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June 25, 2017

Motorcycle Transmission

by biker1

How a motorcycle transmission works

See how a motorcycle transmission works using an open fixture and small electric motor. You’ll see a motorcycle transmission shifting and changing gear ratios

After you watched our moving transmission. You will have a better understanding about how a motorcycle transmission works.

This is a constant mesh transmission. What it means is that the gears are always in mesh. They don’t slide in and out like a synchromesh this is constants.

What happens is we use dogs here. These are gear dogs, they slide in and out of accompanying gears. To engage the driven shaft, to the out put shaft.

The clutch basket turns here, so that when the engine is moving, it’s actually moving this shaft right here, it forces the power through, and depending on what gear set we have we will have a power ratio determined by the drive gear and the driven gear.

How a motorcycle transmission works

motorcycle gal

This is what we call a shift fork. We’ve got three of them in this transmission. This is a six speed. We’ve got a shift fork for the different sets. These shift forks are controlled by this shift drum.

This is the shift drum. The reason motorcycles goes from a first neutral second and third in sequence. Is because this rotates, clockwise or counter-clock wise. And in doing so, it controls and make the movement of the forks so that only one gear is chosen at a time.

You can imagine different gear ratios and what would happen. You’ll have an exploding transmission. So this not only moves and changes the gear, it also controls where the other two are in the cycle.

The shift drum is turned by this ratcheting mechanism this ratcheting actually comes on the outside and as we turn it, we’re moving it one notch. We let it go, we move it again. It’s actually turning.

This controls the movement of the gears. Up one or down one. This is the shift mechanism.

Of course our transmission runs in the bottom of the crank case. They love oil so the first thing we’re going to do is we’re going to lubricate this transmission.

This is neutral Of course this is the drive train this is what drives the back wheel.

This is neutral you can tell that the imput shaft is turning while the output shaft is still.

First thing we’re going to do, is I’m going to put this in first gear. Watch as I move the fork. You can see here the shaft is turning.

That was first. What we’ll do now is that we’ll go into second. Now we see second gear engaged. We’ll go back into neutral. We’re going to go into third. We’ll go into fourth.

There fourth gear. Now we’re going to go into fifth. And lastly we can go into sixth. Ok now, we’re going to slide it back into neutral.

How a motorcycle transmission works



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