Street Twin Brakes

Caliper on and 12.7mm (2022, 900 Bonnie) 1/2 inch marked master cylinder on. The mater cylinder is exactly the same except for the bore so mirrors, reservoir and brake swith all go on no problem. First bleed done - took some patience to get rid of the worse of the air pockets - but rain stopped play so I'm gonna bleed it again.

Lever as expected. Very slightly firmer than standard. The old brake fluid was a little cloudy.

I still have an ebc floating disc and new HH disc pads to go but so far so good. I have no centre stand so I'm gonna get an Abba stand or something to help me keep the bike solid so I can get the front wheel out safely.

Photos to come once the job is completed.

 

Nice honest write up, thanks.
Please do post a test ride impression once its all up and running

 

A vacuum bleeder is your friend and once mastered it makes your life easier.

I have one something like this....

https://www.machinemart.co.uk/p/blue-spot-brake-bleeder-and-vacuum-pump-kit/

 

Wow! That does look trick and I'm always looking for more tools! Many thanks for the thought.

 

Make sure the bleed nipple isn't leaking (air) when "your pulling the fluid"?
If it is, remove the nipple and give it x3 wraps of ptfe tape, on the threads only

Job done.

 

Don't forget these can also be used for vacuum (reverse pressure) testing i.e. seals and chambers.

 

You know i have two of those and never used them

 

Good tools @joe mc donald and I've used mine for all sorts.
The younger generation wont have a clue what I'm talking about but it was interesting using one and watching how the advance and retard diaphragm performed on the points baseplate. Any leaky pipework can soon be safely sorted without popping anything i.e. applying compressed air ... oh b0ll0cks, I wish I hadn't done that ...... a few of us have been there no doubt.... moi, oh no .... but maybe

 

@Eldon Perhaps i will get around to trying one out soon. My boy used them on is track bikes 675's so i got one then he got me a second.

 

Bonnie master cylinder.

 

Sorry, lever!!

 

Lever pull

 

On setting #4 yes?

 

On 3 Eldon.

 

Sorry mate, yes 4.

 

I have also bled them again this morning and the lever firmed up a little more. In between the rain I also went out for a 25mile run. Lever consistent, no leaks. Definitely more stopping power. I never thought the standard brake was that bad tbh. 2 up (I'm a 17st fat bastard and the wife is a gorgiously well proportioned 12st) and pulling her down from a ton there was no real reserve power in the brakes - you were using the system, with the rear brake to 90% or so of its potential. Now the engine is done, suspension is done I can ride her swiftly and know I have some 'brakes in my back pocket'. I'm happy - after all, she is no ZXR or Speed Triple and there is a reason why I no longer have such bikes. Basically, I'm getting old and have too many old injuries!!! Lol!!

 

All bedded in now (after about 300 miles). The 3 pot nissen works great and is effortless on the fingers. The caliper, 12.7mm master cylinder (gen 2 900 bonnie) EBC floating disc (for a Street Cup) and HH pads have really made a difference and feels 'factory fitted'. Very happy.

 

I've had a look round for a used Gen 2 Street Twin master cylinder to upgrade my current 11mm mc to 12.7mm. They're pretty thin on the ground.

However there are a couple of master cylinders from the Thruxton 1200 RS (part number T2025933).
Would anyone happen know the bore of that mc?

 

Check, but I am pretty certain any of the Brembo caliper equiped gen2 900 LC master cylinders would be 12.7mm.

The Thruxston, being twin disc is likely to be 14mm but please check.

I have not tried a 14mm myself (on a 3 pot caliper) but I have read testimony (from this forum or Triumph Rat) from someone who has. This gent says it works.

So for being vague but I hope this helps.