When upshiftng the 6MT, anyone else think engine RPM drops very slowly?

[EndlessssRain]

I am driving a 6MT , i have a problem that i feel the RPMS drop slowly every time i do upshift.

every time i have to wait the RPMS to drop to proper position when i upshift, for example i upshift from red line 7000RPMS of 1st gear to second gear, it is supposed to drop to around 4000RPMS, but it drops very slow .

I saw that the RPMS of other cars drop very fast when upshifting from low gear to high gear .

anyone else experience this issue ? It confuses me a lot, hope someone answer... #_#....

[F30MSport]

Which driving mode are you experiencing this?

I've only experienced rpms dropping too fast when the A/C is on. Not sure if that's normal?

Otherwise RPMs are just right between shifts; balanced...not too fast or slow in comfort/sport but sport + drop faster

[amw896]

some dual flywheels exhibit this behavior as the inertia generated by increasing rpm is not so easy to suddenly stop when you engage the clutch. I had a IS250 that had this issue and it was crazy annoying. I've never heard of this on the m4 though.

[EndlessssRain]

i usually drive in sport mode .
would A/C affec RPM dropping?

[EndlessssRain]

would driving mode affect speed of RPM dropping?

[AJS1000RR]

Originally Posted by EndlessssRain

I am driving a 6MT , i have a problem that i feel the RPMS drop slowly every time i do upshift.

every time i have to wait the RPMS to drop to proper position when i upshift, for example i upshift from red line 7000RPMS of 1st gear to second gear, it is supposed to drop to around 4000RPMS, but it drops very slow .

I saw that the RPMS of other cars drop very fast when upshifting from low gear to high gear .

anyone else experience this issue ? It confuses me a lot, hope someone answer... #_#....

Does it exhibit the same behavior in Sport+?

The slower drop in rpm could be a driving aide (similar to rev match on down shifts). By slowing the rpm drop during shifts, even a less experienced (slower shifting) manual transmission driver will be able to acheive smooth shifts by having more time so to speak to complete the shift.

My ED M4 is on the boat from Germany, so I don't recall the rpm drop behavior in Sport+.

[SMV_M4]

Are you also having issues with revs dropping and then stalling at 2k rpm before finally hitting idle after clutching in or shifting to neutral while at speed? How about harsh vibration or noise coming from the clutch and rest of the drivetrain when manipulating the clutch pedal for shifts up or down? My clutch started having similar problems to what you've described but hey go even further. It's really starting to bother me and the dealership has no fucking clue what it is nor will they even look because the labor cost isn't covered for whet they deem to be a "non-functionality issue."

[woosolow]

Originally Posted by F30MSport

Which driving mode are you experiencing this?

I've only experienced rpms dropping too fast when the A/C is on. Not sure if that's normal?

Otherwise RPMs are just right between shifts; balanced...not too fast or slow in comfort/sport but sport + drop faster

+1 I feel it drops faster with ac on. I think that's normal. The same happened on my e92.

[EndlessssRain]

Originally Posted by AJS1000RR

Does it exhibit the same behavior in Sport+?

The slower drop in rpm could be a driving aide (similar to rev match on down shifts). By slowing the rpm drop during shifts, even a less experienced (slower shifting) manual transmission driver will be able to acheive smooth shifts by having more time so to speak to complete the shift.

My ED M4 is on the boat from Germany, so I don't recall the rpm drop behavior in Sport+.

yes it drop smoothly , but not fast enough

[EndlessssRain]

Originally Posted by woosolow

+1 I feel it drops faster with ac on. I think that's normal. The same happened on my e92.

any reason why would this happen?

[sandwi54]

Yes the RPM drops slowly (but smoothly) when shifting at high RPMs (especially from 1st to 2nd and 2nd to 3rd). That's why BMW offers the DCT as a faster transmission which costs more as an option.

I sold my 6MT M3 a couple of weeks because of my bad knee and also because I felt the 6MT was the bottleneck of the whole car's performance. Everything about the car is so fast and technologically advanced but the 6MT felt like it's holding back the car from achieving its full potential. The 6MT in this car is a great transmission and I loved it, but I felt that it's not a good match to the M3 in terms of overall feel.

[F83]

I have not noticed this however I drive almost exclusively in Sport+ (certainly when driving aggressively and would notice). Not sure if Sport + contributes - just saying that's what I drive and I haven't noticed the issue.

[AJS1000RR]

Originally Posted by sandwi54

I felt the 6MT was the bottleneck of the whole car's performance.

Let's all be honest here, outside of a straight line drag race, the performance bottle neck for most M4's will be the driver :-) not the transmission :-)*

*unless one is a professional racing driver, and able to push the car to the point where the transmission hinders the performance he/she can get out of the car.

[literbikes]

Originally Posted by F83

I have not noticed this however I drive almost exclusively in Sport+ (certainly when driving aggressively and would notice). Not sure if Sport + contributes - just saying that's what I drive and I haven't noticed the issue.

sports+ .... Done. No reason for rev match if you drive a manual.

[sandwi54]

Originally Posted by AJS1000RR

Let's all be honest here, outside of a straight line drag race, the performance bottle neck for most M4's will be the driver :-) not the transmission :-)*

*unless one is a professional racing driver, and able to push the car to the point where the transmission hinders the performance he/she can get out of the car.

