Speedo gearbox, back axle T140v

Magno

Member
Riding for 44 Years
Local time
Today, 13:03
Joined
Jul 6, 2013
Messages
65
Points
7
Location
London
First Name
Magno
My Ride
Triumph T140V
Hello Bikers
I have a back axle problem. The speedo gearbox on the right side is rubbing and wearing against the rear brake disc. I've taken apart the back axle assembly and it looks to me as if there should be a spacer or washer between the gearbox and the disc. Am I right in thinking there is a missing spacer or is there another way to lift the speedo gearbox away from the disc?
Any help much appreciated.
Cheers
 

Rocky

Still Rocking
Riding for 29 Years
Administrator
Staff
Local time
Today, 09:03
Joined
Jan 28, 2006
Messages
19,252
Points
893
Age
83
Location
Halifax
First Name
Rocky
My Ride
2006 T100 Bonneville
I think you may be right. I had a similar situation when I bought my 1970 T100S.
I don't have an answer for you, but I fitted a spacer of some sort (it was 20 years ago) and that solved the problem.
Do you have a parts book? That should show a spacer if there is one.
 

Magno

Member
Riding for 44 Years
Local time
Today, 13:03
Joined
Jul 6, 2013
Messages
65
Points
7
Location
London
First Name
Magno
My Ride
Triumph T140V
I think you may be right. I had a similar situation when I bought my 1970 T100S.
I don't have an answer for you, but I fitted a spacer of some sort (it was 20 years ago) and that solved the problem.
Do you have a parts book? That should show a spacer if there is one.


Many thanks Rocky,
I do have a workshop manual but it doesn't show a spacer. I just called my supplier in N England and he is posting me something that I hope will do the job.
Weather's great here and there's no time to lose.
 

Rocky

Still Rocking
Riding for 29 Years
Administrator
Staff
Local time
Today, 09:03
Joined
Jan 28, 2006
Messages
19,252
Points
893
Age
83
Location
Halifax
First Name
Rocky
My Ride
2006 T100 Bonneville
That's good news. I hope it works TUP
 

Rudie

Staff
Local time
Today, 13:03
Joined
Jun 25, 2017
Messages
236
Points
42
Location
GB
My Ride
Several
I do have a workshop manual but it doesn't show a spacer.
If you use the correct Triumph workshop manual for a T140V with a rear disc brake - 1976-1978 - it does, manual Section F14, page F21 is a full-page drawing of all the rear wheel components, the spacer is shown next to the speedo drive.

supplier in N England and he is posting me something that I hope will do the job.
You would help yourself more if you used a parts manual as well (e.g. free to read online at British Only Tech Library?). Not only is the same drawing there, all parts are numbered and listed on a parts manual's following page; in this case, the spacer is "12 37-7021 Washer - speedometer drive gearbox".

The Washer/spacer looks and fits like this:-

full
 

Magno

Member
Riding for 44 Years
Local time
Today, 13:03
Joined
Jul 6, 2013
Messages
65
Points
7
Location
London
First Name
Magno
My Ride
Triumph T140V
If you use the correct Triumph workshop manual for a T140V with a rear disc brake - 1976-1978 - it does, manual Section F14, page F21 is a full-page drawing of all the rear wheel components, the spacer is shown next to the speedo drive.


You would help yourself more if you used a parts manual as well (e.g. free to read online at British Only Tech Library?). Not only is the same drawing there, all parts are numbered and listed on a parts manual's following page; in this case, the spacer is "12 37-7021 Washer - speedometer drive gearbox".

