Question for the Clutch experts

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KosRider

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Got a question for you Vmax clutch experts out there. For a winter project, planning to inspect / possibly upgrade the stock clutch on my 06 Vmax that has ~9500 miles on it. No issues of serious slippage? yet.

From the many threads / posts from the past few years, it seem the preferred clutch upgrade route many have done is the ?double D? approach where you : 1) remove and discard the retaining wire / clutch damper plate, 2) replace the stock half friction disk with a full disk, 3) rough up the steel disks prior to reassembly, and 4) add a second stock diaphragm spring on top of the existing one. With the Double D upgrade, the pros - you end up with a clutch that grabs and holds on BIG TIME to the power the Vmax engine puts out ; but the flip side is that you now need to be aware that the clutch is no longer the weak link in power transfer to the wheel. The cons ? a significant increase in clutch lever pull. Using the PCW spring get?s you somewhere between the pros & cons of the Double D approach.

From a Google search, found some early V-max clutch upgrade information out there in cyber space, (site called ?the-clearing.org? from the early 90?s ?) where they were doing the two types of ?double D? mods on the Vmax: the complete ? as mentioned above, or a partial, (partial being just an extra spring). Don?t hear anything about doing the partial Double D now a days; maybe slippage issues remained ? :ummm:
Someone also noted that back then, that ?You can improve the (clutch) hit substantially without increasing the required pull by removing the rearmost 1/2 clutch plate and replacing it with a full plate.?


So my question to you Vmax clutch experts out there ? has anyone ever tried / tested this approach of replacing only the half friction disk with a full one / roughed up steel disks / NO second diaphragm spring / and either keeping or most likely - completely pulling the clutch damper guts ?? I wouldn?t expect this to be close to the Double D in grab strength w/o the second spring, but a significant improvement over the stock clutch w/o the increase in lever pull maybe ??? :hmmm:
Just thinking it might be interesting to test if no one?s done it; but chances are it?s been tried by someone. Can always go back in and add the second spring if needed; that?s why I ordered two gaskets from you Sean ! Couldn?t find where this question / topic had been discussed in the VMF archives, so thought I?d float it out there for comments from the forum experts. Curious if there?s any advantage to try this approach? or forget it cuz it went the way of the ?partial DD?.
 
I went with the Barnett clutch & pressure plate and the pull was to much ( have rheumatoid arthritis ) so I found a 2003 FJR1300 clutch master for the easier pull and that works great. From what I have gathered the stock friction plates do a better job on the clutch control ( easier to slip the clutch when launching the bike ). I dont even try to launch the bike so I am happy with my set up.
 
Yes, you can install just the spring and leave the rest. Quicker install and works almost as well. The inner dampener assembly can be swapped out too but I would not expect much of a gain in holding power. Just a slightly harder hit between shifts.

Sean
 
Yes, you can remove the half plate, clutch boss spring, spring seat, and the retaining wire and install one full size friction plate in place of those parts and leave it at that.

That will give you a bit of an increase in holding power, not as much as the DD, but it will not effect lever effort just as you had asked.

The "hit" will increase also since you are removing the clutch boss spring.

If you want more holding power just add the additional diaphragm spring as you noted.

When you clean the steels you don't want to really rough them up. You need to make sure they are not glazed. Don't be surprised to see some black streaks onon them. Be sure to remove glazing and clean off deposits. As long as they were not overheated (blue) and within thickness, they should be fine.

Don't forget to soak the new friction in oil prior to install and also to make sure all the steels go back in the basket the same way. The steels are like a washer. One side has a sharp edge, one side is a bit more rounded.
 
Thanks for the comments ... very helpful.
+1 Mike on the reminders - thinking of bead blasting the steel and definately soaking the new friction disk in oil prior to install.

Mike / Sean - what do you mean exactly by " Just a slightly harder hit between shifts" expected when removing the clutch boss spring?

Do you mean that when the clutch is engaged it's not as smooth / grabs faster with the clutch boss removed ? Not quite understanding what you mean by this... I better go grab another cup of coffee !

Thanks
 
Yes, kind of like a shift kit. the stock setup is designed to slip a little when shifting to smooth up the engagement.

Sean
 
Now I have some questions.
What is the clutch boss spring?
If I remove the 1/2 plate and replace it with a full one, do I need to do anything else?
Why is the wire thing there?
Why is there spring seat or something which goes in the basket first?

I might have to pull mine apart again. Not that it matters, because I can't get it back on the road yet anyway. grumble grumble
 
Now I have some questions.
What is the clutch boss spring?
If I remove the 1/2 plate and replace it with a full one, do I need to do anything else?
Why is the wire thing there?
Why is there spring seat or something which goes in the basket first?

I might have to pull mine apart again. Not that it matters, because I can't get it back on the road yet anyway. grumble grumble

If you want to remove the half plate and install a full one you need to remove the clutch boss spring, spring seat, and retaining wire.

The clutch boss spring is more or less a cushion for the clutch. It eases the "hit". I think the easiest way to describe the purpose of the spring seat would be a thrust washer or load bearing surface for the spring.

I do not understand the purpose of the retaining wire
 
KOSrider damon set me up with my clutch and he said i could just change out my clutch fibers without pulling apart the most inner half disc set up. that being said i cooked my clutch and i dident trust that the inner parts are still good. damon said its ok because the clutch go's bad in the middle. And he was right. He also said if he was doing my clutch he would do the pcw spring. But he also gave me a deal on a used stock spring that couldent pass up. And a great deal on new fibers and new gaskets and swaped my steels for beedblasted steels. I have a full double D clutch set up now and when i first pulled the clutch lever in i could tell that it is stiffer but not that bad. When i took it for a ride I thought to myself that might be a little stiff in heavy traffic. On the ride i also felt the clutch engauge a kind of short quick spot as i let it out. But not bad at all. easy to deal with. I also could feel it engauge vary crisp when i took it easy going through the gears. But the place I felt it hit hard was when i ran through the gears hard. Im telling you it was night and day over stock. At this point i thought about what damon said about the pcw spring and said to myself better order a pcw spring as soon as i can. That being said I havent got to my pcw set up yet but i did put my UFO exhaust on and took it for a 14 mile ride around town and when i was talking with leesafer on the phone about how great my UFO exhaust ride went he asked me how the clutch worked out. I thought to myself and said you know i dident even notice the clutch. So in that little of time i have adjusted to how stiff it is. not bad at all. Its only another $50 and i will have the double d and the pcw set up so i will buy the pcw spring. also damon told me to use a thin layer of greese on both sides of my clutch housing gasket so i could pull it apart and change to the pcw if i dident like the double D. He also said dont use synethic oil. So at this point I feel the double d is a great set up but i feel it hits a little hard when shifting hard. The stiffer clutch is no biggy at all. But i do understand if someone has joints that cant take it might not be for them. If you remove the most inner clutch half disc and other parts your clutch will have a feel of a shorter throw. Because it wont slip in and engauge. It just engauges in. I was always told you have to give to get..............Mike
 
Thanks for the comments Mike. I was going to shoot Damon for this thoughts on this clutch topic .... but looks like you already got them. :clapping:
I also picked up a used diaphram spring to try the DD with. Hopefully it's a little weaker than a new one would be. Just waiting for my replacement parts from Sean to arrive to dive into this project.

I think I'm going to try / test something a little different. I know how the stock clutch feels / behaves. I'm going in to inspect the friction disks and clean up the steel ones (if needed). If everything looks good, I'm going to reassemble - keeping the half disk & clutch boss assembly in, but add the used diaphram spring on top of the original to have a partial DD type set-up. Want to see if I can keep the smooth engagement when shifting, but have a tighter grip during the rest of the RPM range. I can also guage the increase in lever pressure needed with the second spring added. Hey, if I don't like it / it doesn't work, I can always go back in and add the full friction plate / toss the clutch boss / order & install the PCW spring to try. I'll update this thread / post on what I find.

Been using the std YamaLube 20-50W since new. I don't believe this is considered "synthetic oil" (please correct me if I'm wrong here). Current Clutch seems to like it !!
 
I told damon and jon from ufo that i use 20w-50 yamalube and they said its good stuff if you dont mind spending the money. I put valvoline 10w40 4 stroke oil in for the winter. I new i would be running it alot over the winter so i felt that 10w40 would be better in the cold weather. $5.00 per qt. I went for a ride today and the clutch is a little stiff but i do like the solid engaugment. Like i said the only thing i dont like about the dd is when you race it hard the engaugment is a vary strong hit and it feels to strong. Other than that i like the dd alot. On my ride today i was runing it hard but not all out racing it and the dd was alot of fun. I could down shift into 6000rpm range and ride the clutch with the rpms up and it pulled alot harder than stock. also dont pull your 1/2 disc and clutch boss assembly. Leave the wire alone or you will have hell to pay trying to put it back together. Just inspect up to that point. Take your time and have fun its not hard at all. Just make sure you keep track of how everything come's a part and keep track off it all going back togather...........Mike
 
I just left the machine shop and have approved to have 10 more Gen 1 and 10 more Gen 2 DD clutch spring retainers made .
FYI

rick rash
 
I took out the 1/2 plate on mine and it's got a Barnett in it.
I like it. Not much harder to pull, nicer feel. Works better basically.
What surprises me is that sometimes when I power shift I get little chirps from the tyre.
Not wheelspin or anything like that, just a tiny little chirp. It says "Chirp, chirp. that was sloppy Baz." :biglaugh:
 
If you want to remove the half plate and install a full one you need to remove the clutch boss spring, spring seat, and retaining wire.

The clutch boss spring is more or less a cushion for the clutch. It eases the "hit". I think the easiest way to describe the purpose of the spring seat would be a thrust washer or load bearing surface for the spring.

I do not understand the purpose of the retaining wire
So the clutch boss spring/spring seat are behind the retaining wire? I guess called 'spring cushion' and 'plate seat' by yamaha. So basically it is just bare basket on the new full width disk? The cushion spring I've seen around on youtube not much about the plate seat.
 
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