Anyone here know of a way to improve front disc brake on '72 Commando and still be mostly stock ?

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richmont

richmont

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Any advice from anyone on improving stopping power on a '72 Commando while still being as close to stock as possible /
 
Resleeve the MC and use Fedoro Platinum pads on my '74 850...braking is decent...I'd estimate about 80% as good as my 2013 Bonneville front brake.
I used the Resleeve Kit from Madass140 on this site...comes with a stainless front hose.
 
I agree that the resleeve and Ferodo pads (and SS brake lines) will make a substantial improvement. However, I had a resleeve fail and leave me with no front brake at all while riding so I'm a little gun-shy of resleeves! ;) A Brembo MC (available from CNW) will make the front brake perform like a modern front brake but, of course, it doesn't look stock. :(
 
38K+ miles on my resleeve and no issues other than better braking. SS hose and Ferodo pads also.
 
Yup, I had my orig master resleeved, without repaint... looks old!
Ferodo pads, All the brake that front tire can handle.
 
I had a Miles M/C resleeve done many years ago. With the Ferodo pads and SS line I was happy for many years. A couple years ago however, the M/C would lock up if the bike was parked outside in the hot sun. Ice on the M/C would return things to normal so I could get home.
I ended up going with one of Madass140 brake set ups, doesn't look stock, but other than the M/C, i can't see it while riding any way. Plus, it is plenty powerful and very controlable.
 
As parroted above but with the RGM resleeve kit, Ferodo pads and SS line improve the braking. +40K miles and counting.
I never experienced the lockup on hot days but I refrained from painting the M/C body black and kept it in the raw aluminum state. My guess is the black absorbs so much heat from the sun that it pressurizes the system. Use a bandana over the M/C if you are going to walk away from the bike on hot sunny days.
Cheers,
Thomas
 
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As cyclegeezer says, Andover Norton sell a stock, reduced diameter cylinder if you don’t want to go down the re sleeve route.
I use the RGM re sleeve kit which is great. Madams get great reviews too. All these options retain a stock master cylinder. I’m sure black stainless pipe would help too.
 
+1 on the re-sleeved OEM Master Cylinder, in keeping with the OP's wishes ;)
I've used RGM's kit on 3 bikes without any issues, but I believe Madass's kit is just as effective and easier to fit.
the RGM kit comes with instructions which emphasise the importance of careful adjustment - It could be that the hot weather issues reported may be due to a marginal setup?
We're fortunate in the UK to not have to make allowances for hot weather :rolleyes:
 
Pads can surprisingly make a big difference, use only friction materiel suitable for cast iron if using the standard disc, the maker of the pad will tell you if you ask.
 
After my orginal front disc brake system tried to kill me about 5 years ago but lucky only broke my left arm and thumb, while recovering I decided to upgrade my whole front brake system, I went for a full Grimaca system, 12" floating disc, calipa, master cylinder and SS brake line, its one of the best improvement I have done to my brake system, one finger operation if I want, brakes that work the way they should, yes its not orginal looking but it looks better, stops great without effort.
Even doing a resleeve and better pads and SS line it still wouldn't work as good as what I am now running, I would never go back to the original front disc brake system, my life is more important than keeping it orginal looking but then my whole Norton hasn't been orginal since the early 80s, having modern brakes on a old bike is so good.
Keeping your brakes orginal is all good back in the 70s, but having your brakes let you down when your life depends on them.

Ashley
 
ashman said:
After my orginal front disc brake system tried to kill me about 5 years ago but lucky only broke my left arm and thumb, while recovering I decided to upgrade my whole front brake system, I went for a full Grimaca system, 12" floating disc, calipa, master cylinder and SS brake line, its one of the best improvement I have done to my brake system, one finger operation if I want, brakes that work the way they should, yes its not orginal looking but it looks better, stops great without effort.
Even doing a resleeve and better pads and SS line it still wouldn't work as good as what I am now running, I would never go back to the original front disc brake system, my life is more important than keeping it orginal looking but then my whole Norton hasn't been orginal since the early 80s, having modern brakes on a old bike is so good.
Keeping your brakes orginal is all good back in the 70s, but having your brakes let you down when your life depends on them.

Ashley
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Ok, 1 finger versus 4, or elderly not with an iron grip anymore, ok....
But with the improved friction coefficient of Ferodo Plats, and increased pressure from sleeving, I can lock (using my whole hand) the front on dry asphalt. And it’s linear progressive. Certainly not a one finger race bike brake, but it allows me to stop with all modern vehicles.
Not trying to detract all you resto-mod guys, cuz, whatever you like, you like. But playing the “safety card” here is inaccurate.
 
If you insist on keeping the original caliper , you could cut a step in the pistons over 130 -140 deg. ,
like Porsche , Mercedes , Alfa and others did when they where still using fixed 2 piston calipers .
( remove 1 mm from 6 o'clock to 10.30 on leading edge )
It will improve the brake performance , but it is not a miracle solution either :

Anyone here know of a way to improve front disc brake on '72 Commando and still be mostly stock ?


Anyone here know of a way to improve front disc brake on '72 Commando and still be mostly stock ?


Anyone here know of a way to improve front disc brake on '72 Commando and still be mostly stock ?


Anyone here know of a way to improve front disc brake on '72 Commando and still be mostly stock ?
 
Hello Jan, is there a way to fit them into caliper hole , I mean cut side on leading or trailing ?
thank you for posting , Pierre.
sorry , I did not look at the sketch above so cutr side on leading .....
 
Years ago I had a oops on diesel fuel and had to replace brake lever. After countless problems of locking brakes I discovered the OEM looking brake lever was out of speck. The lever wasn't opening the return hole fully causing pressure build up after extended rides and locking up front end! Drove me nuts!
 
Once I wore all of the hard chroming off my brake disc, the brakes worked quite a bit better. I still use a stock master cylinder. So I recommend having the hard chrome removed by blanchard grinding or getting a new disc that has not been chromed as one of the improvements.

Peter Joe
 
PeterJoe said:
Once I wore all of the hard chroming off my brake disc, the brakes worked quite a bit better. I still use a stock master cylinder. So I recommend having the hard chrome removed by blanchard grinding or getting a new disc that has not been chromed as one of the improvements.

Peter Joe
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The primary reason the stock Commando disc brake is so poor is the ratio of the caliper piston area to that of the master cylinder piston area. IIRC the stock ratio is around 9:1, whereas, an optimum ratio is ~27:1.

Removing the chrome will improve braking, but not nearly as much as getting a better caliper to master cylinder ratio. Actually, the stock brake needs a smaller master, stainless steel brake line, Ferodo brake pads and removing chrome from the disc. Norton got the disc brake system totally wrong.

I went with the Gremica 11mm master and a Gremica 2 piston 42mm caliper and a floating 11” disc. Ended with a stopper nearly as good as my dual disc Brembo on my BMW.
 
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Ludwig, I was unaware of this modification:
"If you insist on keeping the original caliper , you could cut a step in the pistons over 130 -140 deg. ,like Porsche , Mercedes , Alfa and others did when they where still using fixed 2 piston calipers . ( remove 1 mm from 6 o'clock to 10.30 on leading edge )".

Any idea how this works? Seems like the piston would try to cock in the bore.

Stephen Hill
 
Has any found improvement with a cross drilled stock rotor? These are common on modern bikes. Idea is to give gas venting from under the pads and should reduce disc over heating by giving a little more cooling area.
 
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