Posted by Brian in Oregon on May 29, 2000 at 18:24:27:
In Reply to: Double clutching posted by In need of info on May 29, 2000 at 18:04:53:
Double clutching is the practice of disengaging a clutch by:
1. Depressing the pedal.
2. Pulling the shift lever out of gear into neutral.
3. Releasing the clutch pedal.
4. Pushing the clutch pedal back in.
5. Shifting into the desired higher or lower gear.
6. Releasing the clutch pedal.
You'll note that a modern fully syncho'd tranny skips steps 3 & 4. This is because the tranny has synchronising gears to spin up the other gear clusters. When you double clutch, you are manually spinning up the gears. Many older transmissions were either non-synchro, or were lacking synchro on 1st and sometimes 2nd gear.
It is possible at times to shift a non-synchro tranny without double clutching, but there are several variables at play, such as road speed, what gear you are in and going to, and engine speed. Some people who are very familiar with their vehicles can do this (assumming the vehicle is one of those you can get away with it on), but most folks will only grind the gears, getting shavings and metal particles into the bearings. It takes some getting used to when all you've driven is synchro'd trannys, so it is best to learn in light traffic and stay off of steephills until you get good at it.