Clutch Stuck Triple - any thoughts please?

On Keith's recommendation, I used Harley Davidson oil. Seems to be pretty good. More expensive than the Morris one above, but it was convenient, as I have an HD dealer 4 miles away.

Pete
 
Looking at the tin the oil is designed for a low revving old vehicle with a dry single plate clutch...

And four wheels.

Isn't the formulation of car and motorcycle oils different given the shearing action of the integral gearbox on motorcycles?
I now use classic Silkolene oils, the motorcycle versions, and the clutch action has always been consistent and free.

Went to the local Classic Bike Club last Thursday, the only bikes that wouldn't leave under their own power were a
GS BMW which required a bump start and a modern Guzzi which required a van.
 
You can bump start a Laverda 3C triple in first gear Cam, I was an expert at it years ago, as soon as the engine turned it fired and you were on your way. Hard work on a winters morning but better than walking.
My clutch stuck so well one time that after getting the bike going on a gradient I had to ride it for about half a mile occasionally standing on the back brake with the clutch pulled in and the throttle held open until the swine freed. it had been stood for a few months as I remember. There is no way you would have freed that by hand.  
 
had to laugh Pat,misread your thread as "better than wanking" then read the end " freed by hand" :D

Shaun
 
Yeah, Laverdas aren't too bad for bump starting. My Ducati is an absolute pain in the arse. I'd hate to have to do a race on it with a LeMans start. I'd never get off the starting line!

I could start my Honda 750 when it was on the centre stand just by turning the back wheel by hand. Not that I ever needed to because the starter button always worked and it also had a kick start. It was just a party trick.
 
Always bump started my RGS in second gear; became quite an expert until I installed a Moto-Witt ignition system. Best mod I ever made to the bike.
 
Dellortoman said:
True enough, you won't spin the engine over as fast in a high gear. But some bikes won't bump start in a low gear. The problem being the torque multiplier effect as explained earlier. If a bike has too much compression, the torque required at the back wheel to turn the motor over will be more than the grip between road and tyre can provide. The wheel will just lock and skid, so you may need a higher gear.
Click to expand...

The same is true in the reverse. It is the practical reason that I wouldn?t try and break the adhesion at the clutch plates by turning the rear wheel in 5th. The engine would give way/turn more easily.  Totally different if the engine has been mechanically locked.




 
Interesting?  ???

Last time I posted that 5th would not be a good gear to try and shear the clutch plates by working on the rear wheel I got this :

Not so Rod. The reason there's less resistance to turning the wheel in a high gear is that the gear ratio is to your advantage. That means you're applying more torque to the engine (and clutch) than in a low gear.

If you don't believe me, do some arithmetic.

I can't remember the actual reduction ratios between engine and rear wheel, but exact numbers don't matter for the purposes of illustration.

Let's say 5:1 reduction in high gear (5,000 rpm at engine gives 1000 rpm at wheel)
The power output is the same (ignoring losses) so what you lose in speed you gain in torque. 100Nm torque at engine = 500Nm at rear wheel.
It also works the other way. Zfor example, applying 50Nm torque by hand to the rear wheel will apply 10Nm torque to the engine.

Now let's assume 10:1 reduction in low gear (5,000 rpm at engine gives 500 rpm at rear wheel)
So 100Nm at engine = 1000Nm at rear wheel. Which we know to be true from experience, it's easier to wheelstand in a lower gear.
However, applying the 10:1 ratio the other way. 50Nm at the rear wheel = 5Nm at the engine. Half of what you had in the higher gear.

The above argument applies equally to the clutch as it does to the engine because they are permanently coupled together via a non-variable reduction.


What all that boils down to is that if you want to use the rear wheel to un-stick the clutch (either by hand or by rolling along the road) get it into a high gear.
Click to expand...

I?m still waiting on some form of reply.on my latest post.  If anyone is going to squash my first advisory post in such a big way then I?d expect some response here, one way or the other.

I really don?t want this to just die away. Either I?m right or wrong but I?m not prepared to be incorrectly corrected without the right to respond.

A simple ? I stand corrected would suffice.  ;)

Cheers

Rod
 
Alpino said:
The same is true in the reverse. It is the practical reason that I wouldn?t try and break the adhesion at the clutch plates by turning the rear wheel in 5th. The engine would give way/turn more easily.  Totally different if the engine has been mechanically locked.
Click to expand...

