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Discussion Starter #1
i was sitting at a stop light tonight and got to thinking about the transmission on these cars and came up with a question.

since it is not an automatic and does not have a torque converter what keeps the car from stalling at a stop or wearing the clutch out. the clutch does not disengage cause you can creep so how does it work since it is a manual controlled by the computer.

the answer is probably simple but i can't come to a conclusion.
 

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The clutch does disengage. When you take your foot off the brake, the hill hold disengages and the clutch reengages. One way to defeat the hill hold assist is to pull up a little on the emergency/parking brake.
 

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The creep is inevitable as that's what vehicles with clutches do. Most human beings just aren't aware that their manual transmission cars creep because they likely aren't as talented with their stick shift abilities as they believe they are. In other words, in a manual transmission you can move the vehicle forward without once touching the accelerator pedal. Try it, and there's the identical creep that you are feeling in the smart.
 

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i respectively disagree i have owned 15 manual transmission cars (my handle is 4speed but thats another story) and never once did my car creep on a level perfectly smooth or otherwise street unless i got lazy with the clutch pedal. and if that was true than everyone with a manual transmission would have to keep their foot on the brake like automatics do when stopped.

i will try the hill hold thing and thanks for pointing out the logic. see i knew there had to be a simple answer
 

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and there's the identical creep that you are feeling in the smart.
The 450 does not do this. Fairly certain the only 451 that creep are the Can/US cars that they programmed to try to replicate an automatic transmission. I think it was a horrible idea, prefer the way the 450 works.
 

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i respectively disagree i have owned 15 manual transmission cars (my handle is 4speed but thats another story) and never once did my car creep on a level perfectly smooth or otherwise street unless i got lazy with the clutch pedal. and if that was true than everyone with a manual transmission would have to keep their foot on the brake like automatics do when stopped.

i will try the hill hold thing and thanks for pointing out the logic. see i knew there had to be a simple answer
Yes, your 15 manual transmission cars have that ability. You have more control than you choose to take advantage of. Key word here is "choose."
 

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The 450 does not do this. Fairly certain the only 451 that creep are the Can/US cars that they programmed to try to replicate an automatic transmission. I think it was a horrible idea, prefer the way the 450 works.
If you don't like the creep try moving the shifter to 'N' and back to 'D.' The 451 transmission is not preventing you from bypassing the creep feature. In my opinion the creep allows smoother and more responsive shifting, allows the auto driver to feather the throttle to get a feel for milking a higher gear from low rpms on up through the powerband instead of total guesswork while digging out of a hole at low speeds, etc,. The creep has its advantages for skillful drivers.
 

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The creep feature and clutch slip when shifting gears are two different chunks of software.

When I get tired of the spastic nature of creep in stop and go traffic, I toggle between N and D to move along in a smooth manner.
 

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The creep feature and clutch slip when shifting gears are two different chunks of software.

When I get tired of the spastic nature of creep in stop and go traffic, I toggle between N and D to move along in a smooth manner.
I like what Jetfuel did. He removed the Peizo element in the dash cluster . Now there's no "beep" when you pop up the brake lever 1 notch..:)
 

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If you don't like the creep try moving the shifter to 'N' and back to 'D.' The 451 transmission is not preventing you from bypassing the creep feature. In my opinion the creep allows smoother and more responsive shifting, allows the auto driver to feather the throttle to get a feel for milking a higher gear from low rpms on up through the powerband instead of total guesswork while digging out of a hole at low speeds, etc,. The creep has its advantages for skillful drivers.
I noticed the 'creep' a while back and do exactly what you suggested which is popping the transmission into N at a traffic light.
 

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Here's my explanation. :)

Normal manual transmission cars do not automatically creep like a smart. If you want to move slowly, you have to feather the clutch pedal and accelerator. Don't feather it enough, you stall.

In a smart, when you let off the brake or feather the brake, the clutch engages (note: the clutch is disengaged when the car is stopped) and tries to simulate feathering the clutch like you would in a real manual. It can save itself from stalling.

Actually, even the legit three pedal manual 453 even has anti-stall measures. I love that!

I do find the 451's creep mode a bit too aggressive for Chicago traffic. I'm always finding myself braking against an engaged clutch while in bumper to bumper traffic. Switching to Neutral solves this.

In the 453, the clutch is much less aggressive. Instead, the car just won't stop shifting gears. Of course, you can't blame the car for that, how is it supposed to know you're in bumper to bumper traffic? That said, switching to manual mode fixes that.

Part of me wishes I got a manual 453. Then I go outside, see that orange and white Edition #1 , then fall in love again. <3
 

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In some states, it is illegal to pop the trans in neutral at a light, or when rolling downhill. if the car is moving, it should be in gear. On the 451, you can pull up the E-brake and it will hold the clutch down and no more creep mode. I believe it has something to do with the hill assist. It is annoying when you are stuck in traffic (such as construction zones where you are going slow for miles) Manual Mode works best for those situations.
 

