BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
M2 Technical Topics > Track / Autocross / Dragstrip > Struggling to get into 2nd gear at autocross - Need help

Post Reply
 
Thread Tools Search this Thread
      11-29-2018, 03:35 PM   #1
Diem68
New Member
3
Rep
9
Posts

Drives: 2017 M2
Join Date: Oct 2018
Location: Orlando

iTrader: (0)

Struggling to get into 2nd gear at autocross - Need help

My M2 is doing something funky, and I have no idea what to do about it.

On the 1st to 2nd shift, the gate into 2nd gear is sometimes blocked off preventing the shift to 2nd. It happens more frequently while shifting in a turn, but still sometimes happens in a straight. Short shifting seems to help most of the time, but that costs time on the clock. It's happened to every person who's driven my car.

I took the car to the dealership, but since it's practically impossible to replicate the problem on the street, they said the car is fine. But it's not.

Any guidance would be greatly appreciated.

David
Appreciate 0
      11-29-2018, 03:43 PM   #2
detroitm2
Colonel
detroitm2's Avatar
United_States
2427
Rep
2,526
Posts

Drives: 2018 M2
Join Date: Aug 2018
Location: Michigan

iTrader: (2)

Garage List
2018 BMW M2  [0.00]
Weird.. Only car I've experience that on is my challenger, which actually has a 2nd gear lockout "feature" to improve fuel mileage.. Pretty sure the M2 doesn't have that.
Appreciate 0
      11-29-2018, 09:00 PM   #3
kpaso
Second Lieutenant
183
Rep
289
Posts

Drives: BMW
Join Date: Jun 2018
Location: Bay Area

iTrader: (0)

I have the same problem going from 3rd to 2nd. It happens often as approaching a turn at speed. I believe I've also had the same problem going from 1st to 2nd.

I know I'm not the only one either since I've commented on a post about this before on here.
Appreciate 0
      11-29-2018, 09:32 PM   #4
acl26
Private
37
Rep
73
Posts

Drives: 2018 BMW M2
Join Date: Jul 2018
Location: North America

iTrader: (0)

If it's happening going into or out a turn it's most likely deflection on your mounts and bushings. I have trouble getting into gears at exits with harder acceleration at The Ridge race track. Fixed this with harder tranny mount and diff bushing inserts.
Appreciate 0
      01-01-2019, 10:21 PM   #5
M2OG
Lieutenant
399
Rep
463
Posts

Drives: a car
Join Date: Jun 2014
Location: California

iTrader: (1)

Are you running a clutch stop?
Appreciate 0
      01-02-2019, 01:01 PM   #6
bbnks2
Colonel
1207
Rep
2,025
Posts

Drives: 135i N55
Join Date: Jan 2017
Location: NY

iTrader: (0)

100% this is mainly due to transmission bushings and shifter carrier bushings. Move to a street poly or race poly...

You also shouldn't upgrade transmission bushings without upgrading motor mounts. Id look to put street poly in your engine mounts, transmission mounts, and shifter carrier. Then it's a downward slope to wanting stiffer differential bushings...

The gs6-45bz and gs6-53bz ZF transmission never had a good 2nd gear either... it has been notchy on ever bmw since mid 2000's when they started using them... Makes a good drag time difficult when you can't power shift into 2nd.

Last edited by bbnks2; 01-03-2019 at 07:28 AM..
Appreciate 1
ddk632583.00
      01-04-2019, 10:23 AM   #7
Proctor750
Lieutenant
426
Rep
538
Posts

Drives: E30 M3
Join Date: Aug 2018
Location: Hattie B's

iTrader: (0)

Rubber + weight of car + momentum = your problem.
Appreciate 0
      01-13-2019, 03:32 PM   #8
Diem68
New Member
3
Rep
9
Posts

Drives: 2017 M2
Join Date: Oct 2018
Location: Orlando

iTrader: (0)

Quote:
Originally Posted by Natek View Post
Are you running a clutch stop?
I was originally running a clutch stop, but took it out, and the problem still persisted.
Appreciate 0
      01-13-2019, 03:34 PM   #9
Diem68
New Member
3
Rep
9
Posts

Drives: 2017 M2
Join Date: Oct 2018
Location: Orlando

iTrader: (0)

Quote:
Originally Posted by bbnks2 View Post
100% this is mainly due to transmission bushings and shifter carrier bushings. Move to a street poly or race poly...

You also shouldn't upgrade transmission bushings without upgrading motor mounts. Id look to put street poly in your engine mounts, transmission mounts, and shifter carrier. Then it's a downward slope to wanting stiffer differential bushings...

The gs6-45bz and gs6-53bz ZF transmission never had a good 2nd gear either... it has been notchy on ever bmw since mid 2000's when they started using them... Makes a good drag time difficult when you can't power shift into 2nd.
I'm thinking this is the problem, but unfortunately I run in 'stock' class and can't upgrade the bushings.
Appreciate 0
      01-14-2019, 03:46 PM   #10
Old Geezer
Private First Class
204
Rep
189
Posts

Drives: 2019 M2C
Join Date: Oct 2016
Location: Houston, TX

iTrader: (0)

I’ve never encountered this problem. What I have noticed is that I occasionally need to execute a 2->3 shift while autocrossing, and the linkage doesn’t like to be rushed. While the gearchange is sublimely smooth and precise in street driving, one can’t be in too much of a hurry.
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 03:16 AM.




m2
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST