Disk brake conversion

TeddyG · Sep 18, 2023

I'm considering purchasing a 73 Commando and wondering what components others have used to fit a modern front disk caliper. I have axial mount Brembo calipers and master cylinder/lever from an Aprilia, but need to know what caliper mounting plate and aftermarket rotor will work. Thank you

Tornado · Sep 18, 2023

You will likely need a custom/homemade caliper bracket for you setup. Also, changing the MC means changing the switchgear on the right side handlebar.
Alternatively there are modern disk brake kits available, some of which keep oem switchgear, from different vendors for Comando.

See Colorado Norton Works or
Forum member Madass140's web page here for kits:

tritonmotorcycleparts.com

BruceB · Sep 27, 2023

I also recently went through this decision process and opted for the upgrade kit offered by tritonmotorcycleparts (Don Pender). The installation was very straightforward, everything fit beautifully, and you get to keep your existing switch gear.
In use, it has a nice progressive feel with two finger braking, and with a fistful you can lock the front wheel. It has transformed my riding experience. Highly recommend

And Don was very helpful and responsive to emails.

Stephen Hill · Sep 29, 2023

Does Don's upgraded master cylinder use a front brake switch?

Tornado · Sep 30, 2023

Stephen Hill said:
Does Don's upgraded master cylinder use a front brake switch?

Pretty sure it does as it is derived from a commonly available bike.
Try asking him direct in a PM to madass140.

Stephen Hill · Oct 1, 2023

I thought BruceB could answer this, as he installed one.

nortonmews · Oct 2, 2023

Yes, Don's conversion does have a brake light switch

BruceB · Oct 2, 2023

nortonmews said:
Yes, Don's conversion does have a brake light switch

Hi Stephen, yes Don's brake MC does have a brake switch. As the MC assembly is more compact than the OEM assembly you'll have to pull a bit more cable out from the headlight (if you have enough to spare), plus the spade connectors on the MC switch are of the narrower type, so you will have to replace the female connectors on the harness, or make up a pigtail. Lots of ways to accomplish it, but the main thing is that there is a switch and it's relatively easy to connect into the existing harness.

laurentdom · May 9, 2025

Hi All,

I've just replaced my standard Norton caliper and the Brembo master cylinder with the BERINGER Classic components. It's a direct and easy fit on the RH fork leg and handlebar.

Result is amazing in terms of braking power but also progressivity and predictability which I was looking for. And to me, the look is not too much inadequate with our bikes.

You cand find details and pictures searching for instance "Beringer Classic Norton" on the Net. Beringer is a French company but may have resellers in other countries or is ready to sell directly all over the world.

ashman · May 9, 2025

There are a few great replacement front brake kits around that are all bolt on with mounting brackets and all, it all depends on how deep your pockets are and your use, when my stock brake system let me down in 2 minor accidents the last one I suffered a fractured left arm and broken left thumb was time to replace the old system completely 10+ years ago while recovering, I ended up going for a full Grimica system from RGM, 12" semi floating disc, Grimica caliper with mounting plate, SS brake line and Grimica MC with a longer leverage leaver, this whole set up cost was just a tad over $500 at the time, this has changed my whole front brake to a fully working system and one finger operation if you want to use one finger, for my light hotrod Norton its great when you need to brake hard in an emergency, I am not a heavy user of brakes but its great to know the bike will stop when needed, 10+ years now on the Norton and still working as good as the day they been installed.
As I say there are many great front brake kits around from Brembo, to Madass upgrade kit and more, I went with the Grimca system as it was the right price for me at the time with fast delivery to my front door, Grimca brakes have been around for a very long time including racing, but its up too you in what you want, I am very happy with my set up and how good they work for the money I spent.

acotrel · May 9, 2025

The front brake on my Seeley 850 is two Lockheed AP calipers mounted on Ceriani forks operated by a master cylinder designed for one caliper. The brake is one-finger operation which means my other fingers are wrapped around the quick action throttle. The calipers are held on by home-made brackets and Unbrako screws, which are not lock-wired - so I often check them for tightness. The main problem I had was finding pads which worked properly. The front brake establishes how fast you can ride, along with the steering geometry and weight distribution. The rider adjusts to the bike. If it feels wrong, you will be slow.
With experience, you usually know the changes which need to be made to enable higher speeds.

