Burning out the clutch ?

[Tom P]

From another thread. When stopped...

the gear lever (which is in neutral of course if you are waiting - or you burn out the clutch as I did on a R1150RT).

Is this true, will you burn out the clutch prematurely by holding it in at stop lights?

[Jim VonBaden]

Totally false. The only, very slight risk, you take is a slight additional wear on the throwout bearing, such as it is.

 

MSF instructors usually recommend you keep it in gear in case you need to make a quick move.

 

Don't sweat it, you are doing fine.

 

Jim

[BobFV1]

Jum's correct about clutch wear and about the MSF's position.

 

Before hydraulic clutches I used to be paranoid about cable wear, but that's not even an issue any more.

 

To get better clutch life try to concentrate on smooth, crisp engagement rather than "twisting and ripping".

[ShovelStrokeEd]

It's nonsense.

 

The clutch will only wear if it is not fully disengaged, unlikely with this design, or if it is slipped excessivly on startup. Even there, it would be difficult to 'burn one up'.

 

It might stink a bit but, clutches are remarkably robust things, even our 'fragile' BMW clutches. Would take a real ham fisted fool or someone totally insensitve to things mechanical to burn one up.

[KMG_365]

The clutch will only wear if it is not fully disengaged, unlikely with this design, or if it is slipped excessivly on startup. Even there, it would be difficult to 'burn one up'.

 

It might stink a bit but, clutches are remarkably robust things, even our 'fragile' BMW clutches. Would take a real ham fisted fool or someone totally insensitve to things mechanical to burn one up.

Well, Ed I'm going to have to disagree with you on this one. RT-P's eat clutches for breakfast. Most LEO's "grew up" riding wet clutches on Kawasaki KZ1000-P's and you can slip them all day long with no problems, in fact they need to in order to do a lot of what they're asked to do on those bikes! It is a difficult transition for many of these riders when doing slow speed stuff especially and the CHP's R11XXRT-P bikes out here usually get two new clutch plates before they're retired at 60,000 miles and the third one is around half gone.

 

It would really depend on the way you ride and if you're used to slipping your wet clutch a lot every time. If you pound it and ride it hard in the twisties you're a candidate for an early replacement. Every time you "smell it" and go: "Whoa, that stinks!" you've just taken a few more microns of thickness off the plate and you've only got a finite number of those before you're below the wear limit. I've got almost 100,000 miles on my clutch (and I've smoked it a few times learning the dry clutch when it was new), but mine are mostly touring miles where it's fully engaged and not slipping. Of course, YMMV!

[ShovelStrokeEd]

Not to disparge them but LEO's ride those RT-P's like ham fisted fools.

 

The clutch design will not dissipate heat like a wet clutch will and if you ride it that way you will, of course, destroy it in short order.

 

Fast runs through the twisties should have no more effect on the clutch than riding around in city traffic. It is adequate to sustain the HP of the bike. We might give them a bit more abuse as we tend to load them up with all sorts of gear and then still beat the snot out of them in the twisties.

 

I did kill one BMW clutch on my turbo K100 but that was at roughly twice the HP of the stocker and I had a slick on the back of it.

[No_Twilight]

Not to disparge them but LEO's ride those RT-P's like ham fisted fools.

 

Sometimes I wonder if that should be my moniker, "ham fisted fool." I think you guys have adequately answered the original question so I'll ask a followup.

 

Recall that I've only been riding a little over a year but I've been learning fast. I have put over 16k miles on my 95 R11RS commuting and weekend pleasure riding. I ride very agressively when traffic and road condidtions allow it. I haven't smelled the acrid clutch smell for a while but I used to smell it every once in a while (bad shifts). I usually make smooth shifts, matching RPMs well for the new gear but I still blow it every once in a while. (as an aside, I think this wears the rear tire more than anything else).

 

On launch from a stoplight I apply power and clutch at a very similar rate to what I used to do in my sports cars. Of course the bike accelerates much faster than the sports cars did. I get the bike quickly in the power range while engaging the clutch smoothly for a smooth launch. I never get the RPMs up near the redline but in the midrange, the torquy boxer engine provides a lot of motive force. So I notice the cars getting smaller in my rear view mirror at a suprisingly quick rate. I'd guess that I'm generally going 0-60 in the 5-6 sec range but I haven't timed it. I have had fast cars race me and it's about even if I do my normal launch and 5 sec is normal for a stock street racer like a corvette or a high output mustang.

 

So the point of this lengthly description is that I'm just assuming I'll be replacing the clutch one of these days. That is one of the things that makes me think I need another bike in the stable since I don't want to be without a bike while I do the replacement. (No, I don't trust shops to do it.)

