What about shifting from 4th or 5th to neutral when coming to a stop. Any issues there?

 

You do not need to double clutch when you skip a shift.........
What you do need to do though is not rush into the next gear, you have to spend a bit more time waiting before you put the gear lever into that next gate
That waiting is exactly what is needed
The irony here is, people who are double clutching are doing just that, waiting, spending more time between gears
And then, they make a wrong conclusion, like it's the double clutching that made the difference, when in fact, it was just the wait
My 1957 MGA does require double clutching to downshift into 1, and sometimes 2, but the modern S does not need it going up, or down

 

I coast into a stop all the time in the truck, the whole downshifting thing is not all that rewarding in the truck, and brakes are much less money than transmissions and clutches, and, honestly, that coasting in can do amazing things to increase the fuel economy. Do I do the same thing with the S? No. But the method of coasting in is not some evil thing.

Oh, and for that "god forbid" situation you mentioned, no biog deal, if someone knows how to shift and is good at rev matching then that is all the situation requires. This in fact happens a lot when coasting in, I'll come out of 6th and be coasting in, and then as I get up to the light it will turn green, simple, slide it into 2nd or 3rd, match the revs, let out the clutch, and carry on, no big deal...

 

this was my question and someone elses that no one really clarified on.

I do this quite often.. is there a problem with this? should i run my shifts down in order with the clutch pedal down? thanks

 

Here's a thread had bookmarked on the topic:

https://www.s2ki.com/s2000/topic/448...-rev-matching/

The conclusion was basically if you're going to skip gears, either double-clutch (for a downshift) or row through the skipped gear(s) while the clutch is in (for an upshift). I don't normally skip gears but when I do, I follow the advice from that thread. I'm not trying to give advice as I'm not qualified to, but just providing a link in case you find it helpful.

 

this was my question and someone elses that no one really clarified on.

I do this quite often.. is there a problem with this? should i run my shifts down in order with the clutch pedal down? thanks
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It is extremely poor practice to coast up to stops. The clutch should be engaged all the times except briefly when changing gears (whether skipping gears or not). Get in the habit of doing keeping the clutch engaged and downshifting (being able to match revs and heel/toe will allow you to downshift from higher revs, otherwise you have to wait until your pretty slow for the gear you're in) while slowing/stopping.

 

No need for double-clutching on downshifts or rowing through the skipped gear(s) on upshifts. If you need to do this to execute the shift cleanly, work on your technique and consider whether skipping gears is really appropriate in situations where they don't come off easily.

 

I always run it through each gear, even if I don't let the clutch out for every gear, partly to go easy on the synchros, partly to keep my own rhythm in sync as I set up for corners and rev-match, and partly because I have found I am less likely to select the wrong gear if I do them in order.

 

Some of you guys act like we're driving either cars from the 1930s or full-fledged sequential shift race cars. "Extremely poor practice" is pretty strong. If everyone took this to heed on every deceleration/stop, you'd have a lot more people/inexperienced drivers burning their clutches and over-revving from downshifting improperly, or getting into accidents because they're trying to shift down through every gear.

 

Quoted directly from the thread in the link.




This issue with skipping gears has to do with the inertia carried through the transmission by the input shaft (and clutch disc). Rev matching has nothing to do with input shaft RPM, and does not help. The only exception to this is if you double-clutch in-between the skipped gears.

When rev matching, you're only matching the engine RPM (roughly) to the throughput of the transmission's output shaft - through the selected gear (based on your car's speed).
However, rev matching does not slow the input shaft or account for excessive input shaft RPMs - for the gear being selected. It takes time for the input shaft to slow to a reasonable (and not damaging) speed, if you do not shift through all gears, or double-clutch.

As I've stated above, there are only two ways to slow down the input shaft without causing undue stress on synchros: correct sequential shifting (row through every gear - letting successive synchros do their job), and double-clutching (using the engine to slow the input shaft while the transmission is in neutral). Well , three if you are willing to wait several seconds for the input shaft to slow between shifts (internal friction).





Knowing this, why would anyone even take a chance on skip shifting frequently. I like the analogy with the sailboat, but it does not relate in this situation at all. If you want to keep trying fate with the gearbox, and skipping it by just waiting, keep doing it. I rather just save my tranny and hit every gear.