In high gear you can’t push hard enough to get started from not moving.

(note: the actual rpms and MPH in my example are just made up. When I drove a manual stick I just went by the sound of the engine, not the rpm)