Topic: 750 Clutch Question

[Mr.Miller]

G'day brains trust, recently started gettign some clutch slip on my K6 cafe bike, in turn ordered a new set of friction & steel plates along with springs.

On removal of the clutch pack I'm a little perplexed, my bike has two double rivited steel plates (see photo) The set I received has none.

Trying to understand if A. I need a double plates in my bike and B. Why there would be two installed.

Appreciate the assist.

[bryanj]

Depends on year and model, was a Honda upgrade to "cure" clutch rattle

[Mr.Miller]

From my understanding this was an introduction of a single twin rivited plate. Not two?!?

[Don R]

 I believe there was one in 76 and up, it appears someone was already in there before you. The double plates are difficult to find these days.

[bryanj]

Its a gold wing part, i have a nos one somewhere.
Ask Hondaman quoting your year and engine number and i am sure he will set you right

[PeWe]

My K6 did not have the clutch with double riveted metal plate.
Clutch fibers as the later. 7 fibers, the outer slanted with wider tabs.

I have bought a used K6 clutch from eBay USA and it was like mine.

Clutch with double metal had a 2-3mm deeper outer steel basket and matching  deeper alu part with grooves for the metal discs. K7-K8 and F2-F3 had those.

Here is the clutch incomplete.

My K6 has got a later clutch so no problem to get it to fit. Old F2 clutch.

Maybe very late K6 got the later clutch setup?

[Mr.Miller]

Thanks for the feedback..

The bike was running and riding fine, just starting to slip in high RPM. I ordered plates as a percaution and this is how I removed the clutch pack from the bike.

[newday777]

Thanks for the feedback..

The bike was running and riding fine, just starting to slip in high RPM. I ordered plates as a percaution and this is how I removed the clutch pack from the bike.

Did it start slipping after you changed your oil? Sounds like someone put in oil with friction modifiers.

[Mr.Miller]

No, just worn out friction plates.

[Floshenbarnical]

Unless yours is FUBAR I'd just reuse it. I rebuilt mine this summer and just used the one that was already in there, but replaced all the other steel and friction discs

[MauiK3]

Is there a manual somewhere that details the clutch parts?

[CycleRanger]

Here's the service bulletin about the clutch plates.
If you need a shop manual you can download a pdf from the link in my sig.

[Don R]

 Thanks for the diagram, I printed it for my reference, it will go in my cb750 Book in case it's not already in there.

[Mr.Miller]

Just so I'm clear as I don't think anyone has seen the point of this thread as yet - My bike has TWO twin steel plates fitted. Trying to understand why.

[bryanj]

Idiotic po

[Mr.Miller]

Idiotic po

?

[CycleRanger]

Idiotic po

?

He means that those plates were likely installed by a previous owner at some point and we will likely never know why.

[Mr.Miller]

Idiotic po

?

He means that those plates were likely installed by a previous owner at some point and we will likely never know why.

Ohh.. Hehe yes, starting to think the same. Before passing judgment I thought it best to ask the group as I know very little.

Cheers,

[PeWe]

CB750 is learning by doing;)
This forum is a great help.
I bought the Haynes manual.
Asked friends.
I took the entire bike apart that way. I remembered how everything sat.

Different with a bike where a PO has done "modifications".

I thought I new most to know after at least 3 engine openings.

This forum has added tons of info that was handy when I restored again.
Bulding another  bike with stray parts.

Use google search:
sohcforums + search expression.

Sohcforums + clutch
CB750 can be added too.

[Mr.Miller]

Just wanted to say thx to all for the assist on this wonderful site. I feel I ask a lot and return very little being I'm a CB new guy.

For the record, if anyone else is reading this in the future. I stripped the entire clutch pack, measured everything against the manual and installed as per the above diagram using a single "twin" steel plate bolted the old bus back together and it's perfect.

Thanks again!

[CycleRanger]

Nice! Thanks for the follow-up. 

[PeWe]

Factory fix on a K6 means that you replaced the outer steel basket pos 1 and Clutch center pos 3 + added the clutch plate B pos 2 instead of one std metal disc. 6 metal as before.
Hopefully fresh clutch fibers too

These are the later used in K7-8, F2-3.  The
The outer basket is 3mm deeper as the clutch center to get room for the thicker clutch package.

****  "Field fix" *****
For stock K6 parts and earlier you remove 1 fiber + 1 steel. Then add the double metal plate B.

I bought a used old complete F2 clutch and noticed what differed compared to my K6.

Clutch cover pos 5, I used my old K6.

Earlier clutch covers have a rounded deeper knob, boss for thread that can hit the later deeper basket.

I'll test the field fix on my rattling K2. Maybe today
Hopefully no slip with one clutch fiber less.

I had to upgrade since +100whp with much more torque needed it. A more rigid clutch.
Stock with glass beaded metals + harder springs ok for +80whp.

The doc below mention the engine serials when the factory fix was introduced.

But, the clutch package height one thing to verify.
Early:  1.460" (37.084mm)
Late: 1.560" (39.624mm)
Numbers from CycleX.

So package can not differ too much. If 6 fiber discs are used, 12 sides that wear. 1mm is not much then.

[Mr.Miller]

  Exactly the process I went through in the end \/ 

Factory fix on a K6 means that you replaced the outer steel basket pos 1 and Clutch center pos 3 + added the clutch plate B pos 2 instead of one std metal disc. 6 metal as before.
Hopefully fresh clutch fibers too

These are the later used in K7-8, F2-3.  The
The outer basket is 3mm deeper as the clutch center to get room for the thicker clutch package.

****  "Field fix" *****
For stock K6 parts and earlier you remove 1 fiber + 1 steel. Then add the double metal plate B.

I bought a used old complete F2 clutch and noticed what differed compared to my K6.

Clutch cover pos 5, I used my old K6.

Earlier clutch covers have a rounded deeper knob, boss for thread that can hit the later deeper basket.

I'll test the field fix on my rattling K2. Maybe today
Hopefully no slip with one clutch fiber less.

I had to upgrade since +100whp with much more torque needed it. A more rigid clutch.
Stock with glass beaded metals + harder springs ok for +80whp.

The doc below mention the engine serials when the factory fix was introduced.

But, the clutch package height one thing to verify.
Early:  1.460" (37.084mm)
Late: 1.560" (39.624mm)
Numbers from CycleX.

So package can not differ too much. If 6 fiber discs are used, 12 sides that wear. 1mm is not much then.

[PeWe]

Adjusted the adjuster screw.  Tighten it by light hand until it stopped, 1/4turn out and locked by nut.
Rattle gone.
This with K2 6 metals and 7 fibers. No double metal disc.

Adjuster screw at Honda max setting 1/2 turn out make a rattling, hammering clutch at idle. Disappear when squeezing the clutch lever.

This screw need to be adjusted after a ride if clutch has been assembled with new oil soaked discs.