Conrton Commando dual-disk upgrade

Greetings, I am headed up to KC this weekend, to get my new project bike, a 72 750 Combat. Will have more details and a condition report on my return, I know the bike has been sitting for years and is in for complete overhaul.

Would like for this Norton to have dual-disk in the front, as I have been spoilt by the powerful brakes on my (modern bike). Has anyone a recommendation or experience with this upgrade for a street bike? Norvil offers a 12" dual kit p/n 069808S, "two 12" superlight disks to fit straight onto a twin hub". A bit pricey $$ but, building this bike for a keeper - and I will put some miles on it. Anybody use this kit, or have recommendation regarding Commando dua disk upgrades. Would like to use the Norton hub. thanks

jjeff441 said:

Greetings, I am headed up to KC this weekend, to get my new project bike, a 72 750 Combat. Will have more details and a condition report on my return, I know the bike has been sitting for years and is in for complete overhaul.

Would like for this Norton to have dual-disk in the front, as I have been spoilt by the powerful brakes on my (modern bike). Has anyone a recommendation or experience with this upgrade for a street bike? Norvil offers a 12" dual kit p/n 069808S, "two 12" superlight disks to fit straight onto a twin hub". A bit pricey $$ but, building this bike for a keeper - and I will put some miles on it. Anybody use this kit, or have recommendation regarding Commando dua disk upgrades. Would like to use the Norton hub. thanks

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Master cylinder is as important as the disks in getting it to stop right.

The stock master cylinder on the Norton is grossly oversized. Either by sleeving or replacing with a properly sized M/C you can achieve a very good front brake with a single disc. I have a 12 " floating rotor with a Gremica caliper and a 11mm M/C. I really can't tell any appreciable difference between it and my twin Brembos on my BMW K75.

Go to: http://www.vintagebrake.com/mastercylinder.htm. This will give you the proper ratio of Caliper to M/C.

jjeff441 said:

Greetings, I am headed up to KC this weekend, to get my new project bike, a 72 750 Combat. Will have more details and a condition report on my return, I know the bike has been sitting for years and is in for complete overhaul.

Would like for this Norton to have dual-disk in the front, as I have been spoilt by the powerful brakes on my (modern bike). Has anyone a recommendation or experience with this upgrade for a street bike? Norvil offers a 12" dual kit p/n 069808S, "two 12" superlight disks to fit straight onto a twin hub". A bit pricey $$ but, building this bike for a keeper - and I will put some miles on it. Anybody use this kit, or have recommendation regarding Commando dua disk upgrades. Would like to use the Norton hub. thanks

Click to expand...

Dual discs on street bikes have always seemed to me to be a bit of hoopla. That goes double on a 400lb bike with 50hp. Norton got the ratio on the brake wrong to start with and never got around to fixing it. It's easy to do and if you have the chance to ride a bike with stock disc and caliper and a reduced master cylinder you might be amazed at the improvement. Add a stainless line and decent modern pads and you and it may be sufficient for you. Lots of people say they could do two finger stoppies with a well setup single disc Commando. The hoopla part comes from marketing a bike that looks like a race bike. Race bikes need dual discs for swept area and especially for heat dissipation. They can get into a 'heat debt' because they don't get the time necessary to cool things down between mashing the brakes lap after lap. Maybe a 12"-13" single disc is an option and you can leave the front wheel orignial, as you said.

jjeff441 said:

... Anybody use this kit, or have recommendation regarding Commando dua disk upgrades. Would like to use the Norton hub. thanks

Click to expand...

I researched to extremes how to improve the front brake on my bike, and I looked into dual front disk set-ups. The one that looked the best to me was Norman White's brembo kit (http://www.normanwhite.co.uk/prod01.htm).

In the end, though, I went with a home-made set up (too miserly to buy CNW's upgrade) using a Suzuki 310mm single disk (eBay for $35) and Brembo calliper (eBay for $45). I had to have adapters made for the disk and the calliper bracket. This was the most expensive item. I'm also using the Andover Norton 13mm master cylinder and stainless line upgrade. I think it is a better option than a sleeved Lockheed master-cylinder and it's about the same cost.

It works fine for me and I have to agree with other posters that dual disks probably aren't necessary, but they look cool.

jjeff441 said:

Norvil offers a 12" dual kit p/n 069808S, "two 12" superlight disks to fit straight onto a twin hub".

Would like to use the Norton hub.

Click to expand...

There's no Norvil "twin disc" kit that uses the standard Norton hub, as far as I know? (the "twin hub" is Norvil part 063700, I believe?: "063700 HUB - WHEEL - FRONT TWIN - COMPLETE WITH BEARINGS AND SPACER - £198.57 (GBP) http://www.norvilmotorcycle.co.uk/wheelhub.htm" )

Re: Norton Commando dual-disk upgrade

Firstly, thanks for the response. Regarding the dual disk configuration for a street Norton, just want to pass along that after selling my last Norton, I picked up a Ducati ST3. My enquiry is based on the excellent brake feel on this bike (do not chatter or fade, not grabby and great stopping power). At the Cal. Superbike School they taught us to "forget about the rear brake - dont even use it" and, I will adnit, it's hard to break these habits when I ride vintage bikes. I am not trying to build a Commando with a "race look", but I am a person that thinks a properly sorted and built Commando can be a good cross country rider, if well maintained. I just want stopping power.

Here's what I found so far as far as options:
The Norvil kit is $$$ at 1219UK - 2020USD
Norman White kit at 930UK - 1541USD (didn't know about this, and thanks for the suggestion)
CNW single rotor kit at 1095US
Upgrade my master cyl to 13mm bore 210, rebuild my caliper 306, rotor 210

Regarding my caliper, I remember back in auto shop brake class, we were told that Lockheed had invented the disk brake for aircraft use. That gorgeous Norton-Lockheed casting on the caliper has a lot of intrinsic value.

However, the braking on my last Commando was "good", and the front disk on the Bonneville was "adequate" (at best). This Norton will have brakes that are "superb" to "excellent" is the goal. Appreciate the feedback!