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1961 CB72 Project

Want to keep a Restoration Log? Post it here! You can include photos. Suggested format: One Restoration per Thread; then keep adding your updates to the same thread...
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G-Man
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Post by G-Man » Mon May 04, 2015 7:12 am

I was a little bit curious about my later clutch not being a cush drive one. The outer plate and general costruction looked to me like it "ought" to be a cush drive model. I am planning to convert my CYB project to a duplex chain primary drive so I had a need to strip a clutch to replace the sprocket. Curiosity got the better of me.

The rivet heads were all ground off. And then I punched them out.

Image

The outer plate came off to reveal..... a set of 8 cush drive rubbers and mounting posts....

Image

Here is the sprocket with the rubbers in place. Note the cutaway on one side of the rubbers. This makes the drive more resilient in one direction than the other. Very clever engineering on the part of the Honda guys. In theory you could switch them around to change the level of cusioning to the drive. The drive and overrun stiffnesses will be different.

Image

Here are a couple of pics of the clutch basket after an initial clean up. Notice no fancy scalloped fingers on the basket and no spiral oil groove which would 'normally' identify a cush drive clutch.

Image

Image

And here are the component parts. Basket, sprocket, rubbers and outer plate....

Image

A considerable part of the weight of the clutch is the sprocket. The basket is featherlight without it. With an alloy sprocket, my CYB clutch will be a lot lighter.

G
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
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LOUD MOUSE
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Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Post by LOUD MOUSE » Mon May 04, 2015 3:42 pm

Adding pics is more work than typing but I'll show every part of a actual CUSH DRIVE but not with the outer basket taken apart.I'll send pics of the friction disc HONDA used through the years next. .............lm

G-Man wrote:I was a little bit curious about my later clutch not being a cush drive one. The outer plate and general costruction looked to me like it "ought" to be a cush drive model. I am planning to convert my CYB project to a duplex chain primary drive so I had a need to strip a clutch to replace the sprocket. Curiosity got the better of me.
The rivet heads were all ground off. And then I punched them out.
The outer plate came off to reveal..... a set of 8 cush drive rubbers and mounting posts....
Here is the sprocket with the rubbers in place. Note the cutaway on one side of the rubbers. This makes the drive more resilient in one direction than the other. Very clever engineering on the part of the Honda guys. In theory you could switch them around to change the level of cusioning to the drive. The drive and overrun stiffnesses will be different.
Here are a couple of pics of the clutch basket after an initial clean up. Notice no fancy scalloped fingers on the basket and no spiral oil groove which would 'normally' identify a cush drive clutch.
And here are the component parts. Basket, sprocket, rubbers and outer plate....
A considerable part of the weight of the clutch is the sprocket. The basket is featherlight without it. With an alloy sprocket, my CYB clutch will be a lot lighter.

G
Attachments
Look at the middle of the pressure side and you will seee the same raised circle plus 4 holes at 90 degrees to each other. I've had 2 of these with the circle but no holes. (?)
Look at the middle of the pressure side and you will seee the same raised circle plus 4 holes at 90 degrees to each other. I've had 2 of these with the circle but no holes. (?)
IMG_0049a.jpg (204.52 KiB) Viewed 752 times
Look at the middle and you will see a raised circular area and the left will have the deep spline and the right will have the thin splines.
Look at the middle and you will see a raised circular area and the left will have the deep spline and the right will have the thin splines.
IMG_0052a.jpg (219.93 KiB) Viewed 752 times
Look at the fingers and that is the casting of the CUSH DRIVE.
Look at the fingers and that is the casting of the CUSH DRIVE.
IMG_0053a.jpg (166.13 KiB) Viewed 752 times
Look closely and you can see the neoprene disc between the steel plate and sprocket.
Look closely and you can see the neoprene disc between the steel plate and sprocket.
IMG_0054a.jpg (168.16 KiB) Viewed 752 times
Look closely and you can see the spiral oil groove. The first ones didn't have the groove. (?)
Look closely and you can see the spiral oil groove. The first ones didn't have the groove. (?)
IMG_0056.JPG (76.85 KiB) Viewed 752 times
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LOUD MOUSE
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Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Post by LOUD MOUSE » Mon May 04, 2015 4:50 pm

HONDA used several friction disc over the years and you will see how the changes came along.
The last ones they superseded to makes no since after they had used the 020 issue which worked better than all the previous changes.. .................lm
LOUD MOUSE wrote:Adding pics is more work than typing but I'll show every part of a actual CUSH DRIVE but not with the outer basket taken apart.I'll send pics of the friction disc HONDA used through the years next. .............lm

G-Man wrote:I was a little bit curious about my later clutch not being a cush drive one. The outer plate and general costruction looked to me like it "ought" to be a cush drive model. I am planning to convert my CYB project to a duplex chain primary drive so I had a need to strip a clutch to replace the sprocket. Curiosity got the better of me.
The rivet heads were all ground off. And then I punched them out.
The outer plate came off to reveal..... a set of 8 cush drive rubbers and mounting posts....
Here is the sprocket with the rubbers in place. Note the cutaway on one side of the rubbers. This makes the drive more resilient in one direction than the other. Very clever engineering on the part of the Honda guys. In theory you could switch them around to change the level of cusioning to the drive. The drive and overrun stiffnesses will be different.
Here are a couple of pics of the clutch basket after an initial clean up. Notice no fancy scalloped fingers on the basket and no spiral oil groove which would 'normally' identify a cush drive clutch.
And here are the component parts. Basket, sprocket, rubbers and outer plate....
A considerable part of the weight of the clutch is the sprocket. The basket is featherlight without it. With an alloy sprocket, my CYB clutch will be a lot lighter.