 

So my question is: Do you think my driving as I've described it is killing my clutch or am I riding like every other 48 year old kid on a BMW does?

 

Cheers,

Jerry

[upflying]

Very true. I was a ham fisted, slip clutching, slow speed riding LEO when I was riding a wet clutch Harley and someone else was paying for the repair and maintenance.

Since I am now the "sugar daddy" for my RT-P, you won't believe how easy I am on the clutch, brakes and tires.

Due to the high first geasr ratio, I have learned to exploit that fine line of clutch slippage and engine stall on start up.

[KMG_365]

Do you think my driving as I've described it is killing my clutch or am I riding like every other 48 year old kid on a BMW does?

Just remember that the clutch plate is a wear item, kind of like brake pads and asking how long they'll last is hard to answer as everybody has a different driving style, carries a different load, etc. That said, the clutch only wears when it's slipping against the pressure plate. If you get on it fast and hard as you describe, but you don't spend much time in that "friction zone" you won't wear the clutch as fast. However, at higher RPM's you'll have more revolutions per second while in that friction zone, so you'll have proportionately more potential for wear. Also, if you carry a heavier load you'll need more time in that FZ to get the larger mass moving. For example, say you and your pillion loaded down heavy for a trip almost exceed the GVWR of the bike: you will definitely wear the clutch more. If you regularly use heavy engine braking (by downshifting through the gears and releasing the clutch in between each shift) you'll wear more clutch material. If you allow it to get hot while slipping it, a hot cluch will burn more material than a cold one.

 

On the other hand, if it's primarily just your sylph-like self with fairly empty (or even no) bags, you use the brakes to slow the bike and don't dawdle in the FZ--even if you ride it hard and fast--barring an oil seal failure--your clutch should last quite a while.

 

The other things that can cause problems are weakened springs (the ones that keep the pressure plate pressed against the clutch disk), and the failed seal mentioned above. To check for a malfunctioning, slipping clutch (i.e. it's slipping on it's own when you're not slipping it) is find an empty straight stretch and get going down the road in top gear at a good, but steady clip so you're up in the power band and then grab that "loud handle" and give it a good "whomp" while keeping one eye on your tach. If you don't see and feel a corresponding steady pull forward matched to engine speed, or especially if you see the tach leap up a bit without pinning your ears back--you've got a problem.

 

If you're very concerned about its life span, just try to minimize the factors listed in this thread to minimize wear and that's about the best you can do!

 

 

--------------------------------

 

 

Oh, and Ed, I'm sure none of our LEO's here would think you were being the least bit disparaging by calling them ham-fisted fools.

The demands placed on bike and rider in the course of doing enforcement work on a motor are very different from riding for pleasure, my point was merely that if you don't know what to do to minimize clutch wear it IS possible to burn it up.

[Jim VonBaden]

Along the same vein, I ride a little differently than many.

 

I take off by increasing the RPMs only to about 1500, then let out the clutch fairly quickly. At the moment the clutch is fully engaged I increase the RPMs.

 

This results in a smooth start, and I can go as fast as I like after. Certainly not a holeshot, but faster than most cars and other bikes with minimal slipping.

 

I cringe every time I hear someone bring the RPMs up to 4K and them very slowly let out the clutch over the course of 3-4 seconds.

 

Jim

[Tom P]

Thanks for the replys guys! Informative as always, thanks.

[Martyn]

Very true. I was a ham fisted, slip clutching, slow speed riding LEO when I was riding a wet clutch Harley and someone else was paying for the repair and maintenance.

Since I am now the "sugar daddy" for my RT-P, you won't believe how easy I am on the clutch, brakes and tires.

Due to the high first geasr ratio, I have learned to exploit that fine line of clutch slippage and engine stall on start up.

 

Our old workshop manager, drawing on 35 years of experience of trying to keep Police vehicles on the road used to say,

"All you need to know about Policemen is, if you put three of them in a padded cell, each with a golf ball, within an hour one will have lost his, one will have broken his, & one will have eaten it!!"

[Ken H.]

Is this true, will you burn out the clutch prematurely by holding it in at stop lights?

How are you defining "holding it"? As in - holding the lever fully pulled while you are just sitting there? Or as in 'hill holding'? That is, holding the bike from rolling backward by dragging the clutch out a bit. If the former, then no, you can do no clutch damage, it's disengaged after all. If the latter, then sure, you are unnecessarily wearing on it.

[Survived-til-now]

Tom,

I posted the thread about engaging neutral and yes, I burnt out a clutch on my R1150RT and no, I am not a ham-fisted incompetent who slips the clutch.

