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Samirr76
05-21-2001, 03:19 PM
Bad idea to use the clutch to maintain position on a *slight* hill at a traffic light forexample today, no foot on the gas, sightly let out the clutch halfway and the car doesnt roll back anymore. WIll I wear out the clutch much faster doing this or is the wear negligible when slipping while the engine is idle?

tmat3
05-21-2001, 03:33 PM
Very bad for your clutch. Don't do it.

The only time you're rally supposed to step on the clutch is:
1) shifting
2) Starting engine

Also, by stepping on clutch while you're at a red light can wear out the throw out bearing.

So, if you're stopped at red light or any other places, use neutral and step on brake.

ColinL
05-21-2001, 03:48 PM
what most people also fail to realize is that holding the clutch in while idling, or riding the clutch to stay in place on a hill places a whole bunch of stress on the mainbearings. the crankshaft is violently accelerated during a power stroke, and decelerates at all other times. the flywheel keeps things spinning at a reasonably smooth rate so that the main bearings are longer-lived. it can't do this very well when trying to spin the clutch and layshaft, or when the entire car is loaded against it at low RPM.

anyway, don't get into the habit. riding it briefly to hold a hill before accelerating is normal. trying to be cute and doing it through a stoplight is just stupid. keeping the clutch down through a stoplight, in gear or not, is also stupid.

Samirr76
05-21-2001, 05:12 PM
So I should always be in neutral at a stoplight? Can't leave it in 1st and hold the clutch all the way down or is that bad for the throwout bearing too? Just verifying what you've all said....

grimlock
05-21-2001, 05:14 PM
My general rule is that, if I know I'm going to be stopped at a light for more than 10-15 seconds, I throw it in neutral and give the TO bearing a break.

ColinL
05-21-2001, 05:23 PM
grimlock kick butt. http://www.i-club.com/ubb-files/smilies/biggrin.gif

anyway, this is all just best practice. in reality many other things will affect main bearing, clutch and general powertrain longevity a lot more than holding the clutch in during while stopped will.

my first reply explained it all though. it's BEST not to keep the clutch down if you're stopped for any length of time.

Star*Child
05-21-2001, 05:36 PM
Once upon a time, I knew this guy who had a toyota truck. He thought he would use the clutch to hold his position on hill at stoplights. In Seattle.

I told him... I TOLD him...over and over. I said, "use your e-brake to not roll backwards. It works, you'll learn and it's easy!"

"no...it's cool this way," he said.

clutch lifetime on his 1 year old truck?


3 weeks


Don't do it

Samirr76
05-21-2001, 05:44 PM
Thanks guys hope those qestions werent too dumb but this is my first stick shift vehicle. I sppreciate the advice so i dont ruin my car prematurely. One last question... how critical is it to mtch rpm's between shifts becxause I am having a hard time mastering that. Really hard time...

Xio
05-21-2001, 06:31 PM
By matching rpms you are making life easier for your synchros. When upshifting (1 > 2, 4 > 5 etc.) rev matching occurs naturally because the engine rpms fall when you press the clutch. Smooth upshifting is a simple matter of reengaging the clutch precisely as your rpms fall to the "sweet spot" where they match the driveshaft rpm. You will know this "sweet spot" because when you clutch out, it will be smooth as glass, less vibration than an automatic tranny shifting.
Downshifting (4 > 3, 3 > 2etc.) is a different manner. Here, the engine rpms must *rise* in order to match the layshaft rpm dictated by the new lower gear ratio. In order to get the revs to match you must blip the throttle to raise the engine rpms. I am currently in the process of teaching my wife to do this. Here's my method:
First, learn to blip throttle. Get going in 4th gear then let off the gas and let the car decelerate till it reaches 2500 rpms. At this point you will shift to 3rd gear. Clutch in, then stab the gas pedal hard with your right foot so the rpms rise to 4000. They will begin to fall again, so reengage the clutch around 3500. What should happen when you do this right is that your car will continue to coast, the revs come up, and you reengage the clutch in 3rd gear as the revs match the required rpm dictated by your current road speed and the 3rd gear ratio. This means that reengagement will be smooth and the car will not become unsettled. Most beginners tend to ignore blipping the throttle which causes massive deceleration (engine braking) and nose dive. Blip throttle rev matching keeps the car level. What happens when you do it wrong is alot of herky-jerkiness and it's not good. http://www.i-club.com/ubb-files/smilies/wink.gif
Second step is double clutching. It's basically the same, except it involves more stages. Clutch in, shift to neutral, clutch out, blip throttle, clutch in, shift to new gear, clutch out. I usually drive this way as this method saves my synchros from doing most of their job. Instead of the synchros working to accelerate/decelerate the layshaft to match, I am doing their work by adjusting the layshaft with the engine. An additional benefit is that it keeps the car settled for fast corner exits. http://www.i-club.com/ubb-files/smilies/smile.gif
Third step: Heel and toe. I probably won't ever get around to teaching the wife this, because I can *barely* do this myself. Most of the time I screw it up and I don't like the sounds the tranny makes when I do, so I don't try it much. http://www.i-club.com/ubb-files/smilies/wink.gif
Hope that helps.

[This message has been edited by Xio (edited May 21, 2001).]