SquidBusters Archive - Ducati Monster Clutch Spring Replacement

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Ducati Monster Clutch Spring Replacement - easy
(Click here to view the original thread with full colors/images)

Posted by: Falcn

We noticed that the monster suffered from the same malody as the VFR - weak OEM clutch springs that would let the clutch slip a good bit when you were taking off from a start, and had let the lever out. There was very little clutch lever friction zone "feel" because of this. Despite the weak springs the clutch pull force was pretty high due to the spring loading of the OEM slave cylinder and its relatively small bore. The Pantera Racing Slave Cylinder took care of the high force, now it was time to fix the slipping before it took its toll on the clutch pack.

This bike had 3,000 or so mile on it when this operation was performed.

Tools needed:
4mm allen wrench/socket. T-handle or Ratchet Socket type of good quality recommended
5mm allen wrench. T-Handle recommended
Low range torque wrench (~5 ft-lb [60 in-lb.] capable)

Parts Needed:
Barnett or other aftermarket spring kit
High Temp chemical resistant gasket maker (OEM or other)

Start by cleaning around the engine side cover if the engine is dirty - you don't want anything getting inside your engine once the side cover is off the bike.

Use the 5mm allen wrench to remove the bolts from the side cover. Keep track of where they are from on the case - as they are different lengths on the top 1/3 of the cover.

The cover should remove pretty easily - just be sure to pull from both side evenly. I cheated and took out the oil fill plug and hooked a finger inside the cover.

Check the inside of the cover for caked on grime (shouldn't be any on low mile bikes) Clean if needed. Inspect the clutch protector plate bolts to make sure they are not backing out.

I should post a comparison of the VFR clutch vs. this Ducati Clutch - and you'd see a big difference! The Duc has an enclosed oil pump that does not allow you to check gear lash.

Now is a good time to inspect the basket ears and clutch plate tabs. Check for any scoring or wear. If either is worn you have bigger problems than weak clutch springs.

Ducati Clutch

1998 VFR800 Clutch

This next shot is for comparison with the clutch lever pulled in and the clutch disengaged. This shows the clutch fully engaged.

This shot shows the clutch lever pulled in and the clutch pressure plate backed away from the clutch pack.

Here you can see the comparison of the stock pressure plate spring and retainer with the new Barnett spring and retainer. Not as much of a difference as the VFR OEM to Barnett spring length. Actually the Barnett spring is a little bit shorter.

Clutch Pressure Plate Spring Comparison
Height:
Old (mm):41.7
New (mm):39.55

Coil Wire Thickness
Old (mm): 2.53
New (mm): 2.73

After almost breaking my T-handle wrench busting loose the little 5mm-.80 bolts (someone with an air ratchet must have put them on "by hand") we switched out the springs one-by-one. We had to use an easy-out on one as it stripped rather than break loose. Socket cap bolts work well with the "drill" type easy outs. We had a replacement bolt of correct size and pitch to replace the offending OEM one.

After replacing 4 of the 6 springs we decided to check the clutch pull. PROBLEM! The new clutch spring retainers were WAY too shallow and compressed the springs almost 100% - not allowing the clutch to function at all.

Check the spring recess ears on the pressure plate for wear through or cracking when you have the spring and retainer out.

We easily swapped out the Barnett spring retainers for the OEM spring retainers and finshed the spring installation.

Kristen sent an email to the dealer that she got the spring kit from to inquire about the issue with the retainers. I expect we'll have to have a dialogue with Barnett to get any kind of answer as to why they don't work on the bike listed. Maybe they were packaged wrong.

The next two shots show how much more compressed the clutch springs are with the Barnett retainers.

After the spring are switched out and the bolts tightened down to 5 ft-lb (60 inch-lb.) you are ready to button the engine back up. Check the clutch operation one more time to verify everything is working smoothly.

Clean off the old gasket maker material and use your new tube to put down a bead on the lip of the cover. Be sure to go all the way around any bolt holes. Don't go crazy putting this stuff on, a 1/8" wide bead is all that is needed.

Bolt everything back up - be careful not to overtighten the engine side cover bolts - they are steel and the engine case is aluminum - they will strip very easily. Just past hand tight is good (I think the book listed 6 ft-lb).

This did make a noticable difference in clutch grabbing strength - the clutch was much more positive in engagement once the lever was past the friction zone. There is now a more discernable friction zone as well.

This might even improve gas mileage a little.

Posted by: Steve

Very nice... Man, that Monster is definitely getting the subtle upgrades. When's the suspension getting Ohlins valves?

Posted by: mangeldbug

Quote:

Originally Posted by Falcn

We had to use an easy-out on one as it stripped rather than break loose. Socket cap bolts work well with the "drill" type easy outs. We had a replacement bolt of correct size and pitch to replace the offending OEM one.

I love how almost an hour of "CRAP!" became 3 sentences. Actually, once we got the easy-out bit from the hardware store, there wasnt much drama. It came out very nicely. Still, I hate making an emergency run to the store at 8:15pm.

