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View Full Version : 1st gear accel/decel jerky


swchang
07-27-2004, 01:04 AM
Has anyone else noticed jerkiness in 1st gear? In particular, I can think of two scenarios. One is if you're on the throttle in first and then you suddenly let off. The car doesn't smoothly slow to a crawl. The second is if you're on the throttle, let go, then step on the gas again (e.g. rolling stop through a stop sign or before turning onto a street from a service road).

Any ideas if this is normal, and if it is, why it happens? DBW? :dunno:

FenPhen
07-27-2004, 01:17 AM
I dunno about DBW, but aren't all manual cars like this in first gear? I'd guess it's due to the high gear ratio, which effectively magnifies the gas pedal input you give.

dingfwen
07-27-2004, 01:39 AM
Yup. Totally normal. In first gear, your engine has the most mechanical advantage over your wheels and in sixth gear, it has the least. You can think of gears like a lot of interlocking levers with different lengths. What this means is that in first gear, your engine spinning up or down will greatly influence your wheels due to the mechanical advantage, thus the jerkiness when you lift/put down the gas. In sixth, the engine has much less influence over the wheels, so it is "dragged" along by your wheels and the mass of your car, resulting in smoother acceleration and deceleration.

In case none of that made any sense, check out how gear and transmissions work at:
http://www.howstuffworks.com. It's a great site!

shizat63
07-27-2004, 05:20 AM
Yep, mine is exactly like that. Kinda like it spools up and the car gets really jerky. You gotta just learn to compensate when in 1st gear

Moderato
07-27-2004, 06:49 AM
Yep, mine is exactly like that. Kinda like it spools up and the car gets really jerky. You gotta just learn to compensate when in 1st gear


Exactly. In fact the instant on/off nature of the throttle with a manual tranny is one of the things I love about it.

andy_thomas
07-27-2004, 07:18 AM
Has anyone else noticed jerkiness in 1st gear? In particular, I can think of two scenarios. One is if you're on the throttle in first and then you suddenly let off. The car doesn't smoothly slow to a crawl. The second is if you're on the throttle, let go, then step on the gas again (e.g. rolling stop through a stop sign or before turning onto a street from a service road).

Any ideas if this is normal, and if it is, why it happens? DBW? :dunno:
It's because it's a manual, not an e-z-e-ride slushmagic (which, unless you lock it in first gear, freewheels when you take your foot of the gas). Also manuals tend to be lower-geared than autos, especially in first.

Bigerr19
07-27-2004, 11:19 AM
My old E36 328is used to do the same thing, even more noticable when the air-conditioning was on.

richard
07-27-2004, 06:38 PM
I think the Bimmer is pretty good compared to other cars. I can creep along in stop and go traffic in 1st without having to use the clutch unless I'm coming to a complete stop. It's not near as jerky as my girlfriend's Honda del Sol. Her car needs judicious clutch use even in 2nd gear when accelerating and decelerationg.

swchang
07-27-2004, 07:05 PM
Okay, I figured the jerky decel was due to the manual transmission. What really gets my goat is the jerkiness upon accelerating after decelerating. I'm surprised I don't get whiplash after each episode. Anyway, how do I avoid it? Just ease more gently onto the throttle? Any other ways?

FenPhen
07-27-2004, 07:12 PM
Anyway, how do I avoid it? Just ease more gently onto the throttle? Any other ways?
Yes. Ease on the throttle and it won't jerk. Or, go to second. (You don't need to tool around a parking lot in first gear all the time if you can safely bring your speed up to maybe 15-20 mph.)

operknockity
07-27-2004, 08:12 PM
I had those problems when I first got the bimmer. It was the difference between a very loose and sloppy 16 year old Toyota vs the brand new and very stiff bimmer clutch.

I did notice that after they installed the software fix for the idle stall problem that whatever remapping of the idle rpm's and throttle response has made 1st a touch more finicky than it was even when brand new.

Ashe too
07-27-2004, 08:34 PM
A Buick with an automatic would solve the problem nicely :rolleyes:

doeboy
07-27-2004, 08:43 PM
Okay, I figured the jerky decel was due to the manual transmission. What really gets my goat is the jerkiness upon accelerating after decelerating. I'm surprised I don't get whiplash after each episode. Anyway, how do I avoid it? Just ease more gently onto the throttle? Any other ways?

You could try getting out of the car and pushing it for a smoother acceleration...

swchang
07-27-2004, 09:30 PM
You could try getting out of the car and pushing it for a smoother acceleration...