G
Attachments
HONDA issued both of these as 22201-268-.020. The first issue has 1/2" wide by 7/8" long the other is 1/2" wide by 1/2' long. Both have aluminum cores, black neoprene/cork and the second has a thinner core bya couple of THO.
HONDA issued both of these as 22201-268-.020. The first issue has 1/2" wide by 7/8" long the other is 1/2" wide by 1/2' long. Both have aluminum cores, black neoprene/cork and the second has a thinner core bya couple of THO.
IMG_0057.JPG (237.04 KiB) Viewed 736 times
This is the last issue HONDA superseded to and is the same material as 020 but 7/16" wide and 7/16" long pads.Takes 6 of them and 6 steel disc. 22201-MK2-000.
This is the last issue HONDA superseded to and is the same material as 020 but 7/16" wide and 7/16" long pads.Takes 6 of them and 6 steel disc. 22201-MK2-000.
IMG_0058.JPG (220.22 KiB) Viewed 736 times
Here are the first issues which are sort of PHENOLIC/CORK.You can see that the pads are not wide or long so if we powered up and let out the lever you would burn them and they would slip. 22201-259-000 and 22201-268-000 would be the part numbers.<br />I don't
Here are the first issues which are sort of PHENOLIC/CORK.You can see that the pads are not wide or long so if we powered up and let out the lever you would burn them and they would slip. 22201-259-000 and 22201-268-000 would be the part numbers.
I don't
IMG_0059.JPG (175.14 KiB) Viewed 736 times
Here you see those last ones from the outside and the thin one is for the 5 disc and the thicker is for the 4 disc.HONDA had a 6 disc clutch and it had 3 wires at the center hub. The very first clutch for the C72/77 didn't have any wires. Then 2-3-2 to th
Here you see those last ones from the outside and the thin one is for the 5 disc and the thicker is for the 4 disc.HONDA had a 6 disc clutch and it had 3 wires at the center hub. The very first clutch for the C72/77 didn't have any wires. Then 2-3-2 to th
IMG_0062.JPG (207.62 KiB) Viewed 736 times
Here is the CUSH drive steel plate on a 020 FD. The contact area is 100 percent. See the anti warp slots!
Here is the CUSH drive steel plate on a 020 FD. The contact area is 100 percent. See the anti warp slots!
IMG_0060.JPG (214.98 KiB) Viewed 736 times
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G-Man
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Post by G-Man » Tue May 05, 2015 12:45 am

LM
Many thanks for all your efforts there. Very informative. I have one clutch with all those later parts, and have now found a selection of plates, which I'll compare with with your photos.

G
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
Top
LOUD MOUSE
honda305.com Member
Posts: 7817
Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Post by LOUD MOUSE » Tue May 05, 2015 4:58 am

Hope I have helped you and others to know the CUSH DRIVE CLUTCH. ...................lm
G-Man wrote:LM
Many thanks for all your efforts there. Very informative. I have one clutch with all those later parts, and have now found a selection of plates, which I'll compare with with your photos.

G
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User avatar
G-Man
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Posts: 5678
Joined: Wed Mar 25, 2009 5:17 pm
Location: Derby, UK
Contact:
Contact G-Man

Post by G-Man » Tue May 05, 2015 5:58 am

Yes, my main aim was to use a clutch drum with some resilience rather than the solid sprocket mounting of the '61 type clutch.

My duplex chain kit for the CYB project will fit all of those clutch baskets with a resilient mounted chainwheel, so I am happy.

G
LOUD MOUSE wrote:Hope I have helped you and others to know the CUSH DRIVE CLUTCH. ...................lm
G-Man wrote:LM
Many thanks for all your efforts there. Very informative. I have one clutch with all those later parts, and have now found a selection of plates, which I'll compare with with your photos.

G
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
Top
User avatar
G-Man
honda305.com Member
Posts: 5678
Joined: Wed Mar 25, 2009 5:17 pm
Location: Derby, UK
Contact:
Contact G-Man

Post by G-Man » Tue May 05, 2015 6:10 am

Yes, my main aim was to use a clutch drum with some resilience rather than the solid sprocket mounting of the '61 type clutch.

Sprocket riveted directly to clutch drum.....

Image

Later sprocket drives by resilient rubber spacers ....

Image

My duplex chain kit for the CYB project will fit all of those clutch baskets with a resilient mounted chainwheel, so I am happy.

G
LOUD MOUSE wrote:Hope I have helped you and others to know the CUSH DRIVE CLUTCH. ...................lm
G-Man wrote:LM
Many thanks for all your efforts there. Very informative. I have one clutch with all those later parts, and have now found a selection of plates, which I'll compare with with your photos.

G
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
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