Triumph Bonneville T140 Front Brake Service - Part 1: Disassembly of calliper and master cylinder

I am performing a full strip down and service of the front brake system on my Triumph Bonneville T140E.
In this first video I drain the system, remove the front brake calliper and front brake master cylinder and strip them down.
This is part 1 of a 4 part series:
Part 1: removing the front brake master cylinder and brake calliper and stripping them down.
Part 2 - cleaning the brake parts in an ultrasonic cleaner and checking all for wear or damage.
Part 3 - Front brake calliper reassembling: fitting new seals, reassembly and refitting on the bike
Part 4 - Front brake master cylinder reassembly: fitting new seals and washers, reassembly, setting the cylinder length, refitting on the bike, refilling and bleeding the brake fluid.
You can download a number of useful resources from my "Buy Me a Coffee" page - all free with no catches - it is just a convenient place to make downloads easily available (but there is an option to buy me a coffee if you enjoyed this video and feel overwhelmed with gratitude) - including:
T140 service checklist;
T140 torque settings;
T140 parts catalogue
and other items: www.buymeacoff...

[@jamesa6272]

I started my front brake system today with the help of your videos. The pistons were tough to get out. Got them out with air and literally poured chocolate milk/grime and dirt out of the caliper

[@SongsFromTheSaddle]

Very satisfying - you know it was worth doing the job when that happens.

[@chamberizer]

I have a 1973 Tiger 750. I couple of years ago my front brake was dragging not releasing all the way. I was watching a KZbin on automotive brakes & it was suggested to replace the flexible brake hose, because when it gets old it can act like a check valve & cause the brakes to stick. I replaced the two pieces of flexible line on the front brake & it fixed the problem. New calipers I think are available, made by Girling? Years ago I rebuilt the master cylinder. Your method with the Drumel tool sounds good. I used a pencil with an eraser & wrapped a piece of emery cloth around the eraser & used it to hone the cylinder.

[@SongsFromTheSaddle]

Thanks for sharing. I think I'll treat mine to new hoses this year.

[@desmondburnett4036]

No need to remove the front wheel. Just undo the two studs holding the calliper assembly.

[@DodgyBagehot]

When i rebuilt brake calipers, i used bike pump to get out pistons, but clamped the one that was coming out first. Allowed me to blow out the one that was stuck. Didnt have piston wrench...

[@jamesa6272]

You explaining how to do this is Gold. Thank you very much! I to have the same problem with my 78 t140v. The front brake light switch is hanging on by a thread and barely working.

[@SongsFromTheSaddle]

Glad it helped

[@daveco1270]

Is the bottom fork cap on the left side front fork cracked? I'm not sure if you mentioned that in the video or not.

[@SongsFromTheSaddle]

Well spotted. Yes, I replaced it.

[@bm7760]

I really have to replace my front master cylinder too. Drags for a good while after use and braking is poor. Also, I counted six connections in the front line between master and caliper! I want to replace that with a single braided line. My question is, do you have anywhere you'd recommended I source the parts? Thanks.

[@SongsFromTheSaddle]

Not for replacement brake lines. For most of my classic bike parts I go to www.classicbikeshop.co.uk

[@garywhiteman8798]

I’ve put a flitting front disc on mine, brakes still awful but slightly better, I guess I’ve just got to get used to a classic bike as it’s my first one

[@SongsFromTheSaddle]

Hi Gary. I'm guessing you mean a floating front disk. See my later video on changing pads - I'm now very happy with the brakes on my T140

[@rickconstant6106]

The biggest improvement I made to the front brake on my T140V was replacing the original 5/8" bore master cylinder with a 13mm stainless steel one. It screws straight in as a direct replacement, with all the same fittings, but gives a much better feel and, effectively, 50% more leverage, and at about the same price as the standard one.

[@bm7760]

​@@rickconstant6106 Can you explain where I'd get this for mine? Thanks.

[@rickconstant6106]

@@bm7760 I got mine from FD motorcycles in Dunmow, where I buy all my Triumph parts, but I've seen them advertised by several stockists of T140 parts. Try searching T140 master cylinder 13mm.

[@lakemarine484]

I'm rebuilding my'78 T140E and mine has a 3/32 Allen set screw that seats in the keyway on the cylinder O.D thread. The Allen screw is stuck. What year is yours and and have you ever seen the style im talking about?

[@SongsFromTheSaddle]

Are you referring to the grub screw which locks the cylinder thread? They are renowned for seizing in. Try soaking it in penetrating oil. You could also try applying a bit of heat. Watch the later videos in which I strip, clean and rebuild the master cylinder.

[@rickconstant6106]

The first time I overhauled the front master cylinder on my 78 T140V, 29 years ago, the grub screw was seized and corroded to the point where it was impossible to unscrew, so I carefully drilled it out and retapped the hole to the next size up. Instead of using a grub screw, I replaced it with a stainless steel cap screw, with the tip ground down to locate in the cylinder barrel slot, and coated the threads with brake grease to avoid a repeat of the seized screw. Although the head of the screw protrudes, it is underneath and is not noticeable, but is a lot easier to remove for service.

[@ericsmith1066]

Did u notice your spindle clamp is cracked?

[@SongsFromTheSaddle]

Well spotted Eric! Yes, I was aware of this and had a new one ready to fit. You'll see on the reassemble video I fit a new one. It was cracked on the outside, but not right across. I believe its a common problem (That's both of mine replaced now).

[@ericsmith1066]

@@SongsFromTheSaddle aye just replaced one of mine👍🤣

[@mmark8394]

Spindle clamps don't crack it's the muscle men who don't know when to ease up , a good sign to avoid, rocker covers also suffer and what other hidden atrociousitis lurk for the unwary

[@DodgyBagehot]

Glad to see others pointed this out. I was worried about that. Returning a bike to service, both of mine were cracked all the way through. From what I read, originals were cast, prone to crack. Can buy replacements milled out of solid billet (?) . Unlikely to crack. Think it was from low brow customs or classic British spares.