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I live in Texas so I dont have much to add to this coversation (haha) but the steeper the hill, the more force the clutch and engine would have to exert to keep the vehicle from rolling back. Given the kind of hills in San Francisco, the force required may be too great for many cars to simply let out the clutch and have it hold without stalling.

My friend's old Honda would stall when gently letting off the clutch on level ground without gas. But I think that car had 90 hp ;-)
 

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Interesting discussion.

I was trained to use a handbrake on a hill, some 28 years ago. Let me say that we have lots of hills here in BC, and I last drove in San Francisco 4 weeks ago. Yes, there are some big hills there.

My 17 year old daughter learned to drive last year. I taught her, and we also sent her to a driving school. She learned on a manual (I insisted, now she likes it). I taught her to start up on a steep hill using the handbrake. The driving school said no way, not acceptable. The test will involve starting on a hill, not rolling back at all, and the use of the handbrake is frowned upon.

The technique they taught her was right foot on brake, left foot on clutch. Just before you want to start up (ie not 2 minutes early), let the clutch out just until the revs start to drop (ie 50-100 rpm drop). Hold the clutch right there. Move right foot to gas pedal, throttle down and clutch up in unison. I was a doubter, but it worked fine, and she is very smooth with it. The clutch doesn't get smoked for the few seconds involved (at low revs). And, she doesn't roll back at all. The 115 hp Toyota doesn't stall.

So, I still use a handbrake when someone is inches behind me. She may do so as well, occasionally. But with the technique above, it isn't really necessary.
 

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jcl10 said:
The technique they taught her was right foot on brake, left foot on clutch. Just before you want to start up (ie not 2 minutes early), let the clutch out just until the revs start to drop (ie 50-100 rpm drop). Hold the clutch right there. Move right foot to gas pedal, throttle down and clutch up in unison. I was a doubter, but it worked fine, and she is very smooth with it. The clutch doesn't get smoked for the few seconds involved (at low revs). And, she doesn't roll back at all. The 115 hp Toyota doesn't stall
This is the technique I have always used. I have never used the hand brake, even on pretty steep grades (you just stomp on the gas quicker). You can also 'three foot' it for hills that are really steep.

I can imagine that certain situations might call for it though. A car with very little torque on a steep hill would probably need the hand brake (another reason to avoid gutless cars). :thumbup:

--SONET
 

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jcl10 said:
Interesting discussion.

I was trained to use a handbrake on a hill, some 28 years ago. Let me say that we have lots of hills here in BC, and I last drove in San Francisco 4 weeks ago. Yes, there are some big hills there.

My 17 year old daughter learned to drive last year. I taught her, and we also sent her to a driving school. She learned on a manual (I insisted, now she likes it). I taught her to start up on a steep hill using the handbrake. The driving school said no way, not acceptable. The test will involve starting on a hill, not rolling back at all, and the use of the handbrake is frowned upon.

The technique they taught her was right foot on brake, left foot on clutch. Just before you want to start up (ie not 2 minutes early), let the clutch out just until the revs start to drop (ie 50-100 rpm drop). Hold the clutch right there. Move right foot to gas pedal, throttle down and clutch up in unison. I was a doubter, but it worked fine, and she is very smooth with it. The clutch doesn't get smoked for the few seconds involved (at low revs). And, she doesn't roll back at all. The 115 hp Toyota doesn't stall.

So, I still use a handbrake when someone is inches behind me. She may do so as well, occasionally. But with the technique above, it isn't really necessary.
I do this also, but understand that this method takes more coordination then the handbrake method. Not everyone is as good at driving a manual as we are ;)
 

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The handbrake is like training wheels to me; a false sense of security and yet another thing to worry about on launch.

I've tried the handbrake method once or twice and found it useless. Here in Providence we have some SF style hills and I've learned to launch with very little backward motion. I agree, the steeper the hill, the faster the transition from brakes to accelerator.

I'm excited about this feature though, sounds nice for parallel parking on steep hills.
 

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jcl10 said:
IThe clutch doesn't get smoked for the few seconds involved (at low revs). And, she doesn't roll back at all. The 115 hp Toyota doesn't stall.
I suppose it's not too convenient for your daughter to come to Fillmore st and try it in her toyota? It's "only" a 20% hill, and my 118hp honda doesn't have enough torque to hold itself up at 200 rpm and clutch half depressed. NOT even close. Who knows, your daughter in her toyota may be able to, and she'll probably enjoy the trip too!

If you dont want to roll back the way you described, your car should have enough torque to climb up the hill at idle with clutch out. That's basically 10% hill or less for most cars. If you have to roll back, then you risk either hitting the car behind, or jolt forward and hit the one in front.
 