The Washer/spacer looks and fits like this:-

full

Hello Rudie,

Thanks for the info. I did look at various parts and workshop manuals and finally found the solution. The washer you mention is exactly what I needed but on all diagrams it is shown on the outside of the speedo unit whereas it should be on the inside between the unit and the right hand spindle support spacer. THis means the unit is pushed further away from the disc giving it a couple of mm clearance. I didn't see this mentioned in any manual I could find and it took a while to figure out but it made sense to do it esp as the correct washer fits exactly into a recess on the inside of the speedo unit.
I just love this bike, it certainly keeps me guessing and helps fend off dementia. Who needs to learn a foreign language or how to play a guitar when you have an old Triumph?
Many thanks to all who offered advice.
Magno
 

Rocky

Still Rocking
Riding for 29 Years
Administrator
Staff
Local time
Today, 09:03
Joined
Jan 28, 2006
Messages
19,252
Points
893
Age
83
Location
Halifax
First Name
Rocky
My Ride
2006 T100 Bonneville
Thanks for the update TUP
I have run across incorrect diagrams in parts books too.
I mentioned that I had a similar problem too, and if memory serves correctly, I either had a missing washer or it was in the wrong place.
Reading this thread brings my memory back and I'm 100% sure I needed a correct washer/spacer too and the problem was solved.
I loved your language/guitar comment TUP TUP
 

56Karmann

Member
Riding for 53 Years
Local time
Today, 08:03
Joined
Dec 7, 2018
Messages
63
Points
7
Age
69
Location
Cobleskill NY 12043
First Name
Bob
My Ride
1977 Bonneville 750 T140
my problem is the rear master cylinder is rubbing against the tire
 

56Karmann

Member
Riding for 53 Years
Local time
Today, 08:03
Joined
Dec 7, 2018
Messages
63
Points
7
Age
69
Location
Cobleskill NY 12043
First Name
Bob
My Ride
1977 Bonneville 750 T140
and i only have a 76 parts cat. and and manual only shows rear drum no caliper
 

Rudie

Staff
Local time
Today, 13:03
Joined
Jun 25, 2017
Messages
236
Points
42
Location
GB
My Ride
Several
The washer you mention is exactly what I needed but on all diagrams it is shown on the outside of the speedo unit whereas it should be on the inside between the unit and the right hand spindle support spacer.
Nope, completely wrong.

The workshop manual, parts manual and my photograph are absolutely correct. If your bike requires a washer in addition to the spacer between the speedo drive and the wheel bearing, your bike also has the wrong spacer - look at my photograph, note the gap between the wheel hub and the speedo drive.

My photograph shows how all Triumph twins with the underslung rear caliper were new. If your bike is not like that, your bike has incorrect parts. The usual error is to transpose right and left spacers (37-7003 and 37-7006). Or, your bike has two spacers the same, it has two short spacers.

Another possible - though less likely - error on your bike is the caliper carrier is bent.

I am surprised other '76-'78 twin owners did not pick up the error in your post earlier. :(
 

Rudie

Staff
Local time
Today, 13:03
Joined
Jun 25, 2017
Messages
236
Points
42
Location
GB
My Ride
Several
my problem is the rear master cylinder is rubbing against the tire
I have posted a possible suggestion in your 1977 Bonneville resto thread. Please post the make and model of the tyre fitted on your bike.

i only have a 76 parts cat.
only shows rear drum no caliper
You do not. Meriden published two parts catalogues in in 1976 - in February and August. Both are online in several places - e.g. British Only Tech Library - neither shows a rear drum brake (last fitted to 1975 twins that were not exported new to the US).

manual only shows rear drum no caliper
If you mean a workshop "manual", the online version covers all '73-'78 twins and has several subsections in "SECTION F | BRAKES, WHEELS AND TYRES" dealing with both disc and drum rear brakes.
 

Wavemaker

Member
Riding for 46 Years
Local time
Today, 13:03
Joined
Dec 5, 2020
Messages
13
Points
7
Age
67
Location
Brisbane
My Ride
1976 Triumph Bonneville
I have posted a possible suggestion in your 1977 Bonneville resto thread. Please post the make and model of the tyre fitted on your bike.


You do not. Meriden published two parts catalogues in in 1976 - in February and August. Both are online in several places - e.g. British Only Tech Library - neither shows a rear drum brake (last fitted to 1975 twins that were not exported new to the US).


If you mean a workshop "manual", the online version covers all '73-'78 twins and has several subsections in "SECTION F | BRAKES, WHEELS AND TYRES" dealing with both disc and drum rear brakes.
F15 Rear Wheel. Page145/217.
 

