BMW AG - TIS
RA: Breaking in SAC clutch
Issue status (03/2002)
Break in the friction linings of the clutch by applying light to medium loads, in the same way as for brake linings. This preconditioning creates a carbon layer between lining and metal friction surface which in the end generates the necessary coefficient of friction. Breaking in can take the form of either normal driving with many gearshifts or a specific breaking-in program on gentle gradients.
"Normal" driving will not damage the clutch. "Normal" driving conditions involve drive-off speeds of up to approx. 2500 rpm on a medium gradient, e.g. when driving onto a transporter. Normal driving off on a level surface at speeds up to approx. 2000 rpm are likewise sufficient.
Sporting driving maneuvers will destroy a new clutch! These include driving maneuvers at high differential speeds, overlaps or very high drive-off speeds, e.g. when driving onto a transporter.
When a vehicle is moved "normally", an empirically established figure of approx. 800-1000 gearshifts is applicable to an optimally broken-in lining.
Please conduct the following breaking-in program in order to avoid later customer complaints:
* specifically for M5 and Z8 vehicles
Breaking-in program for approx. 30 km on road
Vehicle subject to "moderate" shifting processes
Drive off at max. 2000 rpm; upshift 1->2, 2->3, 3->4; upshift at 3500-4000 rpm, downshift 4->3, 3->2, 2->1, downshift at 2000 rpm
Drive off 3 to 5 times on a gentle gradient up to approx. 12%, drive-off speed max. 2000 rpm
If you think that's bad, you should try the Centric Posi-Quiet brake pads. Yow what a smell! But it goes away after bedding-in and a few hundred miles, and the pads are super. As I recall, my Tubi exhausts smelled pretty bad on break-in, too. :cheers:Just like breaking in the brake pads... yum yum chemical BBQ smell.
Rich,Can someone clarify the break in procedure "take off at < 2000 RPM" - is that referring to launching? I usually roll off the clutch at 800, just off idle and fully engage well before 1500 RPM. Is that cool with a new clutch and resurfaced flywheel? Also is it necessary to go 1000km, what if I manage to drive the back roads and shift 2000 times in 250 miles?
Clutch party at your place? I could use one done too.
Hmmm, 3 clutch installs in one day. h: I'm game for one per day. Any more than that is no party in my book!same, i'm @ about 90K on this clutch. and it was starting to feel a little soft at the track last year.