Setting up a diaphragm spring clutch

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Setting up a diaphragm spring clutch


Post by 2dogs » Wed Dec 28, 2005 3:14 pm

Description: How does one set this diaphragm spring clutch up?

Post by 2dogs on Jul 2, 2004, 12:12am

I just bought one of these "Sifton" diaphragm spring clutches from V-Twin with the 5 stud clutch hub to replace the well-worn 10 spring setup. I am using 4 steel drive disks, 5 friction disks and a mouse trap clutch booster.
How does one set this diaphragm spring clutch up? With the old style springs it starts with a simple measurement of distance between the pressure plate and the retainer ring.
I got zero instructions with this kit. Is is really so simple that no instructions are required? Has anyone set one of these up and care to share the information?


Post by 2dogs on Jul 5, 2004, 12:32am

I can't believe no one has a word to offer on adjusting this modern style clutch in a Pan. I cannot be the first one here to have tried one on. I'll leave the post another day or so and then delete the damn thing.

dos perros

Post by Billy on Jul 5, 2004, 1:19am

2 dogs, This is also a Holiday weekend. Chill dude.

Late style Big/T. was indeed a diaphram pressure plate till 1997. & was retained by a large Snap ring. Only adjusting on this one was the push-rod free-play.
1998+ later was changed to a 6 bolt diaphram pressure plate. But you tightened these down till they bottemed & that was set. & you still could adjust the push-rod play.

So although you have a diaphram set-up & a 5 stud hub. I'm not sure these are set exactly the same.
So rather than me guess, & hope you get a correct answer at your expense. I haven't replied because of this. Also, If I saw it, I could adjust it. Simple as that..
It sounds like the '98+ later set-up. If so it is so simple you wouldn't need directions. Just tighten down all 5 nuts till they bottom out & adjust the push-rod to 1/8- 1/4 free-play & lock down.
But because:
(1) I haven't seen this set-up you have, I'm guessing.
(2) I prefer the old-style 5 stud/springs.

This board has several hundred members at least, surely some one has done this set-up.
I have NOT.
Sifton's name is V Twin's label. = crap. They bought it when Sifton went bankrupt. So the name Sifton no longer means what it used to mean.

Post by 2dogs on Jul 5, 2004, 11:20pm

Billy: You're right, I should have had a Guinness instead of ranting about not getting any replies.

I noticed too late that "45partsdepot" also sells diaphragm spring clutch kits. I bought this one through the parts counter at local HD shop. I also discovered too late that Sifton went TUITD and V-Twin took over. I've not been real happy about any of the stuff ordered through V-Twin since I started this project but they seem to be the only ones with the parts I need (crap that they are).
I originally went down to order a replacement pressure plate, 10 springs and retainer ring but my "friend" at the parts counter advised that this "Sifton" setup was a better way to go.
This whole project, my first basket, has been completed in small trial and error steps, mostly error. If this diaphragm setup isn't right for my '63 I'll keep the 5 finger hub and retainer ring that came with it, order a new pressure plate and springs and put the diaphragm parts on eBay.
Thanks for your comments, Billy! Much appreciated.

Post by Billy on Jul 5, 2004, 11:56pm

2dogs, It's cool.
The set-up is supposed to be a good one...

It's a shot anyhow............
As far as a parts source for Pans, I think Kurt may be starting to sell big twin stuff ? So he may only have this set-up for the 45 Flatty's, But he "might" know how to set it.
Also for the U.S. & for the European market

The only parts you will get from the HD Stealerships are
With NosParts/jwboon you can get either NOS[Real Deal] or quality aftermarket. "Your choice" ;D

Post by Mbskeam on Jul 6, 2004, 5:43am

hello,I just looked in my 99 roadglides service manuel and the ill. shows that the bolts just go in and tighten down. I think you have a diff set up. I just looked at my rivera catalog in there clutch sect. it has a pressure plate then diaphram the nut/bolts then you thighten so that the dia. is flat to within.010 of being flat. If this is not what you have please describe the parts you have, I have been wondering about this set up my self, hope this helps

Post by 2dogs on Jul 9, 2004, 3:36am

Billy: Not comfortable asking help from Kurt at 45partsdepot when I did not buy the product from him.

Mbskeam: The parts consist of an thick aluminum retainer ring with 10 holes, a dome shaped diaphragm clutch spring and an aluminum pressure plate. All parts assemble over a 5 stud clutch hub included in the kit. It's V-Twin part # 18-0540 if you have a catalog handy. I'll take a digital pix tomorrow and post here if I can (not sure if posting images is allowed.)
Another problem with this set up is going to be getting the diaphragm spring ring and retainer centered over the clutch plates. Both parts have a certain amount of side to side slop and could easily be tightened down off-center, if that makes any sense at all. Maybe pictures will be some help if I can post.

Post by Billy on Jul 9, 2004, 5:58am

2dogs, I understand..Besides if Kurt knew, I think he might have posted adjutsment procedure, by now.
I think pics would be Exactly what is needed here. As far as posting being allowed. It is my impression from Panhead, it IS encouraged!! Please post pics..
Curious to see this set-up already.

Post by Kurt on Jul 9, 2004, 1:02pm

Actually guys, I missed this entire post.
No problem on helping someone out, that's also part of what I do.
I adjust it as follows, it may take minor adjusting later, but it normally works.

Loosen the clutch adjusting screw completely, install the assembly with lock tabs and run the nuts down until you have 2 to 3 threads showing. I then take a depth mic, or a slide caliper and measure the distance from the outer aluminum plate thru to the hub. I take the measurements next to the nuts. At this time I try to get the measurements within a couple thousands at the 3 points. Actuate the clutch a couple times and re-measure. Make adjustment as necessary, then bend the lock tabs. Now adjust the clutch so there is a little play. The Diaphragm is real sensitive to adjustment, it takes very little pressure to release the clutch pack, but it has excellent holding pressure. If it's adjusted too tight, you'll burn up your clutches.

That should be good for the installation.


Post by 2dogs on Jul 10, 2004, 5:42am

I've got a couple of pictures of the clutch kit but can't find a way to post them here.

Post by Panhead on Jul 12, 2004, 8:21am

Here are the pics:


Post by 2dogs on Jul 16, 2004, 6:01am

Panhead: Thanks for posting the pictures for me. And thanks to Billy, mbskeam and Kurt for advice offered. I'm sure I'll get it set one way or the other or maybe a combination of all.
Even so, I can't say too much good about the V-Twin kit. It looks OK but I still think they owed me some basic directions including a simple way to center the spring and the outer retainer ring.
Thanks again to everyone.


Post by Billy on Jul 16, 2004, 6:48am

2 dogs, I have to eat my words, Cause I never saw anything like that. It's the silver dished peice I mean.. ???

Post by 2dogs on Jul 17, 2004, 4:36am

Billy: Pretty far out, eh? Just my luck to get something so out of the mainstream that no one's ever seen it much less tried one before.

Post by Billy on Jul 17, 2004, 6:23am

2 dogs, Yeah that 3rd piece, the silver dish that throws me off. I can see & understand the top plate & the pressure plate, But the 3rd part [dish]looks like it doesn't belong. But, I don't know.
Call up where you got it, or V-twin & ask for some paperwork. I have received wrongly packaged & labeled parts. As I'm sure many here have..
So Who knows.. ???
Sorry Dude!!!

Post by 2dogs on Sept 18, 2004, 6:07am

I finally got around to calling V-Twin about this kit. The first woman I spoke to said they couldn't help me and referred me to Zoom Cycle. I called Zoom twice. The first time earned a zero. The second time someone there said they would try and help me and left it at that. Heard nothing from them since. Called V-Twin again last week and found "Ceil" who actually tried to help. Said she would contact their tech and see if there was supposed to be some kind of "adjuster kit" included that was missing from my box. She also acknowledged that there was supposed to be a 1 page instruction sheet included which I also did not get. Nothing has turned up yet.

As of now I've given up on the whole diaphragm spring kit and returned to a standard 10 spring clutch.

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Post by panhead » Fri Jul 21, 2006 9:36 pm

the larger plate goes's the release plate. The flat side goes toward the plates. The diaphram spring goes inside that with the spring angle facing outboard. The smaller billet alum piece has a notch around the diameter towards that sits on the fingers of the diaphram. Tighten the diaphram to within .001 inch flat. Use a straight edge at the bolt holes and measure with a feeler guage along the outside edge of the diaphram spring to check for the .001 flatness. Then adjust your clutch throwout and cable as instructed in your manual.


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diaphram clutch


Post by Panacea » Wed Jan 24, 2007 4:12 am

Can anyone do a product review on the diaphram clutch? I am considering buying one. thanks..Mike

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Post by panhead » Thu Jan 25, 2007 9:25 pm

I tried one from which worked fine, only problem was it was too broad (the cover didn't fit). Maybe there is a better fitting one now available.

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Diaphram clutch


Post by Panacea » Thu Jan 25, 2007 10:37 pm

For 165.00 the parts should fit perfect. I'll just get a new pressure plate and spring collar, Just thought if this was a big improvement i'd go for it...Mike

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Post by panhead » Thu Jan 25, 2007 11:50 pm

The price is 92.50, it's easy to setup and less noisy. I have not experimented too long with it but installes in on my 45".

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Post by Panacea » Fri Jan 26, 2007 3:26 am

That's reasonable, 45 parts depot must be cheaper than custom chrome, or it may be a different unit all together. Thanks for the info! Mike

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