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Shifting from 4th to 5th in MT

jms_w2010-08-29 17:49:36 +0000 #1
So, being fairly new to a manual, I'm having a hard time shifting from 4th to 5th without the rear bucking. Trying to conserve fuel, I'm shifting between 2600 and 2900. I'm fine for the lower gears as I'm holding the clutch pedal in for just a moment after shifting before pulling up on the clutch pedal, but for the shift from 4th to 5th, I feel like I have to keep the clutch pedal in for a couple of moments longer or else I get the buck and even then it's hit or miss. The RPM's drop so fast when the clutch pedal is down that I can't shift fast enough. Am I supposed to be on the gas a little before letting the clutch out or should I not push the clutch pedal all the way down? How do you guys/gals shift? Am I shifting way too early for 5th?
srobmw2010-08-29 18:06:10 +0000 #2
IMHO you're shifting at too low an RPM. Try it at 4000+ RPMs. I think you'll find it much smoother.
330CIZHP2010-08-29 18:12:15 +0000 #3
That is result of the low-mass inertia of the flywheel. The car has a very light flywheel in order to allow fastest access to redline. Since the purpose of the flywheel is to store energy so that the car can easily get off the line, lighter flywheel trades the smoothness and ease of getting off the line without much throttle input for exceptional response and ability to rev.

Personally, that is the beauty and fun of driving a manual transmission. The quirkiness. It is an art form that requires mastering differently for different cars. Give it time and you will see it will become second nature to you as you will develop a way yourself to shift smoothly.

The daily driving gets a little tricky with a very light flywheel. A way to handle this (takes some practice) is to quickly blip the gas a bit before releasing the clutch. It is a delicate balance that takes some practice.
ersin2010-08-29 18:01:46 +0000 #4
Quote:

Originally Posted by jms_w

Trying to conserve fuel, I'm shifting between 2600 and 2900.

Shift 3000+ rpm.

Quote:

Originally Posted by jms_w

...Am I supposed to be on the gas a little before letting the clutch out ...

Yes. Takes practice but try to match revs, it'll be a little lower than when in 4th.

Quote:

Originally Posted by jms_w

... or should I not push the clutch pedal all the way down?

Push it all the way down.

Quote:

Originally Posted by jms_w

How do you guys/gals shift? Am I shifting way too early for 5th?

Shift at a higher rpm. It's a little trickier but you'll get the hang of it the more you do it. Up or downshifting, try to make it smooth by matching revs. Again, it takes practice. But when you do it perfect it's as good as sex.

Cheers.
smmmurf2010-08-29 18:05:35 +0000 #5
You should shift at a higher RPM (~3,500-4,000).
chris7192010-08-29 19:08:21 +0000 #6
Shifting more quickly can help also, it's a problem into 5th because of the longer throw. Try backhanding the shift knob and it will make it faster.
jms_w2010-08-29 18:11:03 +0000 #7
Thank You all for your advice. It sounds weird to rev match on upshifts as I've only heard it done on downshifts but I'll give that a shot. But question about rev matching, I know it's down while clutch pedal is down but do I blip the throttle while in 4th gear, neutral, or 5th gear before I let the clutch out? I can never figure this out.
iBeJayKaying2010-08-29 18:42:28 +0000 #8
Try watching these, he's pretty good at teaching, I thought.

Video From YouTube:(link)


Video From YouTube:(link)


If you're bucking going 4th-->5th, then chances are you're most likely shifting too early. Like most people have said in this thread, try shifting at higher RPM's, like 3,500+. Rather than getting used to rev matching during upshifts, you should just get used to doing it correctly. Bad habits are easy to make and hard to break, after all.
Finnegan2010-08-29 18:56:51 +0000 #9
Quote:

Originally Posted by jms_w

Thank You all for your advice. It sounds weird to rev match on upshifts as I've only heard it done on downshifts but I'll give that a shot. But question about rev matching, I know it's down while clutch pedal is down but do I blip the throttle while in 4th gear, neutral, or 5th gear before I let the clutch out? I can never figure this out.

Shifting at higher revs does help, but it's not required. In city driving especially it's perfectly okay, and at times more reasonable for conditions to shift at lower RPMs.

Mind you, shifting at higher revs is probably the most practical answer.

But IMO one should be able to shift smoothly in various modes/conditions across the rev band.

Here's "my" method--the thing is to try several things and find what works best for you and your style.

Just keep your foot a bit on the throttle and don't lift all the way off. Keep some pressure on it, and if done correctly the revs will be at just the right level (just above where they'll end up when you let off into the next gear). It's not so much a "blip" (but okay to think of it as such as if it helps) as much as "don't let the rev fall to fast" exercise. You're just trying to keep the revs from falling too fast too far (e.g., let them drop from 3K to 2K, not to 1.5K). Even shifting at higher RPMs without doing this in some cars will result in a lack of a smooth shift (the Z4M being one of those, especially 1st to 2nd).

Think of the having an egg between your foot and the throttle--you don't want to let the egg roll off onto the floor. (Have to give credit to my wife on that one--she's the master of all things shifting on the Z4M, which makes shifting the M3 seem like a breeze in comparison....)

The "blip" is more of a downshift thing, there you need to actually get the revs up past where they were (e.g. 3K to 4K).

Quote:

Originally Posted by chris719

Shifting more quickly can help also, it's a problem into 5th because of the longer throw. Try backhanding the shift knob and it will make it faster.

This is one way to do it; same end effect as the method I noted.

Quote:

Originally Posted by 330CIZHP

Personally, that is the beauty and fun of driving a manual transmission. The quirkiness. It is an art form that requires mastering differently for different cars. Give it time and you will see it will become second nature to you as you will develop a way yourself to shift smoothly.

Yep, one thing that makes driving more fun!

I like my DCT, but miss my 6MT.

Every now and then I get to borrow the ///M (which is very hard to master) and find that thrill again!

Quote:

Originally Posted by iBeJayKaying

Try watching these, he's pretty good at teaching, I thought.

Video From YouTube:(link)


Video From YouTube:(link)


Bad habits are easy to make and hard to break, after all.

You've got a heck of a good point there! It's taken me a long time to stop fully "lifting" off the throttle on upshifts.

Bad habits die hard.
330CIZHP2010-08-29 19:48:19 +0000 #10
It is only to bounce the revs back up a bit so that the flywheel can spin a little faster in order to make it smoother.

Anyway, people have been recommending shifting at higher rpms, which is probably a better solution.

Quote:

Originally Posted by jms_w

Thank You all for your advice. It sounds weird to rev match on upshifts as I've only heard it done on downshifts but I'll give that a shot. But question about rev matching, I know it's down while clutch pedal is down but do I blip the throttle while in 4th gear, neutral, or 5th gear before I let the clutch out? I can never figure this out.
Finnegan2010-08-29 21:38:33 +0000 #11
Quote:

Originally Posted by 330CIZHP

It is only to bounce the revs back up a bit so that the flywheel can spin a little faster in order to make it smoother.

Anyway, people have been recommending shifting at higher rpms, which is probably a better solution.

Agreed, easiest and fastest way to cure.
330CIZHP2010-08-29 21:47:57 +0000 #12
Quote:

Originally Posted by Finnegan

Agreed, easiest and fastest way to cure.

Yes, that is a very effective trick. Do not lift foot toe entirely off the gas pedal while shifting. Stop when there is 10 - 15% travel left using light toe weight that will complete the throttle from being fully closed, which means the flywheel will lose speed slower.

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