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Discussion Starter · #1 ·
Just wondered if anyone has had any issues or experience with beefing up the 848 clutch for race use. As a new track bike I thought it was a good idea to practice some fast starts. End result is clutch slips. Just hoping for some informed opinion. Cheers
 

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There really isn't anything you can do besides swap clutch plates. I've done hundreds of race starts on my 848 with the wet clutch and it always felt fine. It's far more robust then the dry clutches that I'd burn out very quickly during race starts. When your a good starter, you tend to burn up clutches a lot faster.
 

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This may sound a little 'out of left field', but does the bike still have stock hand levers?

Many replacement levers apply too much preload to the hydraulics. In the case of the clutch this can lead to slippage.

Check that the clutch lever 'pusher' has a slight bit of clearance from the master cylinder piston.

You don't want to burn out another set of clutch plates.
 

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Just wondered if anyone has had any issues or experience with beefing up the 848 clutch for race use. As a new track bike I thought it was a good idea to practice some fast starts. End result is clutch slips. Just hoping for some informed opinion. Cheers
Sounds a bit strange ... did you already checked the system for air?
How many miles?
Wonder about the size of the "worn" clutch plate pack when changed. Minimum of the the clutch plate pack (friction plates + plain steel plates) is 41.6 mm = referring to the workshop manual (848, year 2008).
 

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41.6mm for the stack height on a 848.. interesting.. the stack height on my DP 848 slipper clutch (conversion) is 36.5mm, same as the stack height on my 1098R slipper... wet clutch must use more plates??? Thanks for the info.
 

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Discussion Starter · #9 ·
Having a decent look tomorrow. 2011 evo . Brand new slipper(ducabike) plus clutch pack. 13000 kms

Only second day riding. Yep we are going to check old clutch pack

Thanks for the info. Will post how it went.
 

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Sounds a bit strange ... did you already checked the system for air?
How many miles?
Wonder about the size of the "worn" clutch plate pack when changed. Minimum of the the clutch plate pack (friction plates + plain steel plates) is 41.6 mm = referring to the workshop manual (848, year 2008).
OK ... made a mistake ... damn it :wtf:
Minimum thickness is 46.1mm, not 41.6mm, referring to the workshop manual.
Number of friction and steel plates of a 848_2008 is the same as for a 848_EVO:
11 friction plates (each 2.6mm)
+
10 steel plates (6x 1.6mm + 4x 2.0mm)
=
46.2mm
See attached 527.PDF.

The Duc workshop manual lost 0.1mm while doing the math ;-)


To make it more confusing, take a look on the drawing of the SUTER anti hopping clutch. I got that clutch in my 848 EVO ... works like a charm.
SUTER is talking about min 49.65mm or max 50.45mm, using the original plate pack :ahhh:

Unfortunately I did not made notes when I installed the SUTER clutch. Will check it on the next oil change :D

Wonder what the correct size is (?).

BTW ... referring to the Ducati owners manual, the 848 and even the 848 EVO still got a dry clutch :friday:
 

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Discussion Starter · #12 ·
Thanks Rolle.

We should start on it this arvo and hopefully get some answers.

Cheers
 

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I've got two Ducati's in yee'ol garage, both are apart on different jobs, but I have both clutches on the counter.

The 848 wet clutch measured to be a tiny bit over 50mm thick
The 996 dry slipper clutch measured exactly 40mm thick

So whatever the manual's say, my numbers tend to be a bit more accurate as they came from good working bikes and not a guess.
 

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^^^ Yeah, we've seen your pictures of "yee'ol" garage!!!!.....just sayin.... :shrug:
 

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Discussion Starter · #16 ·
Bit of a report on what we found. First of all thankyou to all the info people posted. The history of the bike was I bought it as a insurance write off and prepared it for the track. In doing so I thought it wise to have someone with Ducati experience service the bike and had the ducabike slipper and new clutch stack installed at the same time. After we checked the lever was working as it should we started on looking at clutch stack height . We measured original and it measured approx 50.5mm The installed stack had a height of 47.5mm. Interesting .We had in the old clutch pack a new uninstalled friction plate . When we put all the plates in to original height 50.5 the the clutch wouldn't function properly. What we ended up doing was swapping all the 4 1.9 mm metal plates for the thinner 1.55 mm metals from the OEM spare pack. This has given us a stack height of 49.1 plus another friction plate that was previously not in. I have not tested properly as yet but but we are quite confident this should solve the issue.
 

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Interesting ... do you got the stock slave cylinder or an after market one?
 

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Discussion Starter · #18 ·
Hey Rolle. It's all stock except the Ducabike slipper. Still Havnt tested it properly yet but it should be an improvement on how it was. Thanks for the pics you posted.
 

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No a problem, thats what a forum is for.

Have you checked Pat's advise (post #4) about the clearance of the master cylinder?
Once you start pulling the lever/clutch you should see a slight rise of the fluid in the reservoir, before the clutch actually opens, better said before you feel a resistance on the lever.
 

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Discussion Starter · #20 ·
Yep just checked it now and yes a very slight rise in fluid as you say. That side still has the original lever on it. I will hopefully get a ride in in the next week or 2 and test properly. Cheers
 
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