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I use the "creep" feature when pulling into my garage. Because I use the same small limited space as I used for my motorcycles, I pull in slowly. If I wish to keep my driver side mirror attached,I pull as far to my right as I can. I know it folds forward and a little back. Pulled out for pic.

We have long red lights here in Las Vegas, I most times put my other cars with automatic transmissions in neutral if I'm stopped at the red light. I see it no different as to being stopped at a red traffic light with a manual transmission and having it in neutral while the brake is on. Less chance of a foot slipping off the clutch while in first gear, even with the brake depressed (in a perfect world the car should stall) and rear ending the car in front or worse a person crossing in the crosswalk.
I never heard it was against any laws.
While briefly researching I found this,
snopes.com > Urban Legends > Automobiles
Reload this Page Illegal to put car in neutral at red lights
Now coasting downhill engine off in neutral maybe a different story. Not saying I haven't done it in a 67 VW no steering lock, manual steering and brakes, easy peasy. That's another thing entirely.
 

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When you are holding the brake as in being stopped the clutch is totally disengaged. As you start to let up on the brake pedal ever so slightly the brake switch signals the computer and the clutch begins to engage a little. If you start to let the brake pedal off and you are on a slight hill (the yaw sensor under the driver seat determines the incline uphill) the brake will hold slightly longer to hold the car in place until you apply enough throttle for the clutch to begin to engage without stalling the engine. Its an amazing feat of sensors and computer program. I think it does amazingly well. Remember the Fortwo was designed to be a city car, and that would include lots of stop and go traffic.

My only quipp with the whole clutch thing is when you are creeping ahead and the car starts bouncing the front end at around 10 mph, then you have to either touch the brake, speed up a little or throw it in neutral to stop it from bobbing. It's not perfect but interesting.

You can trip the system up though and this situation has about got me ran over a few times. You take off from a standing stop and at very light throttle. At around 10 mph the car is fixing to shift to 2nd. At that point you need quick acceleration, so you mash it to the floor. The car burps everytime. The computer was fixing to shift to 2nd and you mashed it which told it go to first and scream.
I run into this pulling into interstate from my house. There's two lanes of traffic each direction separated by a large median. I roll acrossed the first two lanes to the median divider which usually takes me up to about 10 mph and I prepare to turn left into the far side traffic. The car thinks I want to cruise slowly and prepares for that 1 to 2 shift and at the median I shove it down to accelerate to highway speed and it burps and there I sit cussing. You learn to anticipate and I can cure this situation by kicking the shifter into manual mode and holding it in first gear. DCO
 

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In some states, it is illegal to pop the trans in neutral at a light, or when rolling downhill. if the car is moving, it should be in gear. On the 451, you can pull up the E-brake and it will hold the clutch down and no more creep mode. I believe it has something to do with the hill assist. It is annoying when you are stuck in traffic (such as construction zones where you are going slow for miles) Manual Mode works best for those situations.
Weird law, also a law that's completely unenforceable in any realistic manner. Though, I've seen weirder laws. :D

I drive my 451 100% in Manual Mode. Chicago traffic is usually 0-10 mph at its worst. For me, that's basically just 1st gear. There is a whole lot of actual flat out stopping, starting, then stopping again 5 seconds later. Too much of it then Tucker's clutch actuator decides to throw a code then limp home mode.

I get around that by doing the same thing truckers do. Determine the actual speed of traffic then slide it into Neutral and coast. It's even better if there's a nearby truck because then I'll just coast with them. It's nice to keep up with traffic without really needing to actually stop & go like everyone else.

I'm also aware of the one notch thing with the parking brake. Seeing "BRAKE" in big red sets kinda of things off in my brain though, so I don't do it. Wish there was a way to make it so the light doesn't come on with the first click.

Thankfully by driving 100% manual I also avoid the front end bobbing thing DCO talks about. Then again I drive aggressively enough that I probably don't notice. :D
 

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Not all drivers react the same. worse case would be someone who doesn't have the mindset to correctly respond and there you go....
 

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Not all drivers react the same. worse case would be someone who doesn't have the mindset to correctly respond and there you go....
Agreed, and I can see how the law would exist. Perhaps you're driving a bus, heavy duty vehicle, or truck, those vehicles have no business coasting downhill in neutral. That is truly dangerous. But a runaway smart car or subcompact economy car shouldn't worry anybody. I don't live by coasting downhill, I'm usually a gear down just to prevent runaway speeds, but there has certainly been occasions that I have coasted downhill in neutral to save fuel.

This article also assumes everybody with the neutral idea is driving some large-engine vehicle that automatically shuts down cylinder banks which is ridiculous if you are in an older, or small-engine car.
 
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