Date: Mon, 17 Jan 94 11:21:19 GMT
From: Bill Dudley
The front brake on the Commando is notoriously high-effort.
My solution was:
1. Turn down rotor to remove chrome plating, exposing much grippier iron.
2. Stainless steel brake line
3. New grippier pucks (I forget whose, but any modern puck is probably better than the 20 year old ones I had in there).
Now I can actually stop the thing quickly with only one hand, and slow it down with two fingers.
Date: Mon, 17 Jan 1994 11:46:59 +0800
From: Daniel M. Milhone
In re: poor disc performance I recently re-did mine, and in addition to Bill Dudley's suggestions (steel line,turn disc,good pads), I included a caliper kit. Well worth the price.
Additionally, the rotor was turned using a different method than the standard lathe type turn job. The exact name of this method escapes me, but it's the same way they turn an automotive flywheel. Kinda circular/swirly pattern. The reason, according to the "expert" was that this will guaranty trueness.
Anyway, mine now works very well, and there is no pulsation due to any warpage.
Date: Mon, 17 Jan 94 15:56:36 EST
From: David B Toepfer
>Steve:
>In re: poor disc performance
>Additionally, the rotor was turned using a different
method than the standard lathe
>type turn job. The exact name of this method
escapes me, but it's the same way they
>turn an automotive flywheel. Kinda circular/swirly
pattern. The reason, according to
>the "expert" was that this will guaranty trueness.
Anyway, mine now works very
>well, and there is no pulsation due to any warpage.
This is called a non-directional finish. It is a required final step to the turning of any friction surface and is also to be put on new steel surfaces that mate with friction surfaces - flywheels, clutch steels, disc rotors. It insures that the friction pads don't follow the lathe grooves out to whatever end it was turned to and jam a pad, let's say, against a surface that would keep it from disengaging properly.
It, also, I think, increases the intiial friction coefficient of the metal.
Date: Mon, 17 Jan 94 17:09:46 EST
From: Scott Lilliott
>Steve:
>In re: poor disc performance
>I recently re-did mine, and in addition to Bill
Dudley's suggestions (steel line,turn
>disc,good pads), I included a caliper kit Well
worth the price. Additionally, the rotor
>was turned using a different method than the
standard lathe type turn job. The exact
>name of this method escapes me, but it's the
same way they turn an automotive
>flywheel. Kinda circular/swirly pattern. The
reason, according to the "expert" was
>that this will guaranty trueness. Anyway, mine
now works very well, and there is no
>pulsation due to any warpage.
I believe the term for the operation is "surface grinding" wherein a grinding wheel passes back and forth over the disk layed flat on a grinding table - Very accurate, more expensive then lathe cut.
Date: Mon, 17 Jan 94 23:06:00 EST
From: David B Toepfer
>>In re: poor disc performance
>>Additionally, the rotor was turned using a
different method than the standard lathe
>>type turn job. The exact name of this method
escapes me, but it's the same way they
>>turn an automotive flywheel. Kinda circular/swirly
pattern. The reason, according to
>>the "expert" was that this will guaranty trueness.
Anyway, mine now works very
>>well, and there is no pulsation due to any
warpage.
>I believe the term for the operation is "surface
grinding" wherein
a grinding wheel
>passes back and forth over the disk layed flat
on a grinding table - Very accurate,
>more expensive then lathe cut.
Actually, it's as cheap as a good piece of emory cloth, and your right (or left, if you prefer) arm. Just start swirlin'
Date: Tue, 18 Jan 1994 08:37:00 -0800 (PST)
From: Stephen Hill
Lots of chatter about turning norton discs. I have found a Norton front end for a project bike I am doing, but it doesn't have a disk.
Anybody have any thoughts on what material would be good for making a front disk?
Stainless? Steel?
I realize it would need to be turned on a lathe. I am mostly wondering about the material and the properties associated with it.
Date: Tue, 18 Jan 94 10:49:16 -0700
From: Andrew Wolf.
If you are crazy enough to make your own disk, I would recommend that you make 2 as I have a friend who needs a Lockheed disc for his 73 750 GT Ducati.
Use cast iron, great in wet weather and generally all around, but they do rust. Not a problem after the mornings first stop. Very powerful
Date: Tue, 18 Jan 94 16:19:26 EST
From: David B Toepfer
The name of the game when concerned with braking materials is, obviously, coefficient of friction. From my understanding of the subject Cast Iron wins out here.
There is, however, a price to pay for the high coefficient of friction; Cast Iron RUSTS. (There's a revelation. Ferrous metals rust. Tell us something we don't know.) Ask a disk-braked Moto Guzzi owner, they can serve as a witness to this fact.
I think the material that most manufacturers (ie Japan Inc.) use is Stainless Steel (Someone please correct me if I am wrong.) It gives little away in the friction coefficient category, and it doesn't rust nearly as easily. Why not retrofit an available rotor from a junk japanese bike you can find? Or is making one yourself that cheap a prospect?
Date: Tue, 18 Jan 94 15:18:19 PST
From: John Kula
After skimming mine, and drilling them, I had them copper-plated. Didn't look too bad, dissipated heat a bit better and proved to be much grabbier.
As for the Boyer, definitely not "stock" or concours --but working brakes were worth it! My two cents worth on the debate: my bike must work well and be reliable, is first priority. Ease of fixing it is a second priority. Concours is a priority for my "collector" machines, but not for my workhorse.
Date: Wed, 19 Jan 94 09:16 EST
From: Bill Dudley
>John Kula writes:
>After skimming mine, and drilling them, I had
them copper-plated. Didn't look too
>bad, dissipated heat better and proved to be
much grabbier.
Don't they turn green (instead of brown) when they "rust" ? Is that better? Does it compliment the British Racing Green paint?
Date: Fri, 25 Mar 94 11:05:29 EST
Had my car brake rotors resurfaced last night
and the beautiful non-directional grinding got me thinking about doing
the same to the Nort. Remember reading about John Kula's copper plated
rotors (still there, John?), and elsewhere about machining off the chrome
plating on the stock disc.
Also mentioned in the INOA Tech Digest is a Norman
Hyde Commando disk kit. Comments?
Date: Mon, 14 Feb 94 10:25:34 GMT
The Rear Brake (drum Type): Be carefull not to
let this bind, it will melt all the grease out of the bearings and melt
the cush drive on the models with them fitted in the rear wheel.
This has happened to me twice.
After re-assembily, I run the bike down the road
a piece and feel the drum, should be cold if you haven't used it. I Have
fitted electrical spi-wrap to the rear brake outer to protect it where
it goes between the 'Z' plate and the swinning arm. Available in Black,
will extend the life of the cable.
From: John Pinkham
From: Peter Aslan