The Clutch

What a wonderful device the Clutch is and such an argued about control.

Should I use the clutch to change gear? You need finesse with the clutch it’s not a switch? Don’t slip the clutch? The clutch is for changing gears nothing else? Etc etc etc.

I’m sure whatever I tell you here you will get someone to tell you something else and argue vehemently that they are correct.   So I will state from the outset that these are my opinions and I will try to give you solid understandings of why.

A brake in reverse?

So how does the clutch actually work, I mean what are we talking about here first and foremost.

Well firstly the clutch is a little like a brake but with some major differences.  Its job is to stop the power going to the gear box so that you can change gear.  Strangely enough with power driving against gears they don’t want to move.

It works by having plates like brake pads mixed with plates like brake discs spinning on the same axis.  Springs push these plates together and unlike your brake pads the only thing that stops the discs from following each other around is eventually the back wheel.  Your clutch lever simply releases the pressure on these springs and allows the plates to slide past each other, sort of like loosening the brake lever.

There are a number of different types of clutches the main ones we should be interested in are DRY, WET and SLIPPER.

A dry clutch is a clutch that does not have engine oil flowing around it; a wet clutch does have engine oil lubricating it.  The main difference we are concerned with here is the abuse each will take.

A slipper clutch is a clutch that is designed to help you with poor use of the clutch in down shifting.  It allows the clutch to slip in one direction only under pressure so that the back wheel will not lock (or is reluctant too).  If you were fully skilled in the use of the clutch you wouldn’t need a slipper clutch just like all the riders for years before you.  But it does save you from those horrendous mistakes and also in racing can allow you to abuse your down shifts to your advantage and put your focus onto other things.

So just like your brakes the clutch will wear out and does suffer from getting hot and the more you abuse it or the hotter it gets the shorter its life will be.  Wet clutches take more abuse because they tend to stay in a narrower range of temperature dictated by the oil cooling of the engine, whilst dry clutches are renowned for short lives and grabby engagement.  There advantage by the way is that they are less prone to slippage whilst they are fresh and ability to hold more power with lighter weights.  Good for racing where you change them frequently.

So your clutch will wear out and will need replacing, abusing it will mean this happens sooner.  But you are already talking about a component, like your brakes, that you expect to wear out.

Always an argument.  The truth as far as I am concerned is a little of both.  When you are stopped at the lights and about to drive off, things will get way too exciting for you if you just dropped the clutch like a switch.  Either that or you will just stall the bike.

So; certainly when pulling away you need to use the clutch like precision control, also when doing fine slow speed work or in such cases as the mighty Wheelie!!!  but when changing gear on the move, like a switch.

Is slipping the clutch a No No?

Doh, if you use the clutch as a fine control by definition you are slipping it!!!  More importantly it is designed to slip and allow you to control your bike via this mechanism.  Possibly one of the reasons most modern bikes have wet clutches for longevity.  They are designed to slip.

You might also see real benefit to slipping the clutch.  Just take the scenario above where slow speed corners become so easy with a slipping clutch.  This means pulling out of a drive, doing a U turn, parking and so much more.

So I should use it like a switch?

Are you kidding, why would you want to pay so much of your precious attention to the clutch when you are changing gears etc when you don’t have to?  Let alone the fact that each gear change is a transition and you want to get back to your set as fast as possible or if possible not upset it at all!! Of course you want to use it like a switch, in fact if possible you might like to ignore it altogether.

So do I need to use it to change up?

No, except for a few bikes or for those big transitions like from first to second where you need the clutch on some bikes.   I’ll cover that off in more detail in the section on gears.

Where I will also cover off the stupidity that says you can change down without the clutch.

So what else do I need to know about the clutch?

The clutch controls power delivery through the gear box, it does this by removing power from the drivetrain.  In all situations except for taking off, stopping and a few control scenarios removing power is the same as back off the throttle, it can induce a transition when it’s not wanted.  There is one very big difference, when you slip the clutch you still have drive keeping things under tension, just less, when you roll off the throttle you cause engine braking.  This difference can be used to great effect in slow corner situations, such as hairpins and round-abouts.  Do it right and you can avoid the snatchiness you get on bigger bikes.

We should use the clutch in the manner that is appropriate to the purpose and we use it for many purposes. Sometimes progressively, sometimes like a switch, sometimes ignoring it altogether.  Knowing when and how is covered off further throughout the book.  But basically you use the clutch to take, you possibly use it to change gear, you use it when you stop.

The only other times when the clutch should see action is for some stunts like wheelies, burnouts etc.

A possible exception to this, although I would say get the gearing changed, is to keep a bike in the power band, like a smaller two stroke in a slow tight corner.