Brake discs

[TimClarke]

So all is well with the Strada engine (except for being due a cambelt) and handling wise is good, the only current remaining issue is braking.

The rear disc started binding today and the front ones pulse. There is bright chrome on both discs outer surfaces but rust is evident on both discs inner faces.

I have used disc doctor in the past and he may be able to help although i don't know of the chrome makes that tricky but before i contact him any suggestions as to the best way forward in terms of replacement discs/brake parts go that would be really handy please!

[Steve Brown]

I've used Disc Doctor too for Morini discs and wouldn't hesitate to use him again. The chrome will be ground off of course and if they are left damp they will rust. So long as you don't leave it parked up damp for too long it will be fine. Original discs are very hard to find and most of the alternatives that others have tried involve some compromise or other.
For the rear binding I would first check that the adjustment of the actuator rod is correct, i.e. not pulling on the piston. It needs a little clearance to allow for fluid expansion when hot.

[TimClarke]

I've used Disc Doctor too for Morini discs and wouldn't hesitate to use him again. The chrome will be ground off of course and if they are left damp they will rust. So long as you don't leave it parked up damp for too long it will be fine. Original discs are very hard to find and most of the alternatives that others have tried involve some compromise or other.
For the rear binding I would first check that the adjustment of the actuator rod is correct, i.e. not pulling on the piston. It needs a little clearance to allow for fluid expansion when hot.

Cheers Steve - good advice thanks

[3potjohn]

If the caliper needs attention I recently rebuilt the one on my K1 as it started weeping. Doug at Mdina Italia saved the day.
Sourcing discs on these old crocs is a worry.

[TimClarke]

If the caliper needs attention I recently rebuilt the one on my K1 as it started weeping. Doug at Mdina Italia saved the day.
Sourcing discs on these old crocs is a worry.

Cheers. So far I've just tinkered with the actuator rod and changed the brake fluid and so far it seems OK although the disc is scored too.

The front ones seem to be pulsing less although I've not done anything except ride around a bit. Ive not changed the front fluid as it seems fresh unlike the rear fluid which was old. The braking is not amazing but it's not bad either so I think I'll wait til summers over and see how I feel about it then, but iI don't want to get the discs off to Discdoctor now as I don't want to miss the good weather, that can be a winter project along with a caliper rebuild if necessary. The engine has responded very well to fresh oil petrol and plugs and I've not bothered with the electric start today as it started first kick from cold and when hot too.

[TimClarke]

I've used Disc Doctor too for Morini discs and wouldn't hesitate to use him again. The chrome will be ground off of course and if they are left damp they will rust. So long as you don't leave it parked up damp for too long it will be fine. Original discs are very hard to find and most of the alternatives that others have tried involve some compromise or other.
For the rear binding I would first check that the adjustment of the actuator rod is correct, i.e. not pulling on the piston. It needs a little clearance to allow for fluid expansion when hot.

Excellent tip - the rear brake started binding again and when I checked the brake lever had lost all travel and seemed to be wedged on. I disconnected the actuator and it feed up - I'll experiment with adjustment next it a bit fiddly to get to!

[TimClarke]

I've used Disc Doctor too for Morini discs and wouldn't hesitate to use him again. The chrome will be ground off of course and if they are left damp they will rust. So long as you don't leave it parked up damp for too long it will be fine. Original discs are very hard to find and most of the alternatives that others have tried involve some compromise or other.
For the rear binding I would first check that the adjustment of the actuator rod is correct, i.e. not pulling on the piston. It needs a little clearance to allow for fluid expansion when hot.

Excellent tip - the rear brake started binding again and when I checked the brake lever had lost all travel and seemed to be wedged on. I disconnected the actuator and it feed up - I'll experiment with adjustment next it a bit fiddly to get to!

Thanks again for this tip - brakes all good now! Starts first kick, rides beautifully - Excellent!

[Steve Brown]

Glad it's sorted. You should try a 350 next-then you'll see what Morinis are all about!

[TimClarke]

Glad it's sorted. You should try a 350 next-then you'll see what Morinis are all about!

I'll keep my eye out for a good one!

[Steve Brown]

I know where there is one! I'm sure other members will back me up on that. All the other secondhand bikes out there can't tell you where they've been for the last 40 odd years and what's happened to them. Mine can.

[TimClarke]

Update on brakes - the rear disc is sorted, it looks like it could do with a skim but it works as well as i want a rear brake to work and there's no binding any more.

Front discs do need sorting though in that they seem reasonably powerful and smooth about about 30 but between 30 and 5 pulsing gets progressively worse accompanied by some mildish brake judder which i don't like.

Any ideas worth trying or is it time to grind off the chrome, which is patchy on the insides of the discs?

[Galligaskins]

I had a similar issue on the bike I bought last year. There was a dark print of the brake pad on the inside face of the disc and a consequent pulsing of the brake at low speed. Particularly annoying when trying to come to a smooth halt.
Colour me nasty but I introduced the brake disc to my random orbital sander with some 60 grit. The chrome on the disc is incredibly hard so no concerns about taking too much material off, but with a bit of effort I managed to remove the imprint making sure to address the whole surface to keep it consistent.
That's fixed it. Initially, the braking power wasn't as good as previous but as the disc surface polished up again and bedded in over just a few miles it's back to the same power as before minus the judder.

[TimClarke]

I had a similar issue on the bike I bought last year. There was a dark print of the brake pad on the inside face of the disc and a consequent pulsing of the brake at low speed. Particularly annoying when trying to come to a smooth halt.
Colour me nasty but I introduced the brake disc to my random orbital sander with some 60 grit. The chrome on the disc is incredibly hard so no concerns about taking too much material off, but with a bit of effort I managed to remove the imprint making sure to address the whole surface to keep it consistent.
That's fixed it. Initially, the braking power wasn't as good as previous but as the disc surface polished up again and bedded in over just a few miles it's back to the same power as before minus the judder.

That's really interesting - i'll have a good look

[TimClarke]

They don't look to bad on the outside, but the insides are very patchy

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[TimClarke]

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