Shifting without using the clutch

[Daox]

Originally Posted by Ryland

Why would you bother? compare the cost of replacing the tranny to the cost of a clutch, if you get good at it, and still use the clutch then both the tranny and the clutch should last 1,000,000 miles.

Ditto. I work in the gearing industry. We go to great pains to grind gears to an incredibly high precision to provide maximum torque capacities out of these kind of things. Of course there is a saftey factor built into everything so you can get away with it. But, as Ryland said, why do it when there is a perfectly capable system already in place to do it better?

[elhigh]

I discovered this years ago by accident, but I don't do it.

You'll burn out the syncroes. It's a lot cheaper to replace the clutch than it is to crack open the tranny and replace them.

[RH77]

So, will the electric DeLorean go 88 MPH?

I agree with the clutch issue -- use it.

RH77

[jazzie604]

Originally Posted by dcb

I don't use the clutch on the motorcycle to upshift, except to get going. It is smoother that way when done right, basically a quick forward twist of the wrist to slacken the drivetrain and a lift of the toe at almost the same time, takes maybe 1/10th of a second before I'm back on the gas.

Occasionally I do it it a car, not usually though, seems to take to long and my momentum gets wasted. I know the big rig drivers dont use the clutch to shift.

I think most bikes have "dog" cut gears, and are designed to be shifted with out the clutch. Cars are designed to be shifted with the clutch and, on most vehicles, you will quickly wear the synchros out. Some makes (Hondas especially) will shift without the clutch well, but thats a rarity instead of a standard. I wouldnt do unless you are ready to rebuild a tranny soon.

[LostCause]

Originally Posted by RH77

So, will the electric DeLorean go 88 MPH?

Ya, but it needs 1.21 Gigawatts of power...

Originally Posted by jazzie604

I think most bikes have "dog" cut gears, and are designed to be shifted with out the clutch. Cars are designed to be shifted with the clutch...

I believe all manual transmissions use dog teeth since shifting is done by engaging a gear through sliding collars splined to an input/output shaft.

All manual transmissions (that I know of) are designed to be used with a clutch. Motorcycle transmissions usually don't use synchros, so technically the driver must double clutch when deccelerating. I don't know why motorcycle transmissions are more forgiving, but since double-clutching is a pain, most just shift higher gears clutchless (which increases wear).

- LostCause

[trebuchet03]

So I've figured out how to get 4th and 5th.... 4th is a slow shift - 5th is a super fast extra firm shift (the difference in rpms is 500). Can't quite figure out third - and I won't try second until I get third

I'm not looking to just stop using my clutch - I figure it's a good skill to know in the event a hydraulic component decides to crap out on me

One thing I noticed.... If I slightly miss - then hit the clutch and continue with the shift - the dogs don't mesh. They continue to interfere and I can't get into gear until I pull back near neutral and retry.

[basjoos]

This technique is easiest to do in an older car with a sloppy, worn-out gearbox, which is precisely the type of car which is more likely to experience a clutch cable, hydraulics, or arm failure.

[diesel_john]

my trucker shifts without a clutch. I watch. non-synchronized tranny's work best for this. separates the men from the boys.

[boxchain]

OK, thanks for all the info and free internet advice!

I agree that the clutch is a wear item and synchros aren't. I'm not recommending it as a daily practice, but it's why I can still drive my truck so it's good to know just in case.

This has nothing to do with FE...although everything affects FE, it would be hard to find it in a test.

Hondas do this very smoothly...if I grind it's surprising. My truck is RWD and has a long throw shifter, so it's harder. Takes longer too, prob the large flywheel. OT, the Honda is easier to bump start too. :hmm:

It's much harder in the lower gears since you want the revs to drop at a very low rate. I basically save this technique for the higher gears, when I'm at cruising speed, not accelerating.

It does save fatigue. All of the driving that I do involves nothing but accelerating and decelerating. I often don't make it into 4/5 with a more than one traffic light per mile.

OK, does anyone use the clutch to come out of gear? Coz I never do that

[zjrog]

I used to, until it killed the synchor in the Neon... With only 20,000 miles on it! Lucky me though, when the dealer tore down the transaxle (under warranty at the time!!!), the diff pin was about to slide out. One new transaxle later, and I have 50,000 miles on the replacement.