Ryan keeps mentioning that I should get Ti valves...

Posted by: Falcn

Quote:

Originally Posted by mangeldbug

Believe me as far as "maintenance drama" goes - that was VERY minor. If I'd have had the easy out kit I used to have before this would have taken maybe 5 minutes.

And that's OVERSIZE Ti valves.

Posted by: 87hurricane

Bah, wouldn't be a proper job if something hadn't gone wrong. At least that was an easy fix. This reminds me, I've been considering some Barnett clutch springs for a while now. My stock clutch isn't slipping or anything, but I am putting quite a bit of power through it, and I'd like it to last as long as possible. I may have to do the same "mod" sometime soon.

Posted by: Falcn

Quote:

Originally Posted by 87hurricane

Bah, wouldn't be a proper job if something hadn't gone wrong. At least that was an easy fix. This reminds me, I've been considering some Barnett clutch springs for a while now. My stock clutch isn't slipping or anything, but I am putting quite a bit of power through it, and I'd like it to last as long as possible. I may have to do the same "mod" sometime soon.

It feels kind of freaky still since there was no blood shed during this job either, not even a scraped knuckle.

Posted by: 87hurricane

Oh no, that means you're really in for it next time. You need to give the bike at least a little blood sacrifice to keep the peace.

Posted by: Oxi-Rider

You are officially talking me out of getting a Ducati the next time I am in the market for a bike.

Posted by: Falcn

Why is that? This is the same problem the VFR's have from the factory.

We didn't have to change the plugs/wires like we did.
We didn't have to change the clutch slave.

Posted by: Oxi-Rider

You HAD a clutch that was slipping with a low milage bike. You bike ran better when you changed out OEM wires...

Posted by: 87hurricane

Yeah, I kinda see that as an issue. I like something with a little character, and I like to tinker, but I prefer it to be on my terms. I like to mod stuff cause I want to make it better, not because I'm afraid it will fail. That being said, I have to wonder how much of your clutch slippage was due to the bike sitting around with almost no miles on it, that can be hard on clutches too.

Posted by: Falcn

Dunno - it was sitting basically for 4 years. 500 miles per year if you average it.

Posted by: BlackB12

Come on guys, it's falcn. He mods for the sake of modding! Sometimes it even needs fixing! j/k

Posted by: Falcn

This probably wasn't going to be a big issue right away - just like it wasn't on the VFR for many 10's of thousands of miles. After seeing how much of a difference that the new springs made on the VFR clutch feel, and what not changing them from the get-go could eventually do - we thought this was a good idea.

If a non-tinkering person bought the Duc (many do) they wouldn't have to make these changes. If I didn't already have a bike with a hydraulically actuated clutch that taught me about the issues I mentioned I'd have been happily oblivious.

Posted by: VonKujo

Quote:

Originally Posted by BlackB12

Come on guys, it's falcn. He mods for the sake of modding! Sometimes it even needs fixing! j/k

Posted by: mangeldbug

Quote:

Originally Posted by Oxi-Rider

You bike ran better when you changed out OEM wires...

Wouldnt aftermarket spark plug wires with a better core material make any bike run a little better and give it a little better gas mileage?

Posted by: Oxi-Rider

Quote:

Originally Posted by mangeldbug

Wouldnt aftermarket spark plug wires with a better core material make any bike run a little better and give it a little better gas mileage?

Not really in my opinion. Especially on wires that quite new and hardly used. OEM's usually have pretty high quality parts, but in your case, it doesn't sound that way, which makes me wonder about the rest of the bike, you know? Don't get me wrong, I have never worked on a Ducati, and I lust after them, but this sure sounds a little low quality to me.

Posted by: natrona848

what no slipper clutch

Posted by: mangeldbug

Quote:

Originally Posted by Oxi-Rider

I dont really know anything about spark plug wires, but I know this mod wasnt needed. A big reason Ryan got the blue for me because he thought it would look neat with my proposed color change in the future. And any possibility of better gas mileage is always a plus.

Posted by: mangeldbug

Anyway, isnt this what Ducati owners do? Just sit around and mod their bikes??

Im just trying to live up to the image.

Posted by: 87hurricane

If thats the case you need to spend alot more money, I reccomend a factory Termignioi (sp?) carbon exhaust.

Posted by: Falcn

Hmm I think titanium oversize valves and carbon fiber gas tank.

Posted by: Oxi-Rider

And Ohlins road and track forks....

Posted by: Falcn

Carbon fiber rims too.

Posted by: 87hurricane

CF rims

Posted by: 87hurricane

Oh yeah, and some of those new Carbon ceramic rotors, to go with your new Brembo calipers.

Posted by: mangeldbug

OK, to get back on topic:

I contacted Evoluzione about the clutch spring retainers that were included in the spring kit. Apparently they sent me the Barnett spring kit for a Duc dry clutch. Springs are the same, but the spring retainers are different. Using the OEM spring retainers solves the problem encountered when we used the shorter Barnett retainers so Im not going to bother trying to get them to send me the correct parts. You cant see them anyway.