Cast iron replacement discs, '82 airhead
 

As my front discs are badly grooved I've ordered a pair of cast iron replacements from Moto Works. Am I doing right?

They can't be any worse than the stainless originals (not as pretty and shiny, true.) I'm getting Ferodo FDB108P pads to go with them. Actually, they did offer newer, more expensive, pads to go with them but since I've ridden the last 100,000-plus miles on crap brakes I do have reservations about braking too hard banked over (come on, most of us do it) and doing a whoopsie before I'm used to brakes that really work.

John

I've got the PFM cast iron disc (also goodrich braided hose)on my R80ST, originally had the Ferodo pads fitted, but now using the EBC HH pads, a slight improvement.

Hi, fatal.

Thanks for that. Yes, mine are (will be) PFM too, but I didn't go for the Goodrich hoses, as all of a sudden time has all gone (what- AGAIN???) and all my plans for making up both hoses and pipes have been dumped and I've just gone and got myself a set of BMW hoses again.

Tell me, how do the discs work- you are happy with them, yes?

John

PS Have just re-read your reply. You said 'slight improvement,' I took it you meant the PADS were a slight improvement, but perhaps what you were saying was that the disc and pad combination were an improvement. Sorry, I see what you mean. Thanks again.
J

[This message has been edited by John Roberts (edited 11 February 2005).]

...Hey guys, if you haven't already, read this thread:http://www.stoptech.com/whitepapers/...otors_myth.htm
This has some useful info on breaking in new pads and rotors. It applies to motorcycles as well as cars. This ling is in the bike-tech section to the left.
Good luck!

YES!
I've been using MW cast iron discs for over a decade on all my bikes. Fully floating of cause.

How has they worked for you since your posting in 2005 ?

Sorry, it took a little while for me to see your reply, I'm a lot happier with them, but recently they seem to bind on one part of one of the discs, a thin layer of corrosion seems to have spread from the outer edge of the disc to the actual braking surface, as it's on the inner face of the disc it's rather difficult to clean/scrape off. It is shiny and black in appearance and it's essential to clean it off completely without leaving an edge which would chew up the pads with every turn of the wheel.

I would be very interested to know if anyone else has had this problem with cast discs. Someone suggested applying the brakes very hard ocasionally, well, they get applied hard on a regular basis anyway.

As things are I haven't ridden the bike much in the past few weeks as I've had an operation including a skin graft on the palm of my hand for Dupuytren's Contracture so no more biking for a few more weeks by the look of things. :( I'll write an update as and when.

PS, I've just noticed you said yours are fully floating and that in your profile you have an R/RT, is that an airhead? If so how did you manage to fit them?

Hi John, depending on what you are willing to spend, I can let you know on the brake set up i have fitted to my GS, I fitted a cast iron pfm but spent money on a Harrison Billet 6 pot mini brake for the front. The Harrison 6 pot really makes a huge difference and will haul the gs 2 up fully loaded down in total control in wet or dry. Its only problem is it does need regular cleaning or you can get uneven wear and drag on the pads. Replacement pads are also pretty expensive.
I also fitted a HPN rear drum brake conversion again expensive - this gives different brake shoes (different shape and material, and a different cam which means the back brake works. I mean really works well almost as good as a modern disc set up (well nearly as good with some imagination). But together the two brakes work excellent and are well up to modern bike standards.
seems the saying yer pays yer money and .........
is right in this instance.
tchus.

Hi, Brian,

Thanks for that, but I have to remember that it's an R100RS that I have after all, and of pretty modest performance compared to modern bikes, alas. Having said that, though, your set-up does sound very interesting, perhaps you could post us a picture if you have one handy?

The reason I was asking about dc lindberg's fully-floating set up was that I was interested in the engineering aspect, how it all fitted on R100RT (if that is what he has) forks and hubs.

Hwyl fawr!

Hi John,

Am unable to upload pics... "your quota is full"...

MW's cast discs, fully floating, is strickly bolt on. One detaches the old once, send them back for a generous "refound" and bolt on the -new- fully floating.

Stock brembo calipers are used but can of cause be swapped for better or worse calipers.

There are German options with s/s discs.
I prefer the cast iron since these are as good (or bad...) in all kinds of weather; so one does not encounter surprices due to sudden rain or dryness, sleat or snow.

I have these discs on my 1984 R80/7, 1982 R100/RS-RT, and will have such also on my R100RT 1981.
Fits all with cast iron R75 and on.