1961 CB72 Project

[SMBH]

I wished I was as handy as you GMan if I was then I would have used what you are but im not so this is what I went with not standard I know but this is what I used with a DID 219T chain and a slit link after over one thousand miles and no problems.
Expensive maybe but when one loves something, and just how much would it cost for me to get someone to make it.

http://www.ebay.co.uk/itm/Honda-CB72-CB ... SwuMFUZ~eW

[LOUD MOUSE]

Actually a limited number of CL72 bikes did have the left side adjuster.
Who's to know how many as the 1966 parts book shows the 010 issue. . ..............lm

LM

Thanks for clearing that up. I was wondering if the early CLs had the left-hand type but you have explained why they didn't. I know that two of those early ones came from 1961 CB72 engines so the other two could be from early Dreams.

I wonder if Honda just wanted more cooling fins around the cam chain tunnel with those late ones and therefore had to make the tensioner narrower?

G

Of the 4 first issue you will see the 2 on the right are the earliest (sharp edge between bolt holes) and the 2 left have more rounded edges.
The ones with the set bolt on the right came about when the CL72 bikes came with the high pipes.
The pipes were in the way of the adjuster bolt.
I have had tensioners with 3 different wheel diameters but don't know what's up with that as the C/CB/CL engines were the only engines using this design and they all worked.
As you stated the cast cylinder assemblies came with a more narrow tensioner and I haven't figured out what's up with that either.
As you said the wheel could be damaged with a loose adjustment and also by us "pushing on the shaft and causing excessive pressure at the wheel and chain " which caused the wheel to become a sort of sprocket. ...............lm

I tipped out my box of old tensioners and was a little surprised with how many there were.



And when they were in daylight - I could see that I had four early ones. The elusive one from the '61 engine is on the left.




That's the one most in need of attention.

G

[G-Man]

SMBH

I did look at those and the engineering is superb. If I can get a sprocket blank I might have a go and making one... :-)

G

I wished I was as handy as you GMan if I was then I would have used what you are but im not so this is what I went with not standard I know but this is what I used with a DID 219T chain and a slit link after over one thousand miles and no problems.
Expensive maybe but when one loves something, and just how much would it cost for me to get someone to make it.

http://www.ebay.co.uk/itm/Honda-CB72-CB ... SwuMFUZ~eW

[G-Man]

Hah! Just when you think you understand what's going on... :-) That must have been a little awkward adjusting the cam chain on those CLs.

I've just found a needle roller bearing which would take the place of the bronze bush in the primary tensioner. 9/16 x 13/16 x 5/8"

Still around $6

So yes, it is possible to re-purpose a primary tensioner wheel as a cam chain tensioner wheel. Budget about $10 and an ½ hour to do the mods.

G

Actually a limited number of CL72 bikes did have the left side adjuster.
Who's to know how many as the 1966 parts book shows the 010 issue. . ..............lm

LM

Thanks for clearing that up. I was wondering if the early CLs had the left-hand type but you have explained why they didn't. I know that two of those early ones came from 1961 CB72 engines so the other two could be from early Dreams.

I wonder if Honda just wanted more cooling fins around the cam chain tunnel with those late ones and therefore had to make the tensioner narrower?

G

Of the 4 first issue you will see the 2 on the right are the earliest (sharp edge between bolt holes) and the 2 left have more rounded edges.
The ones with the set bolt on the right came about when the CL72 bikes came with the high pipes.
The pipes were in the way of the adjuster bolt.
I have had tensioners with 3 different wheel diameters but don't know what's up with that as the C/CB/CL engines were the only engines using this design and they all worked.
As you stated the cast cylinder assemblies came with a more narrow tensioner and I haven't figured out what's up with that either.
As you said the wheel could be damaged with a loose adjustment and also by us "pushing on the shaft and causing excessive pressure at the wheel and chain " which caused the wheel to become a sort of sprocket. ...............lm

I tipped out my box of old tensioners and was a little surprised with how many there were.



G

[Seadog]

...I've just found a needle roller bearing which would take the place of the bronze bush in the primary tensioner. 9/16 x 13/16 x 5/8"

Still around $6

So yes, it is possible to re-purpose a primary tensioner wheel as a cam chain tensioner wheel. Budget about $10 and an ½ hour to do the mods.

Somehow I knew you'd figure out a way. I would like to see you make a sprocket though….

[G-Man]

Seadog

Might have to cheat a little and get one of these.....

http://www.hpcgears.com/pdf_c33/13.10-13.11.pdf

G

...I've just found a needle roller bearing which would take the place of the bronze bush in the primary tensioner. 9/16 x 13/16 x 5/8"

Still around $6

So yes, it is possible to re-purpose a primary tensioner wheel as a cam chain tensioner wheel. Budget about $10 and an ½ hour to do the mods.

Somehow I knew you'd figure out a way. I would like to see you make a sprocket though….

[Seadog]

Seadog

Might have to cheat a little and get one of these.....

http://www.hpcgears.com/pdf_c33/13.10-13.11.pdf

G

Sure, but not as much fun for the rest of us!