Clutch Delay Valve

rye m3 · 12-18-2011, 08:35 PM

Yes, I know a search would reveal that the E92 doesn't have one. However, it has occurred to me that MANY have written about balky shifts from 1st to 2nd (me included). Often, others suggest that maybe the clutch isn't fully engaged. Others have suggested "hesitating" between gears. Well, the clutch PEDAL is always down. However, I'm not so sure about the clutch. Anyone else know how to double clutch? EVEN double clutching I've ground 2nd gear on the 3-2 shift. Indeed, it seems like the clutch was not fully engaged when I hit 2nd.

Long and short of it, seems there could be a clutch delay valve of sorts in the car. Obviously not the same mechanism as the E46. Perhaps also not bypassable. The actuation of the pedal doesn't seem to quite match the clutch. I've read several posters have had full tranny replacements. Doesn't seem like that should be necessary.

I realize this is an old topic, but I wondered if there has been any research on this that I've missed. Read all the old threads I could. Sorry, hesitating while shifting is not a solution, it is just a workaround.

piloto · 12-19-2011, 02:33 AM

Try bleeding the clutch, and try the secondary spring removal trick. Personally, I haven't yet bled the clutch, though will in a couple of weeks, but I did the spring delete and added the ebay clutch stop, and it's now much easier to consistently feel the clutch engagement point, although it's no where near perfect.

I can see how you think there's something akin to a cdv somewhere. The entire clutch engagement has a very non-linear feel to it. I don't know if it's excessive deflection in the clutch fork (i.e. a poor and weak design perhaps), or if the pressure-plate is an akward design of sorts, but something just ins't right.

serranot · 12-19-2011, 04:21 AM

The transmission is less than ideal. There is no real solution. It is what it is.

M_GmbH · 12-19-2011, 04:57 AM

Quote:

Originally Posted by serranot

The transmission is less than ideal. There is no real solution. It is what it is.

Solution = MDCT!

PhillyNate · 12-19-2011, 07:43 AM

I've driven manuals for 20 years and with this manuals faults, linearity being my issue, it does seem extremely durable. IMO

immiketoo · 12-19-2011, 07:48 AM

Quote:

Originally Posted by Aussie335iM

Solution = MDCT!

Here we go...

rye m3 · 12-19-2011, 08:39 AM

I didn't think there was a spring or there was a significant redesign, which limits the benefit on a 2011.

Hope it's durable. Otherwise, sure seems like there is some wear on the 2nd gear synchro. Agree that I'm not sure it is CDV, but something is amiss. All that have had trannies replaced are very happy. Wonder if it is just a design flaw as suggested.

apecush · 12-19-2011, 09:50 AM

Chances are what you are feeling is the dual mass flywheel. Do a google search on how it works, you'll see why it feels considerably different from a conventional flywheel/clutch arrangement.

M_GmbH · 12-19-2011, 08:22 PM

Quote:

Originally Posted by immiketoo

Here we go...

Couldn't resist - Sorry!

rye m3 · 12-19-2011, 09:21 PM

Quote:

Originally Posted by apecush

Chances are what you are feeling is the dual mass flywheel. Do a google search on how it works, you'll see why it feels considerably different from a conventional flywheel/clutch arrangement.

Didn't know that, thanks. Did the reading and I don't get it at all. To dampen low RPM vibrations, usually on diesel engines? Dampen vibrations on luxury cars? Why did they put a DMF in an M3? We should be talking light weight flywheel here! No wonder the throttle response is so muted. Personally, I did not find anything relating to how the clutch would engage differently in a car with a DMF than on with a single.

Were you suggesting a DMF would actually cause a delay in the engagement of the flywheel? I'd be very curious to know what other cars are applying a DMF.

apecush · 12-20-2011, 01:49 AM

the delay (likely...unless your delay is excessive) is due to the compression of one of the circumferential springs in the flywheel. if you've driven a car with a lightweight flywheel and single or multi-disc clutch capable of holding big (500 hp), you would understand why bmw went with the dmf. they had to maintain some semblance of drivability with the system, instead of a soft but barely capable clutch and light flywheel, we got a strong dual plate clutch and dual mass flywheel.

Another performance car using a dual mass flywheel, for example, is the MK4 Supra.

DavidZ · 05-30-2013, 02:43 PM

Well I'll be damned. I always thought my M3 had a CDV like my S2000, just from the way it starts off the line in 1st while loafing around daily driving. It feels like it has softer primary engagement very quickly followed a more solid secondary engagement. I was coming on here to look for CDV bypass reviews.

