Clutch Adaptation - Hot or Cold Transmission?

GregorFuk · 17-09-2015, 04:46 PM

So I *think* I’m experiencing some clutch slur. I have a relatively new clutch and flywheel ~25K so I don’t think they are the issue.
I have a copy of GT1 and last night I the following.

Teach in Clutch valve values;
Teach in Clutch slipping point;
Reset Clutch Curve;

I ran these routines as they are what’s advised if you do any clutch work. I have no gear selection issues so saw no reason to run a full adaptation.
I ran the routines with the car stone cold, the routines ran fine and taking the car out for a spin the gear changes were noticeably snappier. However, as the car warmed things started to get degrade. So my question. Am I supposed to do the clutch adaptations with the engine / transmission up to temp or stone cold.

I did a bit of Googling and there are comments made on M5 forum by a guy who seems to know his stuff. He is a clear advocate for doing the adaptations when warm. What’s the consensus here? And is a redoing the routine whilst warm worth a try?

**portlandgrey** · 18-09-2015, 12:36 AM

I think the correct way is engine stone cold & car on level ground, with the car hooked up to a battery charger.

I've done mine a couple of times with GT1 & always run a full adaptation with no issues, though some on the cutters forum have had problems with the process freezing, leaving the car undriveable.

GregorFuk · 18-09-2015, 12:44 AM

I thought the same. Stone cold etc etc but I wonder if doing it when warm will give better results. I can't see that it would hurt to try it as I can always redo it again.

NZ_M3 · 18-09-2015, 05:42 AM

Warm ... Always warm not stone cold - it's not a valve adjustment.

I've tested this numerous times and if you do it stone cold it always starts doing something funny when the car is warmed up.

The measurements the system takes should be relevant to the actual condition that it experiences - i.e. not when the car is stone cold.

How many times have you heard a F1 engineer tell the drivers to reset their clutch bit point with the car stone cold? Never. That's not how these systems work.

GregorFuk · 18-09-2015, 10:12 AM

Quote:

Originally Posted by NZ_M3

Warm ... Always warm not stone cold - it's not a valve adjustment.

I've tested this numerous times and if you do it stone cold it always starts doing something funny when the car is warmed up.

The measurements the system takes should be relevant to the actual condition that it experiences - i.e. not when the car is stone cold.

How many times have you heard a F1 engineer tell the drivers to reset their clutch bit point with the car stone cold? Never. That's not how these systems work.

Thanks for this. This is what makes sense to me but I kept reading that it had to be done cold. I'll re-do it tonight with the car and transmission fully warmed up.

GregorFuk · 18-09-2015, 09:11 PM

Cheers all. Took the CSL to work today and when I got home I redid the sequences with the car up to temp. Took it for a spin and it's back to its best.

17-09-2015, 04:46 PM	#1
GregorFuk S5 - Full Throttle Join Date: Nov 2014 Posts: 318 Casino cash: $11097	Clutch Adaptation - Hot or Cold Transmission? So I think I’m experiencing some clutch slur. I have a relatively new clutch and flywheel ~25K so I don’t think they are the issue. I have a copy of GT1 and last night I the following. Teach in Clutch valve values; Teach in Clutch slipping point; Reset Clutch Curve; I ran these routines as they are what’s advised if you do any clutch work. I have no gear selection issues so saw no reason to run a full adaptation. I ran the routines with the car stone cold, the routines ran fine and taking the car out for a spin the gear changes were noticeably snappier. However, as the car warmed things started to get degrade. So my question. Am I supposed to do the clutch adaptations with the engine / transmission up to temp or stone cold. I did a bit of Googling and there are comments made on M5 forum by a guy who seems to know his stuff. He is a clear advocate for doing the adaptations when warm. What’s the consensus here? And is a redoing the routine whilst warm worth a try?

18-09-2015, 12:36 AM	#2
portlandgrey S4 - Getting the hang of it Join Date: Jan 2010 Posts: 153 Casino cash: $8449	I think the correct way is engine stone cold & car on level ground, with the car hooked up to a battery charger. I've done mine a couple of times with GT1 & always run a full adaptation with no issues, though some on the cutters forum have had problems with the process freezing, leaving the car undriveable.

18-09-2015, 12:44 AM	#3
GregorFuk S5 - Full Throttle Join Date: Nov 2014 Posts: 318 Casino cash: $11097	I thought the same. Stone cold etc etc but I wonder if doing it when warm will give better results. I can't see that it would hurt to try it as I can always redo it again.

18-09-2015, 05:42 AM	#4
NZ_M3 S5, Sport On, DSC M-track Join Date: Jun 2008 Location: Auckland, New Zealand Posts: 1,434 Casino cash: $13579	Warm ... Always warm not stone cold - it's not a valve adjustment. I've tested this numerous times and if you do it stone cold it always starts doing something funny when the car is warmed up. The measurements the system takes should be relevant to the actual condition that it experiences - i.e. not when the car is stone cold. How many times have you heard a F1 engineer tell the drivers to reset their clutch bit point with the car stone cold? Never. That's not how these systems work.

18-09-2015, 09:11 PM	#6
GregorFuk S5 - Full Throttle Join Date: Nov 2014 Posts: 318 Casino cash: $11097	Cheers all. Took the CSL to work today and when I got home I redid the sequences with the car up to temp. Took it for a spin and it's back to its best.