Crusty Master cylinder

[Armand]

I have bought a 1975 r9/6 that was orphaned on a porch for 8 years. I pulled the Mc and it looks like it came off the outside of a submarine. New replacements are $400ish. I see where some folks have moved to a handlebar version and that is pretty spendy. Do you guys have any suggestions? I’ll bite the bullet if needed......Thanks in advance!

[jimmiejag]

Have you investigated the possibility of having your mc sleeved. Here is a link to a company that has been known for decades for quality work: https://whitepost.com/brake-sleeving-re ... