dissasembly of rear shock coversI have spent a few hours this weekend disassembling several types of damper rods. There are a lot of photographs and I will try and organise them into a sensible order. In the meantime, here are a few pictures to keep everyone going.
Eventually I'll put all of the sequence of disassembly, restoration and reassembly into one big post. Enjoy! G  CB77 - Damper rod disassembled by graham.curtis, on Flickr  CB160 - Damper Rod disassembled.jpg by graham.curtis, on Flickr  CL77 - Crimped Parts disassembled.jpg by graham.curtis, on Flickr  CL77 - Threaded Complete disassembly.jpg by graham.curtis, on Flickr '60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160 '66 Matchless 350 '67 CL77 '67 S90 '77 CB400F A little bit more progress with the damper restoration. It seems that the original damper seals are impossible to get now so I have to improvise. Some of the seals I have look good enough to re-use but after 50 years I think it is a good idea to come up with a workable replacement.
CL77s 'appear' to have a damper rod of 10mm diameter (there are always exceptions) and a damper body bore of 27.2mm. CL72 shocks have a damper rod of 9mm diameter and a damper bore of 27.2mm The CB77 shocks I have dismantled have a rod diameter of 9mm with a damper bore of 26.2mm CB160s are unusual in that they have a 9mm damper rod and a 27.2mm damper All of this proves that whatever shock you dismantle you are going to have to measure what you've got in order to proceed. All seals are of 'double lip' design which means that you need a seal where the part that faces the oil has a lip backed up with a garter spring and the part which faces the outside world is a plain lip to keep dirt and dust out of the damper. The best I have been able to find so far are double-lip seals in 10 x 22 x 7 and 9 x 22 x 7 sizes. My plan is to machine up aluminium bushes which will convert these seals to work in a 27.2 or 26.2 bore, as required. The bush will have a wall thickness of 2mm or so and I hope will be able to accommodate a thin o-ring to seal it against the damper bore. My bush will be 10mm thick to match the original oil seals and this will provide a land for the seal to sit against. I shall make up some bushes in the next couple of days but here are a few pictures to illustrate where I am so far. G  CL77 - 10mm rod - Seal selection by graham.curtis, on Flickr  CL77 - 10mm Seal Comparison by graham.curtis, on Flickr  CL77 - 10mm Replacement Seal by graham.curtis, on Flickr  CL77 - 10mm New Seal - double Lip.jpg by graham.curtis, on Flickr
Last edited by G-Man on Mon Jan 30, 2012 1:38 pm, edited 1 time in total.
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160 '66 Matchless 350 '67 CL77 '67 S90 '77 CB400F Wow that’s incredible! I have a mill and a lathe but have no skill to use them. They just sit there. I wish I had your talent. I had to read the post a few times to grasp everything you were describing but I got it and this sounds great. I think it will work fine. I wondered how you were going to seal the bushing against the bore. The O-ring slot in the bushing should work great.
Are The Dream shocks the same? Just got the bushing finished and fitted with the new seals. I thought that I had purchased 1mm thick O-rings but they turned out to be 1.5mm. Had to go back and re-work the grooves.....
I'll take a look inside some Dream shocks soon. They should due very similar. Just found out that CB160 damper seals are still available. 9 x 27 x 10. They have a Honda part number too 91254-216-000 - incredible. None of the other bikes have seals listed, as far as I can tell. These will fit the CB160 plus early CL72 / 77 and maybe the Dream...  CL77- 10mm New Seal Holder by graham.curtis, on Flickr  CL77- 10mm New Seal Holder 2 by graham.curtis, on Flickr  CL77- 10mm Back side of seal holder by graham.curtis, on Flickr  CL77- 10mm seal holder in damper by graham.curtis, on Flickr Next job is to reassemble and then sort out some decent covers... 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 Last post for the time being. Here are the original CL77 damper bodies, rechromed with new sleeve nut and seal holder with new 10 x 22 x 7 seal inserted.
 CL77 - 10mm Reassembled Damper by graham.curtis, on Flickr 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
Graham,
I don't think it is too early to say that you have done an incredible job and documented it in a superb series of posts. Many will benefit from the knowledge and technique you've shared. On behalf of the honda305 community: Well done and many thanks!!! Sitting on the edge of the seat and looking forward to your field test reports on the finished products... -- Michael Stoic honda305.com
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