Why do most motorbikes / cycles / scooters have the rear wheel powered, as opposed to most cars, which have the front wheel powered?
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It’s usually easier to push than pull. However, cars are easier to control with front wheels pulling especially when roads are slippery.
FWD requires fewer parts, is less complicated, and is cheaper. For this reason it’s used in most cars.
But motorbikes turn differently to cars that makes them unsuitable for FWD. In a car you turn the wheels to move the car. But in a bike you can lean as well as turn the handlebars. But if you had a chain between the engine and the front wheel that would make turning the handlebars difficult.
Short answer is because the steerable wheels are in front and it’s mechanically simpler to isolate steering from driving(the “to make something move” sense). Another short answer for why the steering is in front is to allow for higher speed while turning (without losing control). The back of the average car doesn’t swing out while turning unless you engage the turn at a high speed because the wheels have a tendency to move forward 9r backwards, not sideways. If the steering is in the back, the back of the car will fling outwards more easily (due to the wheels pointing outwards instead of straight ahead)
1st big thing, most cars are FWD because its easier to produce, the engine, gearbox wheels, suspension and structure can be built outside the car and lifted into it as one piece. This isnt as much of an issue on bikes.
2.) It would be very difficult to get drive to the front wheel of a bike, unlike a car there is no good path from the engine to the front wheel.
3.) Bikes steer very differently to how the layman thinks, its actually very complex rotational inertia stuff that relies on crazy physics things… it works best with a driven rear wheel.
Source – Im an ex car mechanic who rides bikes.
There is some convergence of benefits for cars.
Fwd on a car is cheaper, plus it’s easier to drive. If the car is under steering, hence you are going straight on a turn, removing throttle will automatically correct it and make you oversteer. That’s a good feature for cars intended for non experts.
For motorbikes, there is a lot more power/weight ratio. This means a forward driven bike would have some handling benefits only with very low power, like an electric bicycle. Anything above that, and your front wheel will spin uncontrollably when you accelerate. Read drive uses the rear wheel and when you accelerate the whole weight of the bike goes on it, allowing more grip, so more acceleration and less skidding. Plus, if you put an engine on the front wheel, you have to steer the wheel and the entire engine weight with the handlebar, super uncomfortable and dangerous as you can’t react quickly.
Add in that read drive is cheap to make for a bike and you get why it’s done so often, there are super rare fwd bikes, they are just awful to drive.
Larger vehicles such as trucks and SUVs are typically RWD. This setup has the engine supply output power, into a transmission, through a driveshaft, down to the rear axle(s), turning the rear wheels providing thrust. Similarly, a motorcycle has the engine supply power to the transmission down to a chain or belt, to the rear wheels providing thrust.
Both are RWD and steer from the front axle.
A FWD vehicle has an engine supply power, to the transmission and out CV axles to the front wheels providing pull. Because the power wheels are the same as the steer wheels, a simple straight connection is impossible, mechanically speaking. A motorcycle could *theoretically* be FWD, it would change all the physics of the bike. The centralized location of the the engine and transmission under the rider is part of how it is balanced. A car/truck with 4+ wheels is more stable and allows for many different configurations: front engine/rear drive, mid engine, rear engine/ front drive, rear engine/rear drive, even an engine mounted behind the rearmost axle with a shaft to the rear axle (I know them as diesel pushers on motor coaches/RVs).
You can’t run chain drives to the front of a bike very easy. A direct drive on a bikes front wheel would work but the motor would have to be very small so not much power from a gas motor. Other options rub on the front wheel to power them, still has to be small.
There are new electric bike motors that fit between the forks and are also the front hub.
Cars just have more room for bigger engines and a more complicated mechanism for turning and driving.
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