G80indy · 05-30-2013, 08:35 PM

I am relieved to learn this is one mod I will not have to do when I get my car

12-18-2011, 08:35 PM	#1
rye m3 Lieutenant 33 Rep 489 Posts Drives: 2011.75 E92 M3 Join Date: Apr 2011 Location: New York iTrader: (2)	Clutch Delay Valve Yes, I know a search would reveal that the E92 doesn't have one. However, it has occurred to me that MANY have written about balky shifts from 1st to 2nd (me included). Often, others suggest that maybe the clutch isn't fully engaged. Others have suggested "hesitating" between gears. Well, the clutch PEDAL is always down. However, I'm not so sure about the clutch. Anyone else know how to double clutch? EVEN double clutching I've ground 2nd gear on the 3-2 shift. Indeed, it seems like the clutch was not fully engaged when I hit 2nd. Long and short of it, seems there could be a clutch delay valve of sorts in the car. Obviously not the same mechanism as the E46. Perhaps also not bypassable. The actuation of the pedal doesn't seem to quite match the clutch. I've read several posters have had full tranny replacements. Doesn't seem like that should be necessary. I realize this is an old topic, but I wondered if there has been any research on this that I've missed. Read all the old threads I could. Sorry, hesitating while shifting is not a solution, it is just a workaround. __________________ E92 M3 MR on Red/Black ZCP Sound Carbon 2007 997S - sold 2003 E46 M3 Steel Grey on Red- sold 1997 E36 M3 Arctic Silver on Black- sold
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12-19-2011, 02:33 AM	#2
piloto Captain 28 Rep 843 Posts Drives: 2011 E90 M3 - AW/FR Join Date: Jun 2010 Location: Orange County, CA iTrader: (0)	Try bleeding the clutch, and try the secondary spring removal trick. Personally, I haven't yet bled the clutch, though will in a couple of weeks, but I did the spring delete and added the ebay clutch stop, and it's now much easier to consistently feel the clutch engagement point, although it's no where near perfect. I can see how you think there's something akin to a cdv somewhere. The entire clutch engagement has a very non-linear feel to it. I don't know if it's excessive deflection in the clutch fork (i.e. a poor and weak design perhaps), or if the pressure-plate is an akward design of sorts, but something just ins't right.
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12-19-2011, 04:21 AM	#3
serranot Lieutenant 324 Rep 488 Posts Drives: 2011 E90 M3 6MT Join Date: Mar 2011 Location: Middletown, MD iTrader: (0) Garage List 2011 BMW E90 M3 [10.00]	The transmission is less than ideal. There is no real solution. It is what it is.
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12-19-2011, 07:43 AM	#5
PhillyNate ENTHUSIAST 135 Rep 2,097 Posts Drives: 2010 Porsche Cayman Join Date: Apr 2011 Location: Philadelphia iTrader: (0) Garage List 2010 Porsche Cayman [0.00]	I've driven manuals for 20 years and with this manuals faults, linearity being my issue, it does seem extremely durable. IMO __________________ "what I'm driving here...is an ending." Jeremy Clarkson 2010 Carrara White Porsche Cayman 6mt 2014 Whiteout Toyota GT-86 6mt(Sold 05/23/15) 2011 Alpine White BMW M3 6mt ZCP Coupe(forced retirement 06/06/14) 2008 Alpine White BMW 328i 6mt Coupe(retired 06/21/11)
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12-19-2011, 08:39 AM	#7
rye m3 Lieutenant 33 Rep 489 Posts Drives: 2011.75 E92 M3 Join Date: Apr 2011 Location: New York iTrader: (2)	I didn't think there was a spring or there was a significant redesign, which limits the benefit on a 2011. Hope it's durable. Otherwise, sure seems like there is some wear on the 2nd gear synchro. Agree that I'm not sure it is CDV, but something is amiss. All that have had trannies replaced are very happy. Wonder if it is just a design flaw as suggested. __________________ E92 M3 MR on Red/Black ZCP Sound Carbon 2007 997S - sold 2003 E46 M3 Steel Grey on Red- sold 1997 E36 M3 Arctic Silver on Black- sold
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12-19-2011, 09:50 AM	#8
apecush Lieutenant 30 Rep 521 Posts Drives: 2008 E90 M3 Join Date: Aug 2011 Location: Edmonton iTrader: (2)	Chances are what you are feeling is the dual mass flywheel. Do a google search on how it works, you'll see why it feels considerably different from a conventional flywheel/clutch arrangement.
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12-20-2011, 01:49 AM	#11
apecush Lieutenant 30 Rep 521 Posts Drives: 2008 E90 M3 Join Date: Aug 2011 Location: Edmonton iTrader: (2)	the delay (likely...unless your delay is excessive) is due to the compression of one of the circumferential springs in the flywheel. if you've driven a car with a lightweight flywheel and single or multi-disc clutch capable of holding big (500 hp), you would understand why bmw went with the dmf. they had to maintain some semblance of drivability with the system, instead of a soft but barely capable clutch and light flywheel, we got a strong dual plate clutch and dual mass flywheel. Another performance car using a dual mass flywheel, for example, is the MK4 Supra. Last edited by apecush; 12-20-2011 at 09:26 AM..
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05-30-2013, 02:43 PM	#12
DavidZ Lieutenant 83 Rep 399 Posts Drives: '11.5 E90 M3 6MT Join Date: Apr 2011 Location: Kensington, MD iTrader: (1)	Well I'll be damned. I always thought my M3 had a CDV like my S2000, just from the way it starts off the line in 1st while loafing around daily driving. It feels like it has softer primary engagement very quickly followed a more solid secondary engagement. I was coming on here to look for CDV bypass reviews. __________________ -David
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05-30-2013, 08:35 PM	#13
G80indy Save the Manuals 1714 Rep 2,937 Posts Drives: Z3, E46, G80 Join Date: May 2005 Location: Indy iTrader: (0)	I am relieved to learn this is one mod I will not have to do when I get my car __________________ 2023 G80 6MT, CCBs 2002 330i Dinan, 5MT 2000 Z3 Conforti, 5MT
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