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I think the bottom line is that the technique of holding the car with a partial clutch raise sure works, but not everywhere as it may be unable to hold the car if the hill is too steep. Want proof? On a very steep hill an automatic transmission car in Drive would roll back the hill if you let go of the breaks. End of discussion! ;)
 

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Could you tell me what "double-clutching" is? I've heard the term mentioned in connection with trucks though I dont know what it means in that context either!

dsbmw said:
This might seem like a dumb question, but I currently don't have the opportunity to experiment with this feature on a test drive. I'm wondering if there's a quick way (i.e. much faster than the 2-3 seconds it'll take to do it on its own) to defeat the hill-assist now present on the manual E90s. I'm not sure how it'll work out, but in places such as the steep inclines of San Francisco, I can imagine times when I would much rather prefer the guy in front of me to have this feature instead of me. Often times, it's easy to notice a rookie or tourist in the city by how much they roll back starting off on steep hills. When I notice someone in front of me struggling too much upon advancing, I quickly step into the clutch to roll back with him, coming to balance my car within six inches of the guy behind me, granting all possible space to the front car. I reckon the occasional slight wear of my clutch is minor compared to the scratches on my front bumper. Two-three decades ago, when there where a lot more manual drivers, one could frequently witness this phenomena: an out of town driver not knowing how to manage his manual car on hills, and 2-3 experienced city drivers behind him, who'd immediately roll back in unison giving the rookie a full car's distance to get his act together (upon failure, there would be a colorful exchange of words…). Anyhow, would double clutching, or a momentary shift to 2nd before reengaging 1st allow one to begin rolling faster? Now that I think about, parallel parking on hills will also be cumbersome if one needs to wait 2.5 seconds to begin rolling in the opposite direction of the gear once the clutch goes in, short of actually shifting. Among my long list of why I prefer a manual to an auto, quicker parking into tight spots on inclines is one of them; I hope I don't have to give it up.
 

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Deburn
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I think getting a drivers license in the US or Canada is a joke compared with what I've heard of other (European) countries. I learnt how to drive in Dubai UAE and credit my driving ability to the training I was forced to undergo before I could even apply to take a driving test!

silverado said:
Yes, if you are not starting up. The hill assist feature is designed to detect when you are about to try to move the car up a hill from a stand still and it engages the breaks for you. At all other times, you are on your own.

For background knowledge, starting a manual transmission car up a hill usually requires using the hand breaks to keep the car in place while the first gear is being engaged enough to support the car. In fact, it is part of a standard driving test (if you do it in most countries other than the US which require taking the test with a manual transmission car). It's a basic technique that any manual transmission driver needs to know.
 

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deburn said:
Could you tell me what "double-clutching" is? I've heard the term mentioned in connection with trucks though I dont know what it means in that context either!
Get ready for some long winded explaination..... :yawn:

Do you know what rev-matching is?
 

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I'll throw in my 2 cents. Having visited SF on many occasions, I don't think using the hand "BRAKE" (correct spelling) is necessary, but the hill assist feature basically eliminates the need for it.

The original poster made some very good points about being able to roll back along with the person ahead of them is they were rolling back into him. I have a suggestion: Leave a little more room in front of you, so they have room to roll back... That's what I do. You shouldn't be within 2 feet of the person anyway (even in SF), and if they roll back more than 2 feet, there's not much you would be able to do (since there is probably someone behind you closer than that anyway). You can only roll back so far with someone behind you.

The original poster also lamented not being able to roll backwards immediately while parallel parking... This is probably the worst problem you will encounter with the system. 2 seconds is not that long but it can seem like an eternity when you are trying to park. If you lift the clutch slightly, the hill assist is defeated, but also if you are in reverse, it will allow you to roll backward, so either method will allow you to roll back right away. Even with hill assist active, however, I somewhat doubt the safety of rolling back within 2 seconds, as you probably have not had time to look behind you before rolling back right after coming to a stop. The 2 seconds the system is active will give the driver enough time to turn around and verify that there is no one in their way before rolling back.

By the way, a better way to avoid rolling back (in a car without hill-assist) is to use the "heel-toe" method on the brake/accelerator. You should be able to hold the brake and depress the gas slightly with your right foot, and manage the clutch with the left in such a way as to not need to have to let the clutch out before moving your right foot to the accelerator. The BMWs pedals are set up great for heel-toe, (yet another of the things that make our cars great driver's cars) but unfortunately, many other cars are not. I drove a lot in SF in my old 83 GTI and used the heel-toe method and never rolled back at all (unless I meant to of course). I would never buy any Manual Transmission car that was not set up well for heel-toe. NEVER!
 