The reason the engine would give way/turn more easily in 5th is because it was getting more torque applied to it, which was what I was trying to explain.

A simple ? I stand corrected would suffice.
Click to expand...

I'm hardly going to say "I stand corrected" when I'm not incorrect.

Please be assured that there was no personal attack meant by my flippant "Not so Rod" or anything else I wrote. I was just referring to the fact that I didn't get the gearing issue arse-about. If it came across as abrasive or offensive to you then I sincerely apologise.

I'm fortunate in that I've never had a seriously stuck clutch, so I'm not writing about personal experience - only theory, which I'm good at but perhaps don't explain very well.

It was Jon (bsab31) who related his experience of unsticking his clutch by hand in second gear. If he got results in 2nd gear, then that's good. I'm not going to argue with him or say he did it wrong. All he needed was enough force to get the job done.

The point I was trying to get across is that if anyone else finds themself in a similar situation but don't have any luck in first or second gear, try a higher gear. You're absolutely correct Rod, in saying the engine will turn more easily, but you can offset that tendency to some degree taking advantage of the inertia of the crank. Shock loads to the rear wheel as Jon described will do exactly that.

Cheers,
Cam
 
Can't help thinking it would be a hell of a lot easier to pop the primary cover off for a clutch pull and clean.  Fairly easy to do.
 
After thirty years of ownership, never had the clutch stick to such an extent that a bit of rocking back and forth in gear didn't free it up.
I would be inclined to have a peek inside to check things out. IMHO.
 
Poffer said:
Can't help thinking it would be a hell of a lot easier to pop the primary cover off for a clutch pull and clean.  Fairly easy to do.
Click to expand...
I agree it may be easy but you still have to drain the oil, possibly replace the gasket, realign the clutch plates, fix all the other stuff "while you're at it" so I would expect a little  :D or  :P or  :-* somewhere in the text...
 
I?m not miffed, irate or sulking but thanks for the thoughts.  :)

I have had an awful set of stuck plates and I know exactly how hard they are to separate.  :o Pulled them apart twice, tried the cable tie and finally got a new set from Red. Problem fixed.  :D They came that way on th bike wen I bought it. Only had 30+K miles on the clock but had been sitting dormant for years.

I?m sure there are varying degrees of them sticking but I find it hard to imagine there could be many worse than mine were. You could finally get them to break, leave the bike over night and they were as bad, if not worse, the next morning.

I almost dropped the bike a couple of times trying to bump the rear wheel. Mine certainly wouldn?t break by rocking the bike in any gear. Lower gears at least gave the engine better hold if trying to manually turn the rear. I vaguely remember getting this to work a couple of times in lower gears, in higher the engine just turned. Just not able to apply enough shock load. Again, from memory, this was only successful if the bike had only been sitting for a relatively short period of time.

In the end I would start the bike on the centre stand in gear. It would take a combination of revs and rear brake to finally loosen them up. The bike was more than capable of being stalled which I did often. ::)

Anyway, thats my experience with sticky clutch plates. Nothing short of a significant shock load would work.

Rod

 
My clutch became sticky a number of years ago and would really be hard to separate if it was left for say longer than 2 weeks between rides. Originally could separate by rocking bike in gear and sometimes just using revs. After a while the only way to separate them was to get it going* and give it some stick while working the clutch. Usually after a couple of blocks it would give a loud bang and be good as gold (till next time). Unfortunately it just got worse as time went by and new plates were the only answer. Also, I am lucky to live in a rural area so could get bike going and try to free while riding, not recommended with traffic around ;)

(*we also have no nearby hills so was a bit tricky getting goin, no clutch no bump. Used to start up, sit on bike, get rolling (who said you had to be tall) select gear - and be ready for launch :D - could usually match some revs and select gear quite sympathetically )

 
So, Brian, after all this discussion & debate on the various methods/theories to overcome your problem, did you manage to free the clutch?
C'mon, we're all dying to know.
  Regards,Jon.
 
I had one clutch that would regularly seize up solid, even after a few days of non-use.
Rocking it didn't do it, even starting it up and whacking it in gear with the brakes on didn't work, and was too brutal anyway.
In the end I replaced the friction plates with new ones and sanded and cleaned the metal plates.
I blame the Repsol 20/50 oil I was using then. The oil seemed to act as an excellent adhesive between the plates, and it was changed very regularly too. Maybe a combination of wear and decades of accumulated oil additives on the friction material.
 
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