ashman · May 9, 2025

Well of course when you race you need good brakes, but this is a road going bike Al, and a good set up single disc can work as good as twin disc, modern brakes are so much better than 50 year old brake set up, the stock Norton disc worked great when they were new but after a few years they become sh it and after 40 years can become very dangerous to your health, mine worked OK with a few rebuilds over time and a SS brake lines make a big improvement over the rubber line, they swell up and can block the flow of BF, but of course the stock brake will one day let you down without warning when you need them, as mind did, but so many presist with the stock set up for originality but the 12" systems look so good and work so much better if done right with full modern brake system, your safety and life is so much better than old brakes I say.

NORTSTER1974 · May 9, 2025

ashman said:
There are a few great replacement front brake kits around that are all bolt on with mounting brackets and all, it all depends on how deep your pockets are and your use, when my stock brake system let me down in 2 minor accidents the last one I suffered a fractured left arm and broken left thumb was time to replace the old system completely 10+ years ago while recovering, I ended up going for a full Grimica system from RGM, 12" semi floating disc, Grimica caliper with mounting plate, SS brake line and Grimica MC with a longer leverage leaver, this whole set up cost was just a tad over $500 at the time, this has changed my whole front brake to a fully working system and one finger operation if you want to use one finger, for my light hotrod Norton its great when you need to brake hard in an emergency, I am not a heavy user of brakes but its great to know the bike will stop when needed, 10+ years now on the Norton and still working as good as the day they been installed.
As I say there are many great front brake kits around from Brembo, to Madass upgrade kit and more, I went with the Grimca system as it was the right price for me at the time with fast delivery to my front door, Grimca brakes have been around for a very long time including racing, but its up too you in what you want, I am very happy with my set up and how good they work for the money I spent.
View attachment 119693

Ash, Your bike has been leaning against that post far too long. Over here in the USA they would have given you a ticket or towed it by now!

MexicoMike · May 9, 2025

FWIW, many years ago I changed my '73's OEM mastercylinder (after two sleeved MC failures) for the CNW Brembo MC (with the switchgear adapter). I Installed SS brake lines and Ferodo Platinum pads in the OEM Lockheed caliper. The brakes are excellent with good feel/plenty of stopping power. In fact, any additional braking power would just make it easier to lock the (OEM size) front wheel. I cannot speak for extended high speed use of this system - as in racing/track use but there is no lack of braking power/feel for street use and I have never felt the need for increased braking ability.

ashman · May 10, 2025

NORTSTER1974 said:
Ash, Your bike has been leaning against that post far too long. Over here in the USA they would have given you a ticket or towed it by now!

My side stand foot broke (cast iron) so leaning the bike on anything handy, after building the Commando/Featherbed back in 1982 I didn't have any stand at all for about 20 years so I used whatever was close to prop it up, the side stand is a clamp on side stand but one day might make a better side stand for it.

acotrel · May 10, 2025

With a race bike, the front brake determines how fast you can ride, however everybody else is riding close to the same speed. So unless the brake has the tendency to lock as it heats up, or fades seriously, if it does not work effectively you simply ride to suit it. With road bikes, everything is much more situationalist, so you are never really ahead of the game. The first time you road race is the most dangerous. After you have done a few laps, your mind adjusts to what is happening. If you are a good road rider, you are probably safer than people who begin racing with MX bikes, go-karts or cars. Being situaltionalist helps, but being systematic is much better. I never feel safe when riding on public roads, but I always feel safe on a racetrack.

acotrel · May 10, 2025

I once won a race with a Suzuki Cobra. It was a handicap race at a club meeting, in which the whole field had to be passed. Spectators could smell the brake linings burning as I passed the pits. Every corner was a high speed glide. There was another guy on a Gold Star BSA - I almost knocked him off his bike in one corner. I passed him at very high speed, and had no way of braking or missing him, if he had changed line.

Disk brake conversion

Similar threads