Topic: Adding extra disc/plate to clutch... anyone done this? Does it help?

[Jerry E.]

I have an 1975 FO CB750 motor that I bought a clutch disc pack for (has an extra friction plate, 8 instead of 7) included. I've read on this forum that an extra plate helps the clutch performance. Anyone have any firsthand experience doing this? All you do is add an extra friction and steel disc, from what I understand. Doing that fills the clutch basket completely full of disc's. Opinion's? I noticed there is nothing about doing this upgrade in Hondaman's book, but I read it in an old article archived on this forum.

[Jerry Rxman Griffin aka MuthaF'er]

Or do the early 'field upgrade' that Honda came out with. It involves adding a double plate from a Gold Wing in the center. In 77 they came out factory with the fix

This is the later 77/78 (slightly longer) basket but it incorporates the double plate this 'fix' refers to



.

Can't readily find my Honda bulletin that tells of this but it is posted up somewhere

[brewsky]

I would be careful not to mix/match plates, baskets, and pushrods between the early and late versions.

I made that mistake and had a time getting it sorted.

[Dream750]

Or do the early 'field upgrade' that Honda came out with. It involves adding a double plate from a Gold Wing in the center. In 77 they came out factory with the fix.

Is this the Honda “field fix” and “factory fix” bulletin you’re thinking of?

(click on images for a large view)

[voxonda]

I use the extra plate clutch kit from APE in the (F2) block we use for race/endurance demo's. Works flawlessly!

[RSchaefer]

Relative to Hondaman's book - man I'm thinking I must have read it 100 times now.  I do specifically remember Mark discussing this issue in the book, sorry I do not have it with me at the moment to reference page number.

1st let me say Marks book is invaluable and worth every penny, however there are three issues I have had with Marks book, not necessarily bad issues:

1. there is a huge amount of information to digest, even in one sentence.
2. Mark has a unique way of telling the story, probably the engineer in him, but I am an engineer also and its sometimes difficult for me to rap my head around what he just said.
3. there is allot of detail buried in the descriptions under the pictures.  In other words you read the text and really need the description under the picture to fully understand what he just said, or there is critical detail in the description that is not included in the text.

So the long and the short of it, I believe I read the specifics of that extra plate in Marks book and I too am restoring a '75, F0

[Jerry Rxman Griffin aka MuthaF'er]

That's the one Dream.

And what Bewsky says is true. I have found it out too. It's not that I wouldn't do it, just pay attention to detail and do your research if you go this route. You'll notice there are a few different part numbers between clutches of the early and late bikes. I just received my new Honda discs and need to head out to my cold garage and get mine finished. First attempt was not good. I did install the newer basket but probably mixed and unmatched as he mentions.

Other than 1) the 8 disc kit, 2) the field fix, or 3) totally replacing the entire clutch assembly including the cover you may have to live with the inherent rattle.