New Rotor?

Manu

Manu

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the rotor on my new-to-me sat-for-10-years '72 750 is fairly pitted and might even have a small crack or two. Thinking about getting a new one. I see Andover has stock-looking ones. BCS has Gerling for about the same price. Wondering if one is better the the other or if there are any better sources?

And then there is the cnw/brembo kit for a mere $1400.
Thanks
 
Always replace any doubtfull rotor with a brand new one . Not cheap , but you will be buying full magnetism and no worries about the center working itself loose . When the older type let go it's not pretty .
 
I still run with the original rota but the centre did let go about 40+ years ago had a new centre pressed in and still working today.
 
O.K. , brake rotor .
Good brakes are your life . Other lives too . Replace . Mine came from Walridge Motors , has many holes drilled into it and was not expensive .
 
Manu said:
the rotor on my new-to-me sat-for-10-years '72 750 is fairly pitted and might even have a small crack or two. Thinking about getting a new one. I see Andover has stock-looking ones. BCS has Gerling for about the same price. Wondering if one is better the the other or if there are any better sources?

And then there is the cnw/brembo kit for a mere $1400.
Thanks
Click to expand...
It all depends on how important stopping is for you.

For me, it is everything.
 
Manu said:
the rotor on my new-to-me sat-for-10-years '72 750 is fairly pitted and might even have a small crack or two. Thinking about getting a new one. I see Andover has stock-looking ones. BCS has Gerling for about the same price. Wondering if one is better the the other or if there are any better sources?

And then there is the cnw/brembo kit for a mere $1400.
Thanks
Click to expand...
Or you could fit one of Don Penders kits…
 
ashman said:
I still run with the original rota but the centre did let go about 40+ years ago had a new centre pressed in and still working today.
Click to expand...
Wrong rota.
Dedubyah said:
Might as well go with an RGM 12" disc then, increase braking power and easy enough to make up a new bracket
Click to expand...
When my stock front brakes let me down badly, and at the time the RGM full Grimca front brake system was a cheaper system at the time for me the 12" semi floating disc, Grimca caliper, Grimca MC and SS brake line and longer brake lever that was 15+ years ago for just over $500 at the time, my Norton has good brakes up front now, they all work together and can also be 1 finger operation if you need to, the brake system has worked a treat ever since installing it, so much better than the useless stock front brake and looks so much better as well, great stopping power, the caliper came with a mounting bracket so no need to make one, and it looks good on the bike.

Ashley
New Rotor?
 
that Don Pendor kit at $450 looks pretty good. Especially since it claims to not require other mods. How well does it perform compared to stock?
 
Pender brake works well. I rode with it yesterday. When I first put it on I had issues with one of the pots not releasing.
Don sent a replacement caliper complete directly. It is more brake than most of need.
 
RGM 12" disc, brembo caliper and home made bracket plus 13mm m/c and braided line work a treat. Don't care for the looks of the 320mm disc on the front of a Commando and don't think it would perform better.
 

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Torontonian said:
Always replace any doubtfull rotor with a brand new one . Not cheap , but you will be buying full magnetism and no worries about the center working itself loose . When the older type let go it's not pretty .
Click to expand...
The Commando rotor is a one piece casting. The center does not work itself loose.

As for magnetism... 🧲some hipster buzzword application?
 
Manu said:
the rotor on my new-to-me sat-for-10-years '72 750 is fairly pitted and might even have a small crack or two. Thinking about getting a new one. I see Andover has stock-looking ones. BCS has Gerling for about the same price. Wondering if one is better the the other or if there are any better sources?

And then there is the cnw/brembo kit for a mere $1400.
Thanks
Click to expand...
How about you post some good clear, close-up images of the rotor, and point out the cracks, some pitting, would not be a dealbreaker so long as the overall surface is level.
If you are not interested in cleaning, and thoroughly inspecting, then by all means, get a new rotor, and be glad that they are available. As mentioned, thinking through the big picture, about where you end up with the bike, how much modern breaking that you want on this vintage bike...
 
Manu said:
that Don Pendor kit at $450 looks pretty good. Especially since it claims to not require other mods. How well does it perform compared to stock?
Click to expand...
On fast riding in the mountains I was able to overheat my stock 1975 disc brake. A friend suggested switching to special brake pads sold by Vintage Brake. The fellow at Vintage Brake said these new pads would "transform" the braking on my Commando.
I found that the new pads gave a slight improvement, but I could still fairly easily overheat the brake on long downhill sections with lots of corners, sometimes switchback type.
I fitted the Don Pender brake and that solved the problem. All kinds of braking power now. 6 piston caliper, big friction area, big fairly light rotor. Decent price too.

Glen
 

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