Clutch / Gearbox

[shimmy]

Originally Posted by outnumbered

That's a good point. There was a lot of discussion about this 2-3 years ago over on mtorque/bm3w and I think it resulted in pretty much every CSL in the country spending a day at Murketts !

very true of must internet issues but clutch slur is not one of them..........its real

[weedavey]

Heres me in mine.


When Engine Cold (shift speed): s3
When Engine at operating temp (shift speed): s6
Shift speed used at track : NOT YET
Lift on upshift: No
Lift on downshift: sometimes
Full throttle redline upshifts periodically: yes
Part throttle redline upshifts : never
Launch Control use: never
Software reset period: Not yet.

[Dan]

Originally Posted by NZ_M3

I have personally NEVER experienced the so called 3rd to 4th gear slur.

First is a soft clutch reset (I suspect this is the same as the drive above 30mile/h, in neutral and pull both paddle back reset) - it reinitialises the system vis-a-vis the wheel speed rotation sensors.

When Engine Cold (shift speed): s3
When Engine at operating temp (shift speed): s4
Shift speed used at track : s5 or sometimes s4
Lift on upshift: No
Lift on downshift: sometimes
Full throttle redline upshifts periodically: yes
Part throttle redline upshifts : never
Launch Control use: never
Software reset period: usually every two to three weeks

Some great info as usual there mate

Mine seems to 'slip' into 5th & 6th gear, rather than 3rd to 4th Gear, it usually happens at full throttle, I can make it better by slightly lifting when upshifting but seeing as that car should already be doing this for me I would like to keep the throttle nailed!

Can you give any more details on the 'Soft Clutch Rest', is it simple as it sounds, go above 30mph, knock the car into neutral and pull both paddles back?

Finally to give some further info this is my take on use:

When Engine Cold (shift speed): S5
When Engine at operating temp (shift speed): S5
Shift speed used at track : Not been on track yet
Lift on upshift: Sometimes
Lift on downshift: Yes, usually
Full throttle redline upshifts periodically: No
Part throttle redline upshifts : No
Launch Control use: Never
Software reset period: None whilst in my ownership (3-4 months now)

[thegingerninja]

Mine has never had any issues, just follow these steps:

always change gear with your foot to the floor - this may sound nuts, but it is very easy. If I want a nice steady drive, I change gear at 1500prm with the throttle at 100%. This makes the computer software register a 100% open throttle gear change and thus the clutch release duration is kept to a minimum (i.e. no slurring) You have to imagine what the computer "thinks" as you ask it to change gear. Just go through your mind how you would drive a manual car. If you want a nice smooth gear change, you release the clutch pedal gently. The CSL software will self learn the way you drive the car - so lifting between gear changes will cause slurring.

This is the reason why most people find their cars are brilliant after a thrashing on a trackday, but it tails off in coming months after that.

If you only allow the computer software to register 100% open throttle gear changes, it will release the clutch quicker all the time.

I have doing this now for nearly 4 years - gear changes are so good I only ever use S4. S6 almost snaps my head off! Most other people who have tried this also report that after a short period the clutch slur goes, provided it wasn't completely buggered before.

In most cases of slurring - clutches have been found be well within tollerances. It's the transfer onto the flywheel that does it.

[wazadaza]

Great advice as ever! Does anyone know how much BMW charge for these resets and software upgrades on the box?

[weedavey]

Originally Posted by thegingerninja

Mine has never had any issues, just follow these steps:

always change gear with your foot to the floor - this may sound nuts, but it is very easy. If I want a nice steady drive, I change gear at 1500prm with the throttle at 100%. This makes the computer software register a 100% open throttle gear change and thus the clutch release duration is kept to a minimum (i.e. no slurring) You have to imagine what the computer "thinks" as you ask it to change gear. Just go through your mind how you would drive a manual car. If you want a nice smooth gear change, you release the clutch pedal gently. The CSL software will self learn the way you drive the car - so lifting between gear changes will cause slurring.

This is the reason why most people find their cars are brilliant after a thrashing on a trackday, but it tails off in coming months after that.

If you only allow the computer software to register 100% open throttle gear changes, it will release the clutch quicker all the time.

I have doing this now for nearly 4 years - gear changes are so good I only ever use S4. S6 almost snaps my head off! Most other people who have tried this also report that after a short period the clutch slur goes, provided it wasn't completely buggered before.

In most cases of slurring - clutches have been found be well within tollerances. It's the transfer onto the flywheel that does it.

Another method for me to try, thanks.

[Dan]

Originally Posted by thegingerninja

Mine has never had any issues, just follow these steps:

always change gear with your foot to the floor - this may sound nuts, but it is very easy. If I want a nice steady drive, I change gear at 1500prm with the throttle at 100%. This makes the computer software register a 100% open throttle gear change and thus the clutch release duration is kept to a minimum (i.e. no slurring) You have to imagine what the computer "thinks" as you ask it to change gear. Just go through your mind how you would drive a manual car. If you want a nice smooth gear change, you release the clutch pedal gently. The CSL software will self learn the way you drive the car - so lifting between gear changes will cause slurring.

This is the reason why most people find their cars are brilliant after a thrashing on a trackday, but it tails off in coming months after that.

If you only allow the computer software to register 100% open throttle gear changes, it will release the clutch quicker all the time.

I have doing this now for nearly 4 years - gear changes are so good I only ever use S4. S6 almost snaps my head off! Most other people who have tried this also report that after a short period the clutch slur goes, provided it wasn't completely buggered before.

In most cases of slurring - clutches have been found be well within tollerances. It's the transfer onto the flywheel that does it.

That must be hard to comprehend, so accelerator FLAT to the floor regardless of whether or not your changing gear at 1500rpm or 8000rpm!?

I've just been out in mine and given it a pasting for around 35 miles, basically changed quick as I could in all gears, varied throttle positions and not a bloody thing, no slur at all and even on occasions flooring it in second to the redline through the gears it really went well, banging into gear and got my pulse racing!

Originally Posted by wazadaza

Great advice as ever! Does anyone know how much BMW charge for these resets and software upgrades on the box?

I spoke to Andy at Murkett's yesterday and he advised it was £45 for a software update

[weedavey]

Originally Posted by thegingerninja

Mine has never had any issues, just follow these steps:

always change gear with your foot to the floor - this may sound nuts, but it is very easy. If I want a nice steady drive, I change gear at 1500prm with the throttle at 100%. This makes the computer software register a 100% open throttle gear change and thus the clutch release duration is kept to a minimum (i.e. no slurring) You have to imagine what the computer "thinks" as you ask it to change gear. Just go through your mind how you would drive a manual car. If you want a nice smooth gear change, you release the clutch pedal gently. The CSL software will self learn the way you drive the car - so lifting between gear changes will cause slurring.

This is the reason why most people find their cars are brilliant after a thrashing on a trackday, but it tails off in coming months after that.

If you only allow the computer software to register 100% open throttle gear changes, it will release the clutch quicker all the time.

I have doing this now for nearly 4 years - gear changes are so good I only ever use S4. S6 almost snaps my head off! Most other people who have tried this also report that after a short period the clutch slur goes, provided it wasn't completely buggered before.

In most cases of slurring - clutches have been found be well within tollerances. It's the transfer onto the flywheel that does it.

I have just tried this. This morning i went out and from the get go was using 100% foot to the floor shifting on upshifts (bit harsh in the lower gears) . Regardless of revs foot was to the floor.
Problem solved............................................ ...................................
for the majority of my outing.

After the car had warmed up i selected S6 and remained changing at foot to floor. after a while i noticed a slight hesitation at around 5500rpm this was followed by more and more sluggish changes so eased back and changed to i think it was s4, Problem gone again!?!?

My question is does the software learn different driving styles in different modes?

I didn't select th s6 mode again as i was nearing home and steadily cooloing calming down for parking up and switching off. Will be experimenting again next time i'm out but for the first part of this drive the car felt sharp, crisp and precise.

TRY IT.

[SpineOnABap]

Not sure about only changing with 100% throttle openage, even if it is low RPM you've still gotta mash it - would get interesting in the village particularly in traffic in 1st or 2nd

Someone posted that they drive like that AGES ago on Mtorque/BM3W - Ninja it's not you is it? (Simon?)

[Dan]

Originally Posted by SpineOnABap

Not sure about only changing with 100% throttle openage, even if it is low RPM you've still gotta mash it - would get interesting in the village particularly in traffic in 1st or 2nd

That's what I can't seem to get a grasp off, don't think I'll try it tbh