My CB77 km/hr speedo stopped working, had a look and the drive end at the wheel fitting had sheared from the cable. I replaced the inner cable and now the speedo is reading way over toward maximum speed even when riding steadily. As far as I can see there is only one speedo inner cable and it seems to be installed. I can't see why just changing the cable could have introduced a multiplier and suspect it could be a speedo fault but why would that happen now at the same time as the cable failure unless that caused the failure.
Has anybody seen this before or could suggest a reason why? Many thanks
speedo cable
Masonmart
There are two reasons for cable falure. One is a problem in the speedo - dry bearings on the input or in / around the magnetic drive cup inside, the other is a dry cable leading to 'wind-up' and subsequent 'crazy needle syndrome' or shearing of the cable.
Sounds like you have a speedo problem caused either by a lack of lubrication in the speedo or via a tight cable 'catapulting' the speedo as it rapidly unwinds from the stiction.....
You can usually clean / lube the speedo input bearing but it sounds like your problem has progressed further into the speedo.
Either the return spring will have been damaged or the aluminium 'eddiy current' (magnetic) drive is dirty / damaged. Both can be seen in the middle of my picture.

G
There are two reasons for cable falure. One is a problem in the speedo - dry bearings on the input or in / around the magnetic drive cup inside, the other is a dry cable leading to 'wind-up' and subsequent 'crazy needle syndrome' or shearing of the cable.
Sounds like you have a speedo problem caused either by a lack of lubrication in the speedo or via a tight cable 'catapulting' the speedo as it rapidly unwinds from the stiction.....
You can usually clean / lube the speedo input bearing but it sounds like your problem has progressed further into the speedo.
Either the return spring will have been damaged or the aluminium 'eddiy current' (magnetic) drive is dirty / damaged. Both can be seen in the middle of my picture.

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
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
MM
Good that you were able to recover the situation. You should be able to get someone to fix that unit but if you are ever tempted to part with it, please let me know. I have rebuilt a few.
G
Good that you were able to recover the situation. You should be able to get someone to fix that unit but if you are ever tempted to part with it, please let me know. I have rebuilt a few.
G
masonmart wrote:Thanks G-Man, correct, it was the speedometer. It started making a lot of noise and then the rev counter started acting up. It was a very low km but very old speedo. Luckily I had a spare one and it works fine now.
The bikes are going beautifully though.
MM
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
- Jims65CA77
- honda305.com Member
- Posts: 170
- Joined: Fri Jul 05, 2013 3:31 pm
- Location: New Jersey
Cable or speedo?
G
G
Jims65CA77 wrote:While on the subject of lubing and cleaning... is there a post somewhere on the "how to" mentioning the type of lubricant and "where" to lube? My bike is the CA77.
Thanks!
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F