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I grew up driving in San Francisco and have driven many different cars in this city (almost all with manual transmissions) for my entire life. I know how to heel and toe, etc. It's true, that most of the time you don't need the handbrake. That's true 99+% of the time. However, you can find yourself in circumstances on some of the steepest hills in this city where you would be crazy not to use your handbrake. I don't know how well the hill assist capability of the E90 will work in extreme circumstances. I know I will have my hand ready on the handbrake when the time comes to find out. No shame in that. The handbrake is our friend.
 

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I am very doubtful on being able to start a car uphill without rolling backward if you don't use the handbrake. The technic which is described earlier won't work if the car has a small engine, because the torque won't be enough to maintain the car on some hills. So you will move backward a bit at least... It will just slow down the speed at which you roll backward, but not prevent you from doing so...

I lived 2 years in SF, and in some streets I even had to use handbrake with an automatic car ! Otherwise the car would go backward a bit before I start. The torque is simply not enough if the hill is too steep...

;)
 

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Athos said:
I grew up driving in San Francisco and have driven many different cars in this city (almost all with manual transmissions) for my entire life. I know how to heel and toe, etc. It's true, that most of the time you don't need the handbrake. That's true 99+% of the time. However, you can find yourself in circumstances on some of the steepest hills in this city where you would be crazy not to use your handbrake. I don't know how well the hill assist capability of the E90 will work in extreme circumstances. I know I will have my hand ready on the handbrake when the time comes to find out. No shame in that. The handbrake is our friend.
I agree, there is no shame in using the handbrake. You do what you have to when you have to.

In my experience, the hill assist feature is definitely strong enough to hold you on the steepest of hills. I believe it is calibrated to hold the car no matter how steep the hill. I think this is a great feature for those that do live in SF, Pittsburgh, and Seattle, where there are steep hills that normally would require the handbrake at times. I disagree with the original poster who says that it is a bad feature because people will roll back into you and you can't roll back quick enough to avoid them. Leave more room!

If everyone had this feature, no one would roll back into anyone!
 

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Discussion Starter · #37 ·
I noticed this thread went all over the map and after the first couple of replies, it never addressed the original question; it just demonstrated lack of definitions by some and poor reading by others.
I simply wanted to know from those who already have the manual version of the car, what's the quickest way to force the car to roll on an incline once the hill-assist feature engages. It’s not a single judgment on whether the feature is good or not. It’s just that I can think of scenarios when I don’t want to be held up. Consider having to shoe-horn yourself into a very tight spot on an incline where you’ll have to do multiple back and forth maneuvers. In an slushbox, you’ll have to constantly shift between D and R; in a manual, you can use both hands to spin the wheel quicker, step into the clutch, roll, brake, spin the wheel in the other direction, release (engage) clutch and drive opposite to the roll, brake, step into the clutch, roll, brake…etc. If it’s done only once it’s no big deal, if it’s multiple times, the manual is much quicker than the auto, as both hands can be used to spin the wheel stop-to-stop without having to go to the shifter. In a flat area, it’s a mute point, but I can actually park faster into awkward tight spots when there’s a 5% incline as I don’t need to shift at all. Albeit, such scenarios occur seldom, but more to some than to others. Once the hill-assist engages, if simply releasing the clutch pedal to the catch point and then pressing it back down, instantly removes the brake pads from the disks, then it’ll be an easy thing to get used to.
BTW, I do leave the proper space between the car in front of me and myself, and quite instinctively adjust it depending on parameters such as hill grade, make and model of the vehicle in front, etc. But leaving too much space between cars is also bad driving, it adds to congestion and backs up lights several blocks down. Yet, being able to apply a defensive manuvouer to quickly roll back is not a bad thing, considering it can be used to readjust the initial space before another car drives up behind. Imagine leaving a proper distance on Nob (snob) hill to the car in front, yet it’s one of those prideful people who insist they can manage any hill without using the brake and don’t have a hill-assist feature. In such case I’d like to defeat my hill-assist quickly and roll back as much as possible once they stall and come at me.
Incidentally, those who claim that simultaneous braking while accelerating from a steep hill isn't necessary to prevent rolling back if one just knows how to release the clutch sufficiently before letting off the brake and stomping the gas might do well in defining "steep hill." To get an idea of what someone in SF (or Wellington, or other cities with *real* hills) thinks of “steep,” consider going to the steepest street in your town. While parked, open a water bottle and fill a cup with straight walls up to half its diameter from the rim (e.g. if a mug has a 3” diameter, do not fill the top 1.5”). Now, very carefully open one of those awesome cup holders your car has, and place the cup in it as gently as possible. If you haven’t already spilled water by now, you’re not on a steep hill. You’re still below 26 degrees; we have a few 30’s around here. If you’re above that angle, and can master the simultaneous brake technique, you could take a sip from the cup and drive forward without spilling any more. The sine of 30 deg = 0.5. If you still don’t get the picture of what that implies in your flat neighborhood, drive to the top floor of a multi-story parking lot and look for a small car that weighs half as much as yours. Fasten a steel cable around its bumper and yours, back up against it and push it off the building. Hold your car solely with your brakes at the edge of the roof, such that if your roll back a few inches you also go off. Now, try your no-brake technique and move forward. Other than the inertial moment of your own car on the flat surface, it’ll be roughly equivalent to a 30deg hill. If you don’t go over, you’re likely to be a nuisance stopped anywhere as your idle is set absurdly high.
Personally, I prefer the toe-and-heal technique to the hand-brake; I think it’s a smoother transition when all four brakes are engaged and the weight is taken off the springs on the back. Yet, for good reason, the hand-brake technique is what is expected in SF. On a rainy night with wet leather soles, toe-n-heal can easily go haywire and the right hand should be on the hand-brake instead of the cell phone (unless you have a Detroit special with the E-brake release deep under the dash, -who thought that one out?!). Yet, I’ve met women with small feet who are remarkable at toe-healing with 4” stiletto heals. Unlike most people who actually “heal” with the side of the foot, they control the gas pedal with the tip of their heal such as not to scuff the side of their $300 designer shoes. Of course, this is for starting from a hill; I’ve never been in a car (nor want to) where someone on stilettos was toe-healing for rev matching to negotiate a curve on the limit.
Wondering if this horse hasn't been beaten to death by now.
 

