Manual transmission Clutch Question...

[mechman600]

Originally Posted by sarguy01

So, under some of these circumstances, would you not agree that a good clutch can slip?

No. Like P-Hack said, a slipping clutch is a broken clutch. Or an incorrectly sized clutch for the desired application.

If clutches did slip (even a little), you would be able to see it on the tachometer when it did. But you never ever do.

[sarguy01]

Originally Posted by mechman600

No. Like P-Hack said, a slipping clutch is a broken clutch. Or an incorrectly sized clutch for the desired application.

If clutches did slip (even a little), you would be able to see it on the tachometer when it did. But you never ever do.

Really? A little slip? Let's define slip. Anytime the clutch is engaged but cannot hold the engine's torque. A clutch slip scan be the smallest slip (1/100000....0th of a rotation compared to the flywheel) all the way out the very obvious failing clutch slip everyone is referencing.

You would be able to tell if your clutch slipped 1/10th of a rotation by looking at the tachometer? We are talking about less than 1/100th of a second at 2000 rpm.

That is 2000 revolutions per minute, 33.33 revs/sec, 3.33...3 revs/10th sec, .3333 revs/100th sec, and so on.

[poomanchu]

This is still going?

[mikeyjd]

Originally Posted by sarguy01

Really? A little slip? Let's define slip. Anytime the clutch is engaged but cannot hold the engine's torque. A clutch slip scan be the smallest slip (1/100000....0th of a rotation compared to the flywheel) all the way out the very obvious failing clutch slip everyone is referencing.

You would be able to tell if your clutch slipped 1/10th of a rotation by looking at the tachometer? We are talking about less than 1/100th of a second at 2000 rpm.

That is 2000 revolutions per minute, 33.33 revs/sec, 3.33...3 revs/10th sec, .3333 revs/100th sec, and so on.

So you're talking about the teardrop in the ocean scenario. Two questions: Does it matter? Could you ever tell conclusively either way? If not then your argument has, in effect, no meaning.

[sarguy01]

Originally Posted by mikeyjd

So you're talking about the teardrop in the ocean scenario. Two questions: Does it matter? Could you ever tell conclusively either way? If not then your argument has, in effect, no meaning.

If my argument has no meaning, why are you posting?

[mikeyjd]

Originally Posted by sarguy01

If my argument has no meaning, why are you posting?

To point that fact out to you.

[P-hack]

Yes, you can conclusively tell, you can make a "slip gauge", basically you need a position sensor on an output shaft and the crankshaft position sensor, need to know the precise gear ratios in the trans, and you can keep track of that stuff with a microcontroller and an LED or LCD display, etc. Display the last "slip" and how many crankshaft degrees it was and how long ago it was. Have fun

[sarguy01]

Originally Posted by mikeyjd

To point that fact out to you.

Thanks.

This is a public forum. I am allowed to post anything according to the rules. If I want to present an argument, no matter how small, I get to do it. One use of a public forum is that it is place for feedback for thoughts (and it is fun to present arguments). That does not mean you need to post something. I don't really care that you posted, but your posts had nothing to do with my tiny argument.

You mentioned a "teardrop in the ocean". Yep, but when ecomodding we look for teardrops everywhere to improve our overall mpg over time. Teardrops add up.

Plus, if this argument is meaningless, why are there three pages of posts??

[sarguy01]

Originally Posted by P-hack

Yes, you can conclusively tell, you can make a "slip gauge", basically you need a position sensor on an output shaft and the crankshaft position sensor, need to know the precise gear ratios in the trans, and you can keep track of that stuff with a microcontroller and an LED or LCD display, etc. Display the last "slip" and how many crankshaft degrees it was and how long ago it was. Have fun

I wish I had the time to put something like that together. It'd be purely for my own entertainment though.

[redpoint5]

Originally Posted by sarguy01

Really? A little slip? Let's define slip. Anytime the clutch is engaged but cannot hold the engine's torque. A clutch slip scan be the smallest slip (1/100000....0th of a rotation compared to the flywheel) all the way out the very obvious failing clutch slip everyone is referencing.

You would be able to tell if your clutch slipped 1/10th of a rotation by looking at the tachometer? We are talking about less than 1/100th of a second at 2000 rpm.

That is 2000 revolutions per minute, 33.33 revs/sec, 3.33...3 revs/10th sec, .3333 revs/100th sec, and so on.

I would say you are correct if you define slip as any relative motion whatsoever. The clutch "slips" just as your car "slips" while parked in a parking lot. After all, it is only friction that is keeping it from moving.

A properly functioning clutch would probably only slip your 1/10th of a rotation over the lifetime of the vehicle. Again, it would be like measuring how far your car has moved since you parked it. Or put another way, how far does your car move when you apply the brakes fully? The friction of the brake is the only thing preventing the car from moving.

I bought a Subaru Legacy that had a barely perceptible slip when mashing on the throttle. Within a month, that small slip caused it to wear very rapidly and then completely fail to move the vehicle with even the slightest amount of throttle.

I hate to say it, but I'd say it was an incorrect statement on your part. It would be like me appearing in court to defend myself against an assault charge and my defense being "my fist never actually hit the mans face; the electrons in my hand just got close enough that they violently repelled the electrons in his jaw".