It's not about the track performance (and definitely not about drag race which this car is not suitable for). 6MT is fun for the ability to manually clutch and shift in a H pattern, but that's about it. When I want to accelerate fast and change gears at high RPMs, it's annoying that the RPM drops so slowly - that's what's holding back the car's performance.

I'm not debating on 6MT vs DCT (there's a whole other pointless thread on that topic). Just responding to the OP that I observe the same slow RPM drop and stating what I don't like about the 6MT in everyday driving.

[EndlessssRain]

Originally Posted by F83

I have not noticed this however I drive almost exclusively in Sport+ (certainly when driving aggressively and would notice). Not sure if Sport + contributes - just saying that's what I drive and I haven't noticed the issue.

when u are in sport+ , what do you feel about rpm when upshifting 1st to 2nd at 7000rpms? does it drop as fast as the one in this video?

[Alpine300zhp]

Originally Posted by sandwi54

Yes the RPM drops slowly (but smoothly) when shifting at high RPMs (especially from 1st to 2nd and 2nd to 3rd). That's why BMW offers the DCT as a faster transmission which costs more as an option.

I sold my 6MT M3 a couple of weeks because of my bad knee and also because I felt the 6MT was the bottleneck of the whole car's performance. Everything about the car is so fast and technologically advanced but the 6MT felt like it's holding back the car from achieving its full potential. The 6MT in this car is a great transmission and I loved it, but I felt that it's not a good match to the M3 in terms of overall feel.

I agree. I was a strictly 6MT buyer with BMW's up until the F generation cars came out. I purchased an F10 with 6MT and it was horrible. I drove other F generation 6MT cars and hated them. BMW has made it such that the car is built around the DCT or the auto and opting for the 6MT guarantees the driver an inferior experience. The slow RPM drop was one of many features that I hate about the current 6MT cars....

[sandwi54]

Originally Posted by Alpine300zhp

I agree. I was a strictly 6MT buyer with BMW's up until the F generation cars came out. I purchased an F10 with 6MT and it was horrible. I drove other F generation 6MT cars and hated them. BMW has made it such that the car is built around the DCT or the auto and opting for the 6MT guarantees the driver an inferior experience. The slow RPM drop was one of many features that I hate about the current 6MT cars....

I'm glad I'm not the only one who thinks that. The 6MT in this car is a great transmission and well designed - I enjoyed every moment of shifting it during my 20 months of ownership. However, it's simply mismatched to the F8x and better suited for a lower performance car such as a 328i.

I'm glad BMW offered the choice of 6MT and DCT and gave me the opportunity to own both and understand the advantage and disadvantage of each.

[clutchdj]

Originally Posted by EndlessssRain

i usually drive in sport mode .
would A/C affec RPM dropping?

Yes because you are adding more load to the motor once the ac compressor engages. Like others have said very normal.

[clutchdj]

Originally Posted by sandwi54

I'm glad I'm not the only one who thinks that. The 6MT in this car is a great transmission and well designed - I enjoyed every moment of shifting it during my 20 months of ownership. However, it's simply mismatched to the F8x and better suited for a lower performance car such as a 328i.

I'm glad BMW offered the choice of 6MT and DCT and gave me the opportunity to own both and understand the advantage and disadvantage of each.

I know what you mean the 6mt has to be shifted with a bit of m3ntal precision in (sport+) order to get it right when rowing up the gears or the drivetrain lash will knock on your door. Heel toeing down the gears as well; 3rd needs a proper blip because 2nd is pretty tall. It sounds like the issue you were experiencing is mostly due to the auto rev matching on the downshift in regular sport mode (even if you've heel toe'd in regular sport throttle mode). The whole experience is a bit unnatural but not annoying (for me). I like to think of it as a lazy mans gearbox until you get into sport+ mode. My only complaint is the throttle is a bit unnatural in s+ (pedal to throttle body ratio); but nothing is perfect. The best manuals I've driven are the 944's up to the late model Pcars before drive by wire.

In any case did you stay with BMW and just go DCT?

[stuggy]

Originally Posted by sandwi54

I'm glad I'm not the only one who thinks that. The 6MT in this car is a great transmission and well designed - I enjoyed every moment of shifting it during my 20 months of ownership. However, it's simply mismatched to the F8x and better suited for a lower performance car such as a 328i.

I'm glad BMW offered the choice of 6MT and DCT and gave me the opportunity to own both and understand the advantage and disadvantage of each.

I agree with this statement to a degree. I think it's the torque management system that really takes away from the 6mt experience in this car.

[BMW335iOn18s]

Can anyone else chime in? Does the S55 have rev hang?

I know my N55 doesn't, and my car is totally stock.

If the S55 is the same as the N55 (I hope it is) there should be very little to no rev hang.

Cars that have it the worst are the VW 2.0 tsi and the 8th generation Honda Civic Si. If you go on YouTube you can find plenty of videos.....

Thank goodness BMWs aren't ANYWHERE NEAR that bad....it's pretty much non existent on all of the 6 speed N54/N55s I've driven...

Incase anyone is curious as to why this occurs, it has NOTHING to do with dual mass flywheels.

BMW and other automakers program this rev hang into their drive by wire software to prevent the throttle from closing too quickly and letting unburnt fuel into the exhaust. This is how modern cars do a great job of controlling emissions. It's noticeable on manual cars because you push the clutch in and it's as if the revs are sticky....it's really annoying on FWD cars especially.