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Discussion Starter #1
2002 ST4S is at 24K with original dry clutch. It groans and it is clacketty-clack noisy. I could most likely make it thru next summer, but I'm contemplating replacing. Not sure if OEM or aftermarket is the best way to go.

Up Front:
1. I've never inspected the clutch pack/basket. Never even removed the cover to blow out the dust; however, I vow to do this when the 24k service is done in spring. Finally purchasing an air compressor.

2. Installed aftermarket Evoluzione Slave at 7K. Everything works fine! No issues. Having the new slave and no issues eliminates changing multiple variables at the same time. Installed banjo bleeder at the master when doing the slave upgrade.

3. Riding style is more relaxed sport riding, commuting and some 2-up. Bike has never been 'launched'. Bags regularly used to carry waders, groceries, beer and margarita supplies.

4. Not looking for any bling in the clutch dept.


Concerns:
1. Not being able to find neutral and other mysterious clutch problems after making changes.


Questions for those of you who have changed the clutch basket and/or pack:
1. Where do I start???? Arrrrgh.. The easiest approach seems to be OEM basket and pack. Slam dunk - done. Nearest dealer just closed up shop.

2. What aftermarket setup makes sense? I'm open to suggestions.

3. What is the general OEM versus aftermarket cost for a replacement setup?

Thanks for any comments.
 

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Open the clutch and clean it with or without air.....its very straightforward to do...and in reassembling, do the quiet clutch mod that you'll find well documented in the search.
Its basically adding one more plate to the stack. Works a treat...shut up the clatter completely.....did mine about 5K miles ago...all good.

Colin 02 ST4S
 

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You can purchase aftermarket clutch components for less than stock, and have a little bling. I did not go this way but LT at desmo times sells a good kit among others. Never hurts to lighten the bike up and it will spin up a little quicker ( like you ST4S guys need that) :eek:
 

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I went with a 15/42T sprocket combo on my late 04-ST4s when I purchased it at 6,000 miles. I think this helped increase clutch life, as I did not have to replace the OEM clutch until 42,000 miles. It was noisy but still worked fine;however, the guys at Ducati Seattle said the plates were getting thin. I replaced it with another OEM clutch.
 

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Discussion Starter #5
15/42t

Bill,

Yes. I went that way as well. I miss the increase in speed from an 1/8" of throttle with the 38T rear, but the 42 is nice. I keep telling myself I'm extending the life of the clutch. Your remarks on the 42T rear drove me to give it a try. So far, so good.

Thanks for the comments, all.
 

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I did not have to replace the OEM clutch until 42,000 miles. It was noisy but still worked fine;however, the guys at Ducati Seattle said the plates were getting thin.
Sounds like my clutch...noisy and the friction material is getting a little thin, but it still isn't slipping.......I just rolled 50k miles on that clutch.
 

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Typically, I try the cheaper solutions first. In your case a few minutes of TLC could solve the problem. I would pull the plates off and clean everything up and lube the end of the thrust rod.
 

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I went through the process you are considering last winter when my 2002 ST4s (purchased new from Corse in Saukville -- same as you it seems) reached about 18k. At that time, I was not experiencing any slipping, but the groaning when starting from a stop and the constant clattering finally drove me nuts. I used stock friction and pressure plates, but used a Barnett basket (aluminum with stainless steel inserts at the contact surfaces) to replace the completely toasted stock basket. The clatter is now greatly reduced, and the overall feel remains essentially unchanged to me, which is good.

I also changed (again) the gearing (15/42), put on a new chain (wonderful difference), and lastly installed a much lighter flywheel. It took me awhile, but I've gotten used to the flywheel, which unfortunately requires a much more delicate throttle hand to ride smoothly, as the bike is now extremely responsive to throttle changes (up or down).

Based on my experience (I did the work myself) I would recommend staying with the stock friction and pressure plates and expect to replace the basket. So far, I am pleased with the Barnett basket.