I rode my R1150 into the centre of London almost every day for two years (logging up some 40,000 miles in the process) including during one of the hottest summers we had on record. I'd had a couple of days wondering why my gear changes weren't smooth as usual and then the bike stalled in the middle of a 4-lane rush-hour traffic and I couldn't get it into gear without stalling. When the dealer stripped it he found the long push rod that goes right through the clutch and holds the clutch plates apart had welded itself to some kind of thrust bearing. It had worn right down when we compared it to a new part. The whole clutch had to be replaced because it had warped but oddly enough the linings were not particularly worn.....

 

So that's my story but here's what our Institute of Advanced Motorists advises - "When you stop at traffic lights you should always select neutral, release the clutch lever and cover the brakes while waiting for the lights to change. This avoids unnecessary clutch wear and avoids the danger of a sudden jerk forward which would occur if your left hand slipped while in gear" and I would add - and if some moron rams you from behind because they haven't seen the red light.

Our Driving Standards Agency teaches the same thing to basic learners.

Now I always engage neutral if the stop is more than a very short one.

[Ken H.]

When the dealer stripped it he found the long push rod that goes right through the clutch and holds the clutch plates apart had welded itself to some kind of thrust bearing. It had worn right down when we compared it to a new part. The whole clutch had to be replaced because it had warped but oddly enough the linings were not particularly worn.....

Almost none of this makes any sense. There is no bearing where the push rod "holds the plates apart." The push rod pushes on the diaphragm spring directly. There is a bearing at the other end of the push rod in the clutch slave cylinder. But failure of this bearing has nothing to do with the clutch itself. Replacement doesn't even require disassembly. And a warped anything in the clutch ass'y itself wouldn't have anything to do with it either.

 

Something just isn't adding up.

[Stan Walker]

I burnt out a clutch on my R1150RT

 

I would not call what you describe a "burned out clutch".

 

Possible a "failed throw out bearing with subsequent damage to the thrust rod", but not a "burned out clutch". That term is usually reserved to the friction material on the clutch disc.

 

Stan

[RFW]

Rubbish!

 

The worst that you can expect is to prematurely wear out the throwout bearing, but even THAT is highly unlikely with the ball-type throwouts used on BMWs.

 

Bob.

[Stan Walker]

When you stop at traffic lights you should always select neutral, release the clutch lever and cover the brakes while waiting for the lights to change

 

Given a choice of trading a clutch for my A$$, I'll sacrifice the clutch and stay in gear. Just occasionally that can prevent a rear ender.

 

By the way, with 140,000 miles (two RT's) of holding in the clutch at traffic lights, no failures. I did replace the disc on my older RT when I did a spline lube this last summer, it wasn't totally worn out but I didn't think it had another 70,000 miles of life left in it either.

 

Stan

[Tom P]

How are you defining "holding it"? As in - holding the lever fully pulled while you are just sitting there? Or as in 'hill holding'? That is, holding the bike from rolling backward by dragging the clutch out a bit. If the former, then no, you can do no clutch damage, it's disengaged after all. If the latter, then sure, you are unnecessarily wearing on it.

 

Holding the lever fully pulled in while just sitting there... was what I was referring to. Was pretty sure it wasn't "burning up the clutch" but after I read that post I wasn't 100% sure. Thanks.

[RFW]

Holding the lever fully pulled in while just sitting there... was what I was referring to. Was pretty sure it wasn't "burning up the clutch" but after I read that post I wasn't 100% sure. Thanks.

 

This is pretty obvious. Put your bike up on the center stand. Start the motor. Now, pull in the clutch and put it in gear.

 

Leave the clutch pulled in while the motor idles in 1st gear. Now look at the rear wheel, It's not turning, is it? That is one of tbe benefits of a dry clutch: there is no drag when it is released.

 

If there is no drag, then how the hell can anyone think that the clutch disk will wear out? The pressure plates are separated and at the very worst, just lightly grazing the friction disk without transferring enough force to even make the wheel turn.

 

It should be clear that the disk cannot wear, if it is just floating between the pressure plates.

 

Bob.

[Survived-til-now]

I think Stan is closest to what had happened. I am not a mechanic so i am struggling to remember exactly what the dealer showed me in the workshop. The long rod was definitely the the clutch pushrod (I have looked at a Haynes Manual) I think it had welded itself to something at the slave cylinder end but I will ask when I next see the dealer in a few days time. The pressure plate was warped and had to be replaced and so i think was the friction plate. I am not sure but there may have even been a need to replace the cover plate! Incidentally the delaer showed me the old bits and put a straight edge on them to demonstrate the problem - and I trust them when they said the bits were done for.

All I can say is that the bike got very hot in the constant stop start traffic of London in a very hot summer and that I used to leave the bike in gear at lights. Perhaps the real problem was all the stop starting and not the leaving it in gear at lights!