[BillV]

I don't visit this thread very often but the previous posts suggest that the pdf is no longer available from it's original source. I have it available here.

 

[BillV]

With regard to the different driven plate thickness, you'll see the same thing on page 3-96 of the service manual. Except there it's the outermost plate vs. next to the outermost in the fiche. I have two guesses regarding what it's about and both relate to pack thickness. One is that there's a target thickness when new and the varying thickness allows you to better reach it. The other is that it allows you to compensate for wear on the drive plates. It's been in the service manual from the beginning so it's not a part update.

P.S. Please measure the plates in the kit when you get it and report back here. It's my impression that the kit includes the springs, drive plates, driven plates, and the cover gasket.

 

[BillV]

How about the thicknesses of the steel plates?

 

[BillV]

As mentioned the pdf is just JetSpeedz's instructions from the front of this thread. Still it's oftentimes helpful to have it in that form. Here it is.

 

[BillV]

There's a slightly more readable version of the pdf here. It's the one labeled "Clutch mod.unlocked & fixed.pdf". Some minor errors were also fixed. It may look funny with overlaid text on their viewer. But it's fine once downloaded.

 

[BillV]

^This doesn't answer your question but is semi related. Tillerpilot/Vanzuki makes the "stepped" washers from 7075 aluminum to stop the movement. He has pics here showing how the springs have moved so far as to rub on the pressure plate bores. K5 & K7 use the same springs and pressure plate but K7 uses the same dished washers as K4. This seems to mean that the post height in the K7 clutch sleeve hub must be recessed by the height of the dish. Are the post ends in your K5 hub flush with the top of the hub? If not, are they higher or lower and by how much? I'd like to get similar measurements for both a K5 and a K7 hub and it appears that you have yours apart right now. I see K5 clutches on ebay that have the dished washers and I'm betting that the spring tension is wrong because of that.

 

[BillV]

K7 (and K4) use a socket head screw instead of the hex head with captive washer in K5. That's so that the head will fit inside the dished washer. Pics suggest that the height of the dish is about the same as the screw diameter, which I think is 6 mm. That's significant relative to the spring's compressed height. So I'm betting that the K7 clutch sleeve hub is different in some way that gives the same compressed height. A 6 mm shorter post is the likely suspect.

 

[BillV]

Here's why I think the dished washer shouldn't be used on K5/K6. I couldn't find a Suzuki clutch cross section but this Honda is reasonably close. The K5 style clutch bolt is on the left and the dished washer style on the right. The dished washer causes the spring to be longer by the depth of the dish, which would result in lower tension.

One way to correct this is to reduce the height of the mounting post by the amount of the depth of the dish. But that would require machining the clutch sleeve hub.

Note that the Honda has a flat washer seat with a concave clutch plate washer as is installed here. The cross section provides a useful perspective. I wish that such a drawing was available for the Suzuki clutch but there were very few such drawings of any clutches.

 

[BillV]

Where did you get that stack height? I can't find any mention of it in the service manual, including other years. Page 3-96 mentions the use of different width outermost driven plates but I don't see any mention of what determines the thickness to be used. Either I'm missing something or the manual needs to be beefed up there.

I've seen 48.18 measured on a K8, 49mm +/- .2mm mentioned, and "Factory specs are 1.885"-1.890" (47.88mm-48.06mm)" for K1-K4. But I can't find any statement by Suzuki.

The clutch mod instructions assume that you have a properly functioning stack and just instruct you on the removal & reinstallation of it. It could also use some beefing up on checking the stack height (or whatever else is appropriate) during reinstallation.

 

[BillV]

As I understand it, you should have two thicknesses for the drive (friction) plates. However of the thinner plates, eight should be one part # and one should be another (all nine with the same thickness). But there should be either one or two thicknesses for the nine driven (steel) plates. I think the Suzuki kit comes with nine 2.3 mm, one 2.0 mm, and one 2.6 mm thick driven plates, of which only nine are used.

 

[BillV]

I see that I wasn't paying attention. Per 10-53 in the service manual, all drive plates are 2.8 ± .08 mm thick. That means that the stack height is 10*2.8 + 9*2.3 = 48.7 mm (1.917 in) when a 2.3 mm ninth driven plate is used. The ±.3 mm ninth driven plate option may be to allow that height to be achieved when the drive plate variations stack up. At least that's the best that I can come up with right now.

I can add that to the K5/K6 service manual if a fairly broad consensus can be reached here. However note that this is for a new clutch. Used drive plates can be much thinner and I don't know what to do about stack height there.

Finally, in partial answer to DutchGSX-R1000's question from five months ago, the OEM spring free length is 57.01 mm and they should be replaced at 54.2 mm. His winding counts seem reasonable when compared to spring pics but I can't be more specific than that. No idea of wire diameter. Coil diameter is also important but it can't vary much, given the constraints of the head.

 

[BillV]

^Look here. There are two versions. So take your pick.

 

[BillV]

They're using it the way it was designed to be used.

 

[BillV]

I was just reading the 2007 New Model Update Seminar Manual and it mentions that the eighteen oiling holes in the side of the clutch hub were enlarged from 2 mm in K5/K6 to 3 mm. This seems like a simple thing to do while the clutch is apart. Has anyone done that or have any opinion pro or con about it?

 

[BillV]

^Search the K5/K6 forum for "clutch chatter". Look for posts that are at least 10 years old. Many of the hits are in this thread. It happens during moderately hard launches.