Best regards,
Peter
 

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Mike -

Basket suggestions (for longer life than OE late model aluminum):

1) Pro Cutting 7075 Hard Anodized basket. Call Charlie
Smith at
http://www.procutting.com/aboutus.html for pricing. These used to
come with the friction plate slots machined undersize and required hand
fitting/filing of both edges of all 12 tangs on every
plate (I know, I fitted mine myself instead of paying for the whole pre-
fit clutch pack). I believe he's discontinued the u'size version for a
drop-in model only, used to offer both options.

2) Buy a low mileage (read no notching in slots) used OE steel basket on
Ebay. Don't remember for sure what MY they changed from steel to
aluminum baskets, around '99 or '00 I think.

Clutch pack - Barnett or Ducati OE pack w/ aluminum friction plates. I believe the OE Ducati friction plate tangs are slightly thicker than the Barnett,
which should theoretically increase lifespan/reliability somewhat.

In regard to difficulty finding neutral - There is a very high probability that this is at least in part, if not wholy attributable to the Evoluzione slave cylinder you have installed. All the marketing hype and board/forum discussions of oversize slave cylinders by Ducati owners in search of lighter clutch lever effort rarely discuss the tradeoff - reduced throwout stroke at the clutch pack. Significant reduction in the stroke at the pushrod/clutch pack, combined with "normal" accumulation of friction plate dust, results in less than complete clutch disengagement, in turn resulting in difficulty finding neutral.
You don't specify which size Evoluzione slave cylinder you purchased, but the 28.5 mm diameter model reduces the throwout stroke by 30% for a given amount of hand lever displacement, or stroke. The 30.5 mm model is a 49% reduction. In other words, if the stock master/slave combination yields 2.5 mm (about 0.10")of throwout stroke at the clutch pack for a given amount, or even the full hand lever travel available, the 28.5 mm Evoluzione slave will yield only 1.75 mm (0.07") of throwout stroke. This is a very significant reduction in available friction/driven plate separation distance, almost always causing difficulty in finding neutral.

My '02 4s had the 28.5 mm Evoluzione on it when I purchased it, and I have since replaced it with the OE 25 mm slave. I will also replace the OE 12 x 20 mm master cylinder with a pre '02 13 x 20 to further increase the throwout stroke (approx. 17%), to further increase positive clutch disengagement and make finding neutral less problematic - I am willing to deal with a little heavier lever effort.

Kevin
 

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Correction -

Correction - The change to 12 x 20 mm (conventional, non-radial) master cylinders from 13 x 20 mm occurred in MY '00, not '02.
 

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Discussion Starter #11
Good info

Thanks all. I plan to start with a clutch housing clean-up session in conjunction with the springtime valve adjustment. Heck, as mentioned above, this option is free and easy. When everything is apart I can study it a bit. Right now clutch packs/baskets are a mystery as I've had no hands-on experience.

KNJ - Regarding the search for neutral, currently the bike does not have an issue. All is fine. I understand now your point about several factors influencing clutch disengagement. Your detail is greatly appreciated. I dug out the old paperwork for the Evo Slave. Turns out I purchased it from Motostrano...big dummy. There are no part numbers on the receipt. I don't know if it is a 28.5 or 30.5; however, I suspect it is the 28.5 model. The product did come with some instructions and they say pn 90041/42/43. Hmmmm... The narrative says,'...20% reduction in effort". I did not purchase for an easy clutch lever pull; rather, to replace the failing/leaky OEM slave cylinder.

Peter - So you purchased OEM clutch pack AND a Barnett basket, or did you re-use your OEM clutch pack? Also, bummer about Saukville closing it's doors. I hear the closest Duck shop is in Chicago.

A trick I was advised to try after I purchased the Evo Slave was to use an Evo piston in the OEM slave. A contributor to this list has done this change many miles ago. I would have tried that for $20, but it was too late.

I'll continue to study the suggestions on baskets and packs. Thanks!
 
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