How about I pay you to ride with me and get out and push when I want smooth acceleration? My offer is this: I'll jab my finger into your stomach to hear you giggle "hehe!" with delight for each usage of your services.

doeboy
07-27-2004, 09:34 PM
How about I pay you to ride with me and get out and push when I want smooth acceleration? My offer is this: I'll jab my finger into your stomach to hear you giggle "hehe!" with delight for each usage of your services.

How 'bout.... "NO"

swchang
07-27-2004, 09:42 PM
How 'bout.... "NO"
:(

doeboy
07-27-2004, 10:12 PM
:(

:p :neener: :D

Fast Bob
07-27-2004, 10:52 PM
In first gear, you have a torque-multiplication factor of about 12 1/2 times....this is analogous to having a thousand-watt lightbulb hooked up to a quarter-turn dimmer switch.
Once you learn to modulate that right foot, you`ll be OK.

Regards,
Bob

AndDown
07-27-2004, 11:11 PM
Just like everything in life, there are pro's and con's. It's all about what you have to put up with (or adapt to) to enjoy what you want.

Orient330iNYC
07-27-2004, 11:17 PM
yup, 1st can be touchy like that.
the lower the gear the greater the effect of engine braking.

DBW doesnt help it any...

Bavarian
07-28-2004, 12:38 AM
LOL well I'm sure many of you will say that the Steptronic does not count as an example, however my Step 330i is VERY jerky in 1st gear (exactly the same symptoms as you described). And it's been that way since day 1. You just gotta learn to tame the beast once you learn when it likes to be jerky. :)

teknic330
07-28-2004, 02:11 AM
I use the clutch alot to get my car moving smoothly. I just depress the clutch while slowing down and slip it while taking off slowly. This is probably wearing the crap outta my clutch, but at least my head won't be bobbling around.

armaq
07-28-2004, 02:40 AM
My M3's 1st is butter smooth

Drove a 5spd IS300 for a while. In that car even 3rd is jerky "nod your head!"

Jspeed
07-28-2004, 05:17 PM
Is this your first manual tranny?

I just naturally learned to hit the clutch when I have to suddenly let off the gas in 1st gear. I think most experienced drivers do that b/c they know the car WILL be jerky otherwise.

operknockity
07-28-2004, 05:51 PM
Drove a 5spd IS300 for a while. In that car even 3rd is jerky "nod your head!" When I test drove one of those, I found the clutch to be very very stiff and the gas pedal to be very very soft (almost to the point where a feather would floor it), so I was constantly missing shifts in every gear and bucking down the road something fierce. :( Don't know whether that was just the one car they had available for test drives or it was just the way they made 'em. Never drove another one because I decided that the car was just too small, and the Sport Cross version, which I was more interested in than the sedan, was not available with a stick.

armaq
07-28-2004, 06:11 PM
When I test drove one of those, I found the clutch to be very very stiff and the gas pedal to be very very soft (almost to the point where a feather would floor it), so I was constantly missing shifts in every gear and bucking down the road something fierce. :( Don't know whether that was just the one car they had available for test drives or it was just the way they made 'em. Never drive another one because I decided thatthe car was just too small, and the Sport Cross version, which I was more interested in than the sedan, was not available with a stick.

I guess they are all like that. I was on an IS300 forum and there were members there who had been driving those cars for months or even years and still couldn't shift smoothly

swchang
07-28-2004, 09:36 PM
Is this your first manual tranny?

I just naturally learned to hit the clutch when I have to suddenly let off the gas in 1st gear. I think most experienced drivers do that b/c they know the car WILL be jerky otherwise.

Yup. :) I've been just easing off the gas when in first instead of suddenly letting go. If I have to do it suddenly, then I use the clutch.

FenPhen
07-28-2004, 11:26 PM
Yup. :) I've been just easing off the gas when in first instead of suddenly letting go. If I have to do it suddenly, then I use the clutch.
You need a fine foot to let off in first (it's not that hard when you're used to it). For a sudden but not-jerky stop, start rolling off the gas just a split-second before you push in the clutch.

armaq
07-29-2004, 01:11 AM
Yup. :) I've been just easing off the gas when in first instead of suddenly letting go. If I have to do it suddenly, then I use the clutch.

We can swap cars. You get the butter smooth 5 speed with more power and better handling. Interested? :p

swchang
07-29-2004, 08:13 AM
We can swap cars. You get the butter smooth 5 speed with more power and better handling. Interested? :p

Hmm, yeah, um, nah, it's okay. ;)