Downshifting: when has slipping the clutch gone too far?

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Re: Downshifting: when has slipping the clutch gone too far?

Post by Rope-Pusher » Mon Oct 08, 2018 10:21 pm

Rob, Rob, Rob,

No, No, No!

No wonder the nubes never stick around anymore - You handled that all wrong.

You should have handled it like the French would have.

Here he is, just got off the boat, and there you go telling him his post was full of nonsense. Now he's got nothing to do but feel bad for himself, like he did something stupid and doesn't belong here.

Instead of putting the guy down by referring to his post as a bunch of nonsense, you should have drawn attention to it being nonsense, but also expressed pity that he was full of nonsense through no fault of his own, that he must not have had any smart friends, teachers, or mentors to steer him away from that nonsense. See, you acknowledge his faults, but you lay the blame on his environment. Then you could have added something like "Stick around here Nube, and your likely to learn something". That's how the French would do it, and 33.5 million Frenchmen can't be wrong, right?
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Re: Downshifting: when has slipping the clutch gone too far?

Post by theholycow » Thu Nov 01, 2018 4:07 pm

ClutchFork wrote:
Sun Oct 07, 2018 10:03 pm
Ok the other thing about down shifting is go gently in wet conditions and perhaps DON'T DO IT IN THE SNOW. I once downshifted gently on road that had a half inch of snow (I-96 in morning rush) and my Ranger instantly turned sideways. Thankfully, nobody was in the next lane by me because my tail end went into the next lane.
I would generalize that into this:

Always be sure of how much traction you have, and know how much you're about to use when you do anything. Always leave some margin.

That statement covers fast clutch foot as well as the common question about shifting during a turn. If you're at the edge of traction (which, in an unloaded 2wd compact pickup with all-season tires on wet or snowy roads, is pretty much always) then you can't get away with anything. OTOH if you have traction to spare (which should be ALWAYS unless you're on a closed course) then a little rough clutchwork isn't going to be a problem.
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Re: Downshifting: when has slipping the clutch gone too far?

Post by Rope-Pusher » Thu Nov 01, 2018 9:39 pm

Yeah, what the cow mooed, er, what the cow said.

Yanno, the brake pedal is connected to 4 wheels and the clutch pedal mostly just to 2 wheels,
[youtube]https://www.youtube.com/watch?v=6dq3sGHrMcw[/youtube]
so it stands to raisin that "When the frost in on the punkin, that's not the time for clutch pedal flunkin."
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Re: Downshifting: when has slipping the clutch gone too far?

Post by Shadow » Tue Nov 06, 2018 9:08 am

childoffire wrote:
Sat Oct 06, 2018 3:27 pm

Your comment is chock full of assumptions and personal opinions but few facts.

#1: "Riding the clutch damages it"
How do you know your friend had to get his clutch replaced BECAUSE he was riding the clutch? Could it not have been something else? Had you been with him on every drive he ever went on?
I doubt that!

I've been driving the same car for the past 10 years now and I always press the clutch when braking. And I still haven't replaced my clutch, nor do I see any replacements coming up any time soon!

If you'd ask any mechanic, the most common reason for clutch damage is engine lugging, i.e, forcing the engine to pick the car up at low speeds in higher gears. Other reasons include (but aren't limited to): not fully pressing the clutch during shifts, not letting off the gas during upshifts, incorrect rev matching during downshifts, or simply an excessively tight clutch cable.

And this makes sense, because the clutch will be damaged only when there is friction between it and the flywheel (or between the clutch plates in the case of motorcycles), not by pressing the clutch pedal that can only put strain on the clutch springs and nothing else.

So no, riding the clutch can NEVER damage it.

#2: "Slow downshifts damage the clutch"
That's just ridiculous.

If you had two disks rotating at different speeds and you were asked to bring them in contact, what will you do?
Would you just slam them against each other? Or would you allow them to slowly come into contact so that they can match speeds?

Which technique will cause more damage to the disks? The slower one? Seriously?

#3: "Incorrect rev matching is not a big deal!"
I really feel like explaining this to a kid at this point.

How can you even think that slow downshifts cause clutch damage but incorrect rev matches are "not a big deal"?

Going back to the disk analogy again (it's actually not even an analogy... that's exactly how the clutch works!), suppose you were asked to bring the rotating disks in contact but now you were asked to slam them against each other, what will you do to reduce the damage?

Simple. You'll TRY to eliminate the speed difference between the two.

How will you do that?

You'll try to slow the faster one down and speed the slower one up before slamming them against each other.

This is exactly what you're doing when you blip the gas and apply brakes at the same time.

But is it okay if you do it incorrectly?

NOT A CHANCE.

An incorrect blip would not be much better than no blip at all. So it's better if you just eased the clutch out slowly.

And if you still think the attitude your car shows when you blip too high or too low is just quirky behavior, then trust me, you're the one who's soon going to need a new clutch!!!
Wow, I wish I would've read this back when it was posted. I don't know if this guy is trolling (one post like this and he's gone) or if he's just completely ignorant, but almost everything he said is incorrect.

Engine lugging causes clutch damage? Largely incorrect.

Riding the clutch can NEVER damage it? Completely incorrect. Unless he somehow doesn't equate damage with excessive wear.

"If you had two disks rotating at different speeds and you were asked to bring them in contact, what will you do?
Would you just slam them against each other? Or would you allow them to slowly come into contact so that they can match speeds?" --- Too fast or too slow, neither is good. The idea is to use the clutch to get those "two disks rotating" the same speed with as little wear as possible. Again, too fast or too slow is not good.

:How can you even think that slow downshifts cause clutch damage but incorrect rev matches are "not a big deal"?" --- Incorrect rev matches in the manner described, really mean that the driver attempted to rev the engine to the correct RPM before downshifting, but didn't precisely hit the exact RPM to allow for no clutch slippage. Even an expert driver doesn't nail it every time. That said, in this context, an incorrect rev match really isn't a big deal. It's minimal clutch wear in the grand scheme of things.

I could go on, but I won't. This post was made about a month ago and it seems that the guy is gone anyway.
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Re: Downshifting: when has slipping the clutch gone too far?

Post by Shadow » Tue Nov 06, 2018 4:45 pm

ClutchFork wrote:
Mon Oct 08, 2018 12:55 am
Here ya go. Auto-rev-match-downshifting on the 2019 Mustang. (No thanks, I'll keep my 1992 Mustang)

https://www.youtube.com/watch?v=rh_7N3j ... e=youtu.be
Quite a few cars have automatic rev matching (downshifting and upshifting) and I don't necessarily think it's a bad thing. Why? Well, for one, I'm pretty sure it can be turned off on most, if not all cars. Secondly, it's not a bad thing for noobs who haven't yet developed the skill themselves. And lastly, it's good for the car manufacturers who have to warranty their vehicles. For sure this technology helps there.

But for me, I'd just as soon turn it off because a perfectly executed rev-matched downshift is one of the most satisfying things about driving a manual transmission car.
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