hill start rpms and clutch life

[AHTOXA]

In all seriousness, since you are concerned about the clutch life, preventative measures like the handbrake method are much better options for you.

[StickIt]

Can someone explain in some more detail how using the handbrake to launch on hills causes less clutch wear? I actually want to learn the handbrake launch anyways but am wondering why it causes less clutch wear.

[AHTOXA]

Can someone explain in some more detail how using the handbrake to launch on hills causes less clutch wear? I actually want to learn the handbrake launch anyways but am wondering why it causes less clutch wear.

It causes less wear because you can launch at lower RPM with less clutch slippage. I.E., If the hill is severe enough and you are not using the handbrake, then you will roll back a little bit. Once this is happening, your clutch has to overcome the backwards momentum and also get your car moving forward. This requires a bit more torque exerted on the clutch to get the car moving.

When you launch off the handbrake, your car is not rolling back, you just start moving forward w/o having to compensate for the rollback first.

[StickIt]

Can someone explain in some more detail how using the handbrake to launch on hills causes less clutch wear? I actually want to learn the handbrake launch anyways but am wondering why it causes less clutch wear.

It causes less wear because you can launch at lower RPM with less clutch slippage. I.E., If the hill is severe enough and you are not using the handbrake, then you will roll back a little bit. Once this is happening, your clutch has to overcome the backwards momentum and also get your car moving forward. This requires a bit more torque exerted on the clutch to get the car moving.

When you launch off the handbrake, your car is not rolling back, you just start moving forward w/o having to compensate for the rollback first.

Ok, this kind of ties into another question I've been meaning to ask: Won't the car stop rolling back if the clutch starts engaging? Furthermore, will the clutch alone be able to hold the car on any hill no matter how steep or does it matter how much torque your engine produces at idle?

[AHTOXA]

As the clutch start engaging, it has to over come the momentum with which the car starts rolling backwards. This requires additional slippage that I was talking about, causing more wear.

Your average vehicle does not produce much torque at idle to hold you on a hill. Maybe a very small one. Keep in mind, that this is not recommended because in this case the clutch is constantly slipping, heating it up and causing extra wear. Do not hold your car on a hill with the clutch, even if you're not adding gas. Use the foot brake or the handbrake. Handbrake is the recommended method but I only find myself using it on steeper hills where I might roll back more than a couple of inches.

[StickIt]

Yeah, I had a minor brain fart about the car rolling backwards. I guess the faster you can engage the clutch the less the car will roll backwards, but it will roll backwards nonetheless. On my car I have what is called "hill assist" that keeps the brakes applied for 2 seconds after releasing the foot brake so I was confusing things.

Regarding not holding a car on the hill with a clutch, yeah, I know not to do that, I've read hundreds of threads on here and seen that mentioned many times . I was asking more just to satisfy my curiosity because a few weeks ago when I had someone helping me try to learn how to launch on hills he made me take my foot off the brake and without applying any gas engage the clutch to show me that the car wouldn't roll backwards. What I'm trying to understand (again, not that I am going to do this) is would I be able to do this clutch hold on a hill of any grade? If not, what is the limiting factor here.

[AHTOXA]

Not on any grade, no. Depending on engine torque the grade will vary. Eventually it will be too steep and the force of the rolling car's mass will be greater than torque of the car in idle. You can add more gas and still stay there, then it will hold.

As you know, that will kill the clutch.

[PILL]

The handbrake is useful. I'm going to start with that and stop with that here. You need to develop a reliable technique, handbrake or not, that will allow you to safely and quickly ascend hills without overly wearing your car's components.

Practice is boring but worth it. I would start on slight inclines and graduate your way to steeper and steeper inclines. But like any form of practice, it won't perfectly mimic real life situations, and you'll have to learn to adjust to that. It will all come with time but if ingrain the right habits then it will come more easily and more quickly.

Eventually there will come a time during the day when you're sitting stopped on a steep incline, the nose of the car behind you is barely kissing your rear bumper, and you cannot see the light change for the road perpenicular to you. You'll give up waiting in gear with the clutch disengaged because you're leg is tiring and you can't help but feel sad for your throw out bearing. The instant you engage the clutch in neutral, the light turns green, and the car behind you immediately honks, you can't afford to roll back, and you'd prefer not to overly slip the clutch. Practice will make moments like this worry free and easy to do, so long as you develop a technique with which you can feel comfortable.



Good luck, let us know if you have any more questions.

Just remember, that jackass behind you doesn't matter. Take as long as you need to safely get moving without putting undue wear on your vehicle.

His horn is just his way of saying "Move it! I need to drive fast to make up for my small penis."

[StickIt]

Not on any grade, no. Depending on engine torque the grade will vary. Eventually it will be too steep and the force of the rolling car's mass will be greater than torque of the car in idle. You can add more gas and still stay there, then it will hold.

As you know, that will kill the clutch.

Excellent, thank you.

[aussie_eagle2512]

Im retaltively new to driving stick (first 1000 miles) and on most of my launches i launch .5-2 rpms but on this hill on my way 2 school sometimes i get so nervous that i hit the gas pedal wayyy 2 hard. like today i hit it and launched from the catch point at 3k rpm i no that is bad but how long will my clutch last if this happens sometimes .... also what are some signs ur clutch is failing .. i have a stock clutch at 33k miles .. also i never smelt clutch ... i think lol and i no some will say ebrake but ive think catch point is easier FOR ME at least

Perhaps when starting you just need to relax and just give it enough revs that you can definately hear it but thats about it. I try generally to get it no higher than 2000rpm when taking off. The key then is of course to be able to keep it above stalling level whilst getting going but after a while I'd imagine this would just become part of the routine. Also, personally I use the handbrake not just as a conveniance feature but actually it allows me to get straight on the accelerator when taking off therefore gives me a quicker start. I have now used handbrake starts not just on hills but about 98% of the time thanks to this. However, I imagine it does not need to be applied too much unless on a steep incline. Also, I have noticed my clutch start becoming spongy in its engagement as in when it hits the biting point it just has a slipping feel about it. It is not yet confirmed, but I suspect this may be the sign of a wearing out clutch. 33k miles is about 51,000km or so I shouldn't imagine a sensible driver shall have anything to worry about with the clutch at this point.

[DW10+BE4/5L]

First off, my post was made on my itouch, so yeah it was not my best. All i asked was 2 questions, 1. how bad is that for the clutch in terms of life, and secondly what are some signs of a failing clutch. I knew from previous posts that some will say HANDBRAKE launches. But I clearly said that I like the catch point launch because to ME it is easier than HANDBRAKE. I didn't know it was so hard to answer a question, but i guess on this forum if you don't use the HANDBRAKE or god forbid you ask another way you get flamed.

1. We would have to install a clutch wear-o-meter and analyze the data it would collect during operation to answer in any quantitative way. Without the wear-o-meter, we can only guesstimate.
2. The signs of a failing clutch are: you can't climb steep hills in high gears, the clutch slips even when you are not pressing the pedal.

[scionkid]

On a vehicle with a hydraulic clutch that doesn't share its fluid reservoir with the brake, there's a "wear-o-meter" As the clutch is worn down, the slaves cylinder should be pushing more fluid back to the reservoir. I don't know how good of an indication it is.