56Karmann

Member
Riding for 53 Years
Local time
Today, 08:03
Joined
Dec 7, 2018
Messages
63
Points
7
Age
69
Location
Cobleskill NY 12043
First Name
Bob
My Ride
1977 Bonneville 750 T140
first chance I've had to check my thread. thank you I did learn of the two catalogues. i also found that the air filters as well as hardware items were wrong. Air boxes won't fit carb to box connectors were also wrong. but now I'm having trouble with fuel and air/choke cable placement, I've checked several photos of 77 T140's with several different cable routes. just can't get throttle or choke to work smoothly.
 

56Karmann

Member
Riding for 53 Years
Local time
Today, 08:03
Joined
Dec 7, 2018
Messages
63
Points
7
Age
69
Location
Cobleskill NY 12043
First Name
Bob
My Ride
1977 Bonneville 750 T140
Using a 78 parts catalog I removed spacers called for in April 77 catalogue and all's well with rear brake. still looking for rear brake hard line 60-7007 many distributers say they have iy but always out of stock.
 

Wavemaker

Member
Riding for 46 Years
Local time
Today, 13:03
Joined
Dec 5, 2020
Messages
13
Points
7
Age
67
Location
Brisbane
My Ride
1976 Triumph Bonneville
Hello Rudie,

Thanks for the info. I did look at various parts and workshop manuals and finally found the solution. The washer you mention is exactly what I needed but on all diagrams it is shown on the outside of the speedo unit whereas it should be on the inside between the unit and the right hand spindle support spacer. THis means the unit is pushed further away from the disc giving it a couple of mm clearance. I didn't see this mentioned in any manual I could find and it took a while to figure out but it made sense to do it esp as the correct washer fits exactly into a recess on the inside of the speedo unit.
I just love this bike, it certainly keeps me guessing and helps fend off dementia. Who needs to learn a foreign language or how to play a guitar when you have an old Triumph?
Many thanks to all who offered advice.
Magno
Totes agree regarding firewall on dementia.
 

Wavemaker

Member
Riding for 46 Years
Local time
Today, 13:03
Joined
Dec 5, 2020
Messages
13
Points
7
Age
67
Location
Brisbane
My Ride
1976 Triumph Bonneville
If you use the correct Triumph workshop manual for a T140V with a rear disc brake - 1976-1978 - it does, manual Section F14, page F21 is a full-page drawing of all the rear wheel components, the spacer is shown next to the speedo drive.


You would help yourself more if you used a parts manual as well (e.g. free to read online at British Only Tech Library?). Not only is the same drawing there, all parts are numbered and listed on a parts manual's following page; in this case, the spacer is "12 37-7021 Washer - speedometer drive gearbox".

The Washer/spacer looks and fits like this:-

full
20210316_154403.jpg
Here is the page in my Clymer manual. Damned if I can spot the spacer. Please help me out.
 

Rudie

Staff
Local time
Today, 13:03
Joined
Jun 25, 2017
Messages
236
Points
42
Location
GB
My Ride
Several
View attachment 49379
Here is the page in my Clymer manual. Damned if I can spot the spacer. Please help me out.
Meriden published two parts catalogues in in 1976 - in February and August. Both are online in several places - e.g. British Only Tech Library
The Clymer manual illustration is taken from the parts catalogue published in February 1976, that contains so many mistakes Meriden reissued it in August 1976; if you find the same drawing in the second edition, the spacer is beside the speedo drive.
 

Wavemaker

Member
Riding for 46 Years
Local time
Today, 13:03
Joined
Dec 5, 2020
Messages
13
Points
7
Age
67
Location
Brisbane
My Ride
1976 Triumph Bonneville
The Clymer manual illustration is taken from the parts catalogue published in February 1976, that contains so many mistakes Meriden reissued it in August 1976; if you find the same drawing in the second edition, the spacer is beside the speedo drive.
Gooday Rudie. Thanks for that. I'll have to up date, won't I? .
 
Premium

Support TriumphTalk by becoming a Premium Member.

 What You Get

Donate

 

 

Search

Top Bottom