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Can someone tell me what "slippin the clutch" means?

if im not mistaken...

it's when you use the clutch to manage power output.

this is very important in doing launches since you are on WOT and w/o proper slipping of the clutch... you will loop the bike, stall it and dump it or whatever.

For some odd reason i had the strongest feeling that YOU of all people would get back to me first

but yeah doesnt it have something to do with doing wheelies?
not saying im gonna do any but just curious what slipping the clutch meant

Yngvai X wrote:Can someone tell me what "slippin the clutch" means?

Slipping the clutch is when you're allowing only a part of the power to the engine to get to the rear wheel.

When you have the clutch fully disengaged, the engine flywheel is not in contact with the clutch plates, so there is no power being transmitted to the rear wheel. When you have it fully engaged, the flywheel and clutch plates are pressed together tightly and move together, transmitting all power to the rear wheel.

When the clutch is partially engaged, the plates and flywheel are touching, but they're moving against each other. They're essentially grinding against each other the way a brake pad grinds against a rotor. So there's some power being transferred to the back wheel because the engine flywheel is making the clutch plates move.. they're just not moving as fast.

In practice, what this means is that there is a "friction zone" on your clutch lever between "fully squeezed" and "not squeezed at all." This lets you smoothly change gears. It also lets you use the throttle smoothly, especially when moving slowly. When in first gear, small changes in throttle can cause the bike to jerk between coasting and accelerating. Letting the clutch slip in this situation means smooth power delivery.

Let me elaborate a bit (ha!)

With the clutch fully disengaged, the rear wheel and engine are completely independent.

With the clutch fully engaged, the rear wheel and engine are directly linked. If the rear wheel stops with the clutch fully engaged, the engine will stall because the crankshaft is no longer moving.

With the clutch partially engaged (slipping), the engine is transferring some power to the rear wheel, but they are not fully linked. The engine can still be running (turning the crankshaft and flywheel), but the rear wheel can be stopped. The bike will be trying to move forward, but holding the brake can prevent it.

I'm clearly having a hard time explaining it well. Sorry.

And yes, you can use this effect to pop wheelies. You can rev the engine while slipping the clutch. When you fully engage the clutch, you will get a lot of power instantly transferred to the rear wheel without the excess jerkiness you would get by just slamming a fully disengaged clutch closed since the clutch plates and engine flywheel are already in contact. This is what they do in drag racing and so forth.

Yngvai X wrote: but yeah doesnt it have something to do with doing wheelies?
not saying im gonna do any but just curious what slipping the clutch meant

if you want to do a wheelie from a stop, then yeah... you need to know how to slip the clutch.

yeah a little hard to grasp what your saying lol..

I dont think its from a stop.. is it? Some of my buddies slip the clutch while there on the highway going 70-75 and pop it up to do wheelies..

I figured you would know this stuff for sure verm. dont you do wheelies?
haha

Yngvai X wrote:yeah a little hard to grasp what your saying lol..

I dont think its from a stop.. is it? Some of my buddies slip the clutch while there on the highway going 70-75 and pop it up to do wheelies..

I figured you would know this stuff for sure verm. dont you do wheelies?
haha

You can slip the clutch at speed, too. While on the interstate, you could be revving the engine high while slipping the clutch.

Doing this, you can maintain your speed. As soon as you fully engage the clutch, though, the power delivery to the rear wheel will increase instantly, causing a wheelie.

Think of it this way. Say your bike requires 30HP at the rear wheel to maintain a speed of 70MPH. Revving the engine to 3000RPM normally accomplishes this. But if you rev the engine to 9000RPM, where it produces 80HP, you can slip the clutch so that you keep 30HP at the rear wheel to maintain your highway speed. The "extra" 50HP of energy is getting dissipated by the clutch plates spinning against each other, the same way a brake pad dissipates energy by spinning against your rotor.

As soon as you fully engage the clutch, you instantly lock the clutch plate to the engine flywheel and have all 80HP of the engine power going to the rear wheel. This dramatic increase in power to the rear wheel can result in a wheelie.

In this case, you want to slip the clutch for two reasons:
1) To maintain your speed while you get ready to wheelie
2) So that you don't get a huge jolt by physically slamming the flywheel and clutch together by engaging the clutch. When you're slipping the clutch, the clutch plates and flywheel are already in physical contact.. there's just not enough pressure applied to them to "lock" them together.

http://auto.howstuffworks.com/clutch.htm

There are some nice diagrams showing actual operation of a simple clutch that should make it a bit more clear.

Ok I understand alot more haha.. so that would basically mean pulling in the clutch to your friction point and revving the rpm's up and 'dumping' the clutch or whatever so you get that instant boost of power which then causes a wheelie..?