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Discussion Starter · #38 ·
For the person who asked what rev matching and double clutching is, I’d suggest you google it outside this forum. I’ll offer a 2 cent, 2 min reply, but I’ll likely get flamed for writing anything and you’ll get lots of conflicting posts. In it’s shortest explanation, to double-clutch, you shift from gear to neutral, momentarily release your foot from the clutch pedal, and step back into the clutch as you shift to the next gear. For rev matching, tap the gas pedal before releasing the clutch so that the engine’s speed is close to what its load will be when you release the clutch. That is, the rpm’s of the engine should be similar to the rate of turn of the selected gear that is being turned solely by the car’s wheels while the engine is disconnected from the transmission. You pretty much do this when regularly working through the gears at moderate rates, yet those who’re into performance driving will have to work more diligently at it when driving hard, particularly for instance, when cornering and not wishing to upset the balance of the car while down shifting by introducing an abrupt engine break. Yet, knowing that they’ll need the lower gear after the turn, they’re already on it when they exit the corner. Hence, the need for toe-healing the brake and gas, as they’re simultaneously slowing down coming into the curve and need to rev match the engine. Double clutching is hardly ever done today, as the simplest manual tranny in a car (for big rigs, it’s another story) has synchronizers that help engage each gear. Yet, together with rev matching, it was a way to help smooth the transitions between gears in older cars (pre 70’s). However, if you have a very high mileage car and find it difficult to engage a gear, it’s respective syncro is likely worn, and double clutching/rev matching will help enter the gear. I’ve never been into high end performance driving, but many of these techniques in their simple form I had to learn as a teenager having nothing other than my beat up bug in SF. The bungee cord type hand-brake cable was worthless in holding the car on a hill so toe-healing was a necessity. Moreover, the old ‘match-box’ tuned points and over stripped 10mm bolt that held the distributor in place only lasted a few hundred miles before losing half the power of the 45HP engine. Hence, if I was on 3rd gear and had to make a right turn and go up a modest hill, I’d either have to stop and go into 1st gear and stay there, or without slowing down too much, forcefully shift from 3rd to 2nd on the turn by double clutching and toe-healing to rev match and climb up at twice the speed on 2nd, at about 20mph. Those were the days…
 

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Heh, so much for "end of discussion".

CC 330i said:
By the way, a better way to avoid rolling back (in a car without hill-assist) is to use the "heel-toe" method on the brake/accelerator.
I was wondering when someone will bring this up as the "magic" technique. People do crazier things with their cars, so it could qualify as a ftd thing to do with your bimmer if the handbrake is too boring for you. I suppose that is only thing h&t will be good for when it becomes obsolete on autocross tracks. On a car without the hill assistance, that is.
 
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