[Skyhigh]

It's Saturday, so I had some fun test-driving the new 2-Series Gran Coupe (unfortunately with the silly 218i engine), but also the new (F40) M135i xDrive.
What a difference.



Although 2 cylinders, 1L and 54 PS less than the 440i M Performance, the M135i engine offers subjectively very similar engine and acceleration feeling.... I would say even more "spectacular" in a way, as the light steering and quick acceleration made it seem it is not hard to lose control in a turn.

HOWEVER, what shocked me the most was the transmission. In Sport mode (on the stick), shifting gears in full acceleration gives a serious kick in the back! It literally kicks you like a horse! In normal mode, it is soft and comfortable. Huge difference.

On my 440i, there is only a very marginal difference in how harsh the transmission changes gears between normal and sport setting on the stick!? It does maintain higher RPMs and it does seem to change gears slightly quicker, but in comparison to the M135i, the shifting is butter-soft!?

Is there something wrong with my transmission or what is your experience guys? It is supposed to be the same (or a variant of the same) gearbox...

[eddymerckx3]

Originally Posted by Skyhigh

On my 440i, there is only a very marginal difference in how harsh the transmission changes gears between normal and sport setting on the stick!? It does maintain higher RPMs and it does seem to change gears slightly quicker, but in comparison to the M135i, the shifting is butter-soft!?

Is there something wrong with my transmission or what is your experience guys? It is supposed to be the same (or a variant of the same) gearbox...

Just to b clear, ur current 440i trans shifting is “butter soft” and “quicker” then ur test drive comparison models, and u r asking whether there is something wrong with ur trans?

[Skyhigh]

You misunderstood or maybe I did not explain it well. Let's simplify:

440i:
- Stick in normal - shifting of gears very soft
- Stick in Sport - shifting arguably harder, subjectively quicker than in Normal.

M135i:
- Stick in normal - shifting of gears soft
- Stick in Sport - significantly harder shifting with pronounced "kicks" in the back. Day and nicht difference from Normal, much harsher.

Whether the 440i is shifting faster than the M135i despite being softer is impossible to say. I suspect not.

Main exam question:
- Is the difference in gear-shifting between Normal and Sport (e.g. acceleration full throttle from 0) pronounced in your 440i-s and do you get any sort of kicking in the back in Sport?

Any theories why the difference? (Should be the same gearbox..., the M135i has lower torque)

[Elvisfan]

I’m no expert on this stuff. But, you are talking about 2 entirely different cars. They are tuned differently. They have different motors. Plus 1 claims to be an M variant. Why would you possibly think that the cars should drive the same? It sounds like you are looking for a problem when there isn’t one.

[Skyhigh]

Not at all expecting them to be the same.

However wouldn't you expect a 4cyl, 2L, -54PS, -50Nm engine to be at least somewhat inferior to a 6cyl, 3L, +54PS, +50Nm engine (despite а weight difference)?

And mainly - I did not expect such a fundamental difference in the transmission, in Sport mode. That's why the question. Not looking for a problem, just puzzled. I have some very vague memory that I have felt some kicking in Sport long time ago.... but not sure if it was on my car at the very beginning or on something else.

[smrtypants44]

I would suspect that the FWD, transverse nature and compact transmission packaging of the 135i has some to do with the smoothness of the shifting in sport- less balanced setup than longitudinal i6 setup in the 440.

[328iX]

I agree.

I got an X2 M35i as a loaner and wow, it shifts hard and fast as hell. It's really easy to chirp the tires in second and I believe even third gear.

I've driven plenty of new Audis with DCT and it feels just as quicker if not quicker.

[HighlandPete]

M135i uses the Aisin gearbox, not the ZF. Add the drivetrain layout, different software, that's probably your answer.

[Skyhigh]

Originally Posted by HighlandPete

M135i uses the Aisin gearbox, not the ZF. Add the drivetrain layout, different software, that's probably your answer.

You are correct. I was mislead by the previous 1-Series. The F40 uses Aisin gearbox according to Wikipedia, not ZF.

OK, if someone with 440i could confirm there is no "kick" in Sport setting of the transmission, we would at least know it's all as it should be.

I must say though, the kick gives the M135i quite an aggressive feeling and vibe. Liked it

[eddymerckx3]

Originally Posted by Skyhigh

You are correct. I was mislead by the previous 1-Series. The F40 uses Aisin gearbox according to Wikipedia, not ZF.

OK, if someone with 440i could confirm there is no "kick" in Sport setting of the transmission, we would at least know it's all as it should be.

I must say though, the kick gives the M135i quite an aggressive feeling and vibe. Liked it

so...again, just to clarify, u seem to be equating a "kick" in the trans as GOOD and "butter soft" as BAD/INFERIOR??? The ZF trans in the F30 series will always yield superior shifting and managing of engine power to drive shafts, compared to the inferior trans in the 1 series. Just bcuz you don't feel a kick in your 3 series (even in sport) it doesn't mean u r somehow not utilizing all the power ur engine, nor is it less fun.

[Skyhigh]

Originally Posted by eddymerckx3

so...again, just to clarify, u seem to be equating a "kick" in the trans as GOOD and "butter soft" as BAD/INFERIOR??? The ZF trans in the F30 series will always yield superior shifting and managing of engine power to drive shafts, compared to the inferior trans in the 1 series. Just bcuz you don't feel a kick in your 3 series (even in sport) it doesn't mean u r somehow not utilizing all the power ur engine, nor is it less fun.

At least now I know you are simply not reading and it is not me explaining it badly.

I never said what you are speculating.... neither do I drive a 3-Series.

Thank you for your input. Let's hear other voices.

[drdino]

The kicks can be, and actually are, engineered in. M-lites are considered more sporty, kicks during gear changes are considered signs of a sporty car, qed.

[328iX]

The kicks come from higher pressures in the clutch engagement, same results from a trans tune or shift kit.

Buttery shifts come from a slow engagement or even a slip of the clutch pack.

The ZF changes the shift firmness based off what mode you're in, but depending on the car they can be harder.

[Skyhigh]

The technical reason/method is pretty clear.

My original question however was whether others experience the same as me (especially if they have had the honour to test one of the new 35i-s)

If that is the case in fact, it is also peculiar why BMW would go for that on a high-end 1-Series but not on a high-end 4-series.

Two potential explanations listed already:
- Different gearbox
- Marketing ("M" for the 1 Series)

(The latter should however suggest a similar design feature on the G M340i....)