Subtitles for How a motorcycle clutch works

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This is the right side the engine. I removed the cover
to expose the clutch on this side. I'm removing, now,
the last one the four clutch springs.
When I remove this cover I can now take apart
the clutch plates. As you'll see
this one has the teeth on the outside and it hooks up
to the outside of the clutch. This one has the teeth on the inside
and hooks up to the inside
of the clutch. I'd like to demonstrate to you quickly
what it looks like when the inside part of the clutch and the outside part of the clutch
are not moving my together.
So what we have here if I take this
first clutch plate off, you'll see we have
the plates with the teeth on the inside
rotating and rubbing against
the plates with the teeth on the outside.
What is happening is that the two want to rotate together, but because
one is not rotating at the same speed
they are creating friction and eventually with the force of friction
the two will rotate together like so. And this can happen vice versa as well.
If for example the crankshaft is spinning
but the inside part of the
clutch is
in place then we have this.
And if you could see on the other side the sprocket at this point is not moving
up until the two are able to rotate together at the same speed.
The crankshaft
through these sprockets turns
the outside part of the clutch. The outside part of the clutch
is what is linked to the to the movement of the piston
and the inside of the clutch is what is linked
to the sprocket through the transmission and
here's where the two of them
become synchronized. When we
let go of the clutch we are allowing these plates to rub on each other
and eventually, through friction, to turn at the same speed. I have the clutch reassembled
and I'm going to demonstrate to you what it would look like
if we were pulling on the clutch lever
on the left side of the handlebar. This is where the
cable to that clutch lever is attached to normally
and when I pull on it
you can see, the clutch cover
separates. Let me zoom in so you can get a better look at that.
Now I'm pulling on it. Even though it's a very small
noticeable difference
As you can see here I'm pulling on it
and now I let go. Pulling on it...
Let go... so the clutch cover moves away
pushing up against the clutch springs
thereby reducing the friction between the clutch plates.
Let me demonstrate this.
Pulling... let go... pulling... let go. When we pull the lever
on left side is the handlebar we're pulling on the clutch
and the cable that is attached to that lever--
the other end of it is attached to here on the top of the engine.
Now let me explain what that does.
It is held in place by this screw which I have already loosened
and it has a spring on it
which is how this thing comes back to its
position back here. When we pull the clutch lever
it's actually moving forward like this and what this does...
Let me pull it out for you to see. If you see here, the bottom of that
rod has that shape
so when we pull the lever it turns like so
and the effect of this is [...]
it's moving a rod.
There's a rod that pushes up against
the bottom of this stick
about here and
what it does with that is [the stick] pushes that rod to the right side of the engine.
Let me explain that from the other side.
If we follow the rod that the other end of the clutch
cable is attached to, as you can see, it's actually coming up the other end of this shaft
and what it's touching on is this rod.
This rod sits inside here all the way to the other side
and on the other end of it
is this ball which is there to reduce friction
and the clutch covers. This clutch clover
sits inside of that shaft
and so when we pull the clutch lever
pushing this rod out towards us
what it does is it pushes away the clutch cover and that is how we get
the reduction in friction between the clutch plates
because this clutch cover... it's mounted
onto the clutch with these
clutch springs and those clutch springs
are what increase the friction between the plates. So by pushing
the clutch cover out we are
allowing more space between the clutch plates
and that reduces the amount of friction.

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The engine is from a 1981 Yamaha SR250