Would like some advice on my clutch

Ross Miller · Post by **Ross Miller** » Wed Sep 05, 2018 10:11 pm

Hi everyone, last week I bought my dream car and as much as I am in love, I'd like to know if the clutch is like this in all ///M's.
I viewed a few Z4M's before purchasing mine but they were all private sellers and understandably preferred not to let a complete stranger test drive their car (i wouldnt either). My question is, is the clutch this sharp in all ///M's? it seems like theres barely a bite to it, like its either engaged or not, on or off.....no in-between. Im getting used to it but the 1st into 2nd change is still a little jolting if its anything but prefect.

Hope I'm describing this well enough.

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mr wilks · Post by **mr wilks** » Wed Sep 05, 2018 10:12 pm

First step would be removal of cdv , welcome to the forum

M M M · Post by **M M M** » Wed Sep 05, 2018 10:18 pm

Yep, remove the CDV. Transforms the drive and I'm surprised they haven't all been done by now!

Ross Miller · Post by **Ross Miller** » Wed Sep 05, 2018 10:33 pm

M M M wrote: ↑Wed Sep 05, 2018 10:18 pm Yep, remove the CDV. Transforms the drive and I'm surprised they haven't all been done by now!

mr wilks wrote: ↑Wed Sep 05, 2018 10:12 pm First step would be removal of cdv , welcome to the forum

just did a little research on what a CDV is and I'm so happy, I thought it was me being a terrible driver but this thing seems so stupid. thanks guys

Gazza51 · Post by **Gazza51** » Wed Sep 05, 2018 10:36 pm

Your description would not be caused by a CDV.

Simon 3.2M · Post by **Simon 3.2M** » Wed Sep 05, 2018 11:03 pm

Sounds normal mate , just need to get used to it. My clutch seems binary almost as thought I'm on the throttle before it's engage which causes a jolt. Simple solution - go onto the throttle a split second later

BTW, I've removed my CDV which made a big difference.

Mangozac · Post by **Mangozac** » Thu Sep 06, 2018 3:26 am

Sounds normal. Removal of the CDV helps a little but it will still have that "on/off" characteristic...

Vanne · Post by **Vanne** » Thu Sep 06, 2018 9:07 am

wait, you bought the car without a test drive?? WTH?? seller didn't want a potential buyer to drive the car? how on earth would you sell a car then??

clutch varies from car to car. my current one has about 1cm from on to off, previously about 2 inches. my mates also has 2 inches of engagement.

Mangozac · Post by **Mangozac** » Thu Sep 06, 2018 10:32 am

Vanne wrote: ↑Thu Sep 06, 2018 9:07 am wait, you bought the car without a test drive?? WTH?? seller didn't want a potential buyer to drive the car? how on earth would you sell a car then??

I missed that bit! Crazy indeed!

Bodyboarder · Post by **Bodyboarder** » Thu Sep 06, 2018 11:07 am

Ive never let a perspective buyer drive my car .... if it’s a good car you can tell and every car I’ve sold has gone to the first person who’s looked at it . It’s just not worth the risk / hassle if anything were to happen

Oh and get that cdv removed ... it made a world of difference to my car !

Bing · Post by **Bing** » Thu Sep 06, 2018 9:25 pm

Mangozac wrote: ↑Thu Sep 06, 2018 10:32 am
Vanne wrote: ↑Thu Sep 06, 2018 9:07 am wait, you bought the car without a test drive?? WTH?? seller didn't want a potential buyer to drive the car? how on earth would you sell a car then??
I missed that bit! Crazy indeed!

I didn’t drive mine before I bought it... but I had no reason to question the history because I bought it from a friend who was the first owner.

Ewazix · Post by **Ewazix** » Thu Sep 06, 2018 9:52 pm

So the CDV makes clutch engagement HARSHER and removing it will smooth progress? Thats not quite how a hydraulic clutch DELAY valve works

its literally a slow release valve,
A worm clutch with limited travel is just that.
I'd suggest bleeding the clutch hydraulics then if its no better getting a quote for a clutch or you are not going to get the best from your car.

-Tom- · Post by **-Tom-** » Thu Sep 06, 2018 10:25 pm

I didn’t test drive my M, nor my previous si

I’ll add to the above in agreement. It sounds normal. It can be a bit of a pig around town and in traffic to be honest, but when you get used to it; and especially when you hook it up properly with your foot down, it will all make sense. Enjoy!

mmm-five · Post by **mmm-five** » Thu Sep 06, 2018 10:34 pm

Maybe ‘smoothing’ is the wrong word, but all it does is delay the clutch’s full disengagement so that you lift off the clutch pedal, floor the throttle and then kangaroo (from a standstill) or hear/feel the clutch slip a little (on full bore, light lift gear changes) as you realise that the CDV hasn’t quite fully released its hold yet.

The removal means the driver is fully in control of both pedals and can judge for themselves when there’s enough bite to launch it without slipping/burning the clutch - which enables a ‘smoother’ launch.

But that’s the way BMW designed it so that the clutch/flywheel takes the damage from ‘energetic’ launches rather the the rest of the drive train.

mr wilks · Post by **mr wilks** » Thu Sep 06, 2018 10:37 pm

mmm-five wrote: ↑Thu Sep 06, 2018 10:34 pm Maybe ‘smoothing’ is the wrong word, but all it does is delay the clutch’s full disengagement so that you lift off the clutch pedal, floor the throttle and then kangaroo (from a standstill) or hear/feel the clutch slip a little (on full bore, light lift gear changes) as you realise that the CDV hasn’t quite fully released its hold yet.

The removal means the driver is fully in control of both pedals and can judge for themselves when there’s enough bite to launch it without slipping/burning the clutch - which enables a ‘smoother’ launch.

But that’s the way BMW designed it so that the clutch/flywheel takes the damage from ‘energetic’ launches rather the the rest of the drive train.

That must be the best explanation yet

its definitely not imagination that removal improves engagement & those who think it is should maybe try one directly before & after before they make comment .

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