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Discussion Starter #1
So just bought my bike and took it for a good ride on the weekend...love it.But now and then the bike on the release of the clutch will launch and engage instantly or this is how it feels.
Now if i was turning or u turning this could be bad....

So my questions are

1. ive heard SP1 has a dodgy clutch when hot..is this true?
2. if so is there any way to rectify
3.are slipper clutches available? do you need any mods to fit?

Cheers
:):):confused::)
 

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Yes, the RC51 does have a bit of a dodgey clutch grab, but i've never had it launch on me. its a weird clutch and it can be a little difficult when you first own the bike, especially if its your first v twin.
that being said there ae slipper clutches out there, yoyodyne makes one and i believe there are others.
 

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Glad this came up again. My SP1 still does exactly the same thing. I went completely thru the clutch master and slave and replaced all the necessary components. My recent thread about that was 'Launching Clutch'.
But it still does that once in a while. Yeah, it's a little nerve racking when it happens to you in the left turn lane!
It always makes a loud noise, like a beer belch as it tries to instantly engage. Happens to me about once every couple hundred miles or so. Twice since I rebuilt my cylinders.
 

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You could try retrofitting your clutch with the SP2's judder spring/seat and inner plate friction plate.
The purpose behind those parts was to try and make the clutch engagement less grabby.
 

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Discussion Starter #5
Is it a hard job to retro fit the sp2 clutch?

Also any where i can down load a service /workshop manual/
 

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How many miles do you have on the 'ol girl?? Maybe a fresh clutch/springs may not hurt...

Just another item that makes this bike just alittle different.
 

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Im at 35 000 Km's
I normally don't touch a clutch unless its slipping or not enegaging properly. That being said if you don't like the action, change it. May give the SP2 retro a try or just blow the cash and get a slipper.
 

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So it looks like all we need is:
a) the sp2 friction plates (assuming the steel plates are ok),
b) the judder spring
c) and the judder seat


I know I'm repeating what SubSailor said, just wanna make sure I got this right. And it all fits in the sp1 clutch center and clutch outer?
I'm also assuming the steel plates are the same thickness for both SP's

After some hunting around, it seems that most people prefer to stay with the oem plates for general street use. Does this sound right?
 

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You may as well change the steel plates too while you're in that deep...;)

The Barnett kit for around $150 includes new steel plates.
 

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You may as well change the steel plates too while you're in that deep...;)

The Barnett kit for around $150 includes new steel plates.

I kinda figured, but was gonna look for the typical signs, blueing or checking on the surface, and the manual has the specs/service limits for them.
Is Barnett a little more grabby than oem? Well behaved when hot or cold?
 

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Most anything I have rebuilt, driven after a clutch change does have more "grab"....of course you are talking to the number one procrastinator in doing this deed.:D
 

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The more I think about my clutch, and how it acts other than the occasional beer-belch quick-launch, I've also notice that it acts a little diferently accross the temperature range. Some times it's real grabby as I'm upshifting, sometimes it shifts like a dream. Never really been able to notice it slipping yet, but haven't really hammered down at all since clutch master and slave rebuild. Well, ok, i'm lying. I have. :D But I attributed that to the explaination SubSailor gave about honda using judder spring and seat to remedy that.

Next weekend I'll take the clutch apart for inspection and see what I see...
Thanks for overlooking a thread jacker: me :eek:
 

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Nah...its legit to me...clutch issues are okay to brainstorm. Beside some of what is discussed may or may not help Ozzy...but its here.

I am still curious about the belching deal you speak of???

The only difference I experience is oil life...fresh oil the gear box is a dream. A few times out on the back roads....it gets "loose" in there. Thats why for the longest I have ran 20 W 5o and changed my oil between 1500-2000 mile intervals. Expensive and OCD but well worth the performance for me.
 

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So it looks like all we need is:
a) the sp2 friction plates (assuming the steel plates are ok),
b) the judder spring
c) and the judder seat


I know I'm repeating what SubSailor said, just wanna make sure I got this right. And it all fits in the sp1 clutch center and clutch outer?
I'm also assuming the steel plates are the same thickness for both SP's

After some hunting around, it seems that most people prefer to stay with the oem plates for general street use. Does this sound right?
To change your SP1 clutch plates to SP2 clutch plates, you'll need:

Qty 5, Clutch drive (friction plates), pn 22201-MAT-E00
Qty 1, Disk-A (outer friction plate), pn 22201-MAT-000
Qty 1, Disk-B (inner friction plate), pn 22202-MAT-000
Qty 1, Judder Spring, pn 22402-MAT-000
Qty 1, Judder Spring Seat, pn 22125-MAT-000

Disks A and B are identified by one tab colored green on the outer edge, and have dark speckles on the friction material.
Disk-B is the inner friction plate that has larger I.D. to clear the judder spring.
Disk-A is the outermost friction plate, and has its tabs installed on the shallow slots of the clutch basket.

The 6 steel drive plates are all the same on SP1 and SP2.

On an SP1, to replace friction disks, just order Qty 7, pn 22201-MAT-E00
 

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...Qty 1, Disk-B (inner friction plate), pn 22202-MAT-000

...Disk-B is the inner friction plate that has larger I.D. to clear the judder spring.
I caught that in the oem diagrams. Only SP2 listed disc-b as part of the friction plates required.

Thanks for all the info, it's spot on and very clear. :)

I have most tools a guy needs, but haven't done a bike clutch before. Anything special I need for this?
 

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Nothing special. Just metric socket set.
The clutch cover uses an 0-ring type seal, and most of the time you can reuse it as I did.
The clutch pressure plate has 6 bolts that hold the springs, and you loosen and tighten them a little at a time in a cross pattern. These are long bolts and will take a while to fully loosen or tighten.
I pull the pressure plate and drive/friction plates and lay them in a row to reinstall them in the order they came out.
The judder spring seat goes in first and the judder spring goes in with the narrow/taper end towards the seat.
Be sure and pre-soak the new friction plates in motor oil for a while before installation.
The outer friction plate had its tabs offset and laying in the shallow slots of the clutch basket.
Properly tighten and don't over-tighten the clutch spring bolts. You don't want to strip the threads in the basket.
Same for the clutch cover bolts.

As always, refer to the service manual, which BTW, has a typo listing plate-A and plate-B opposite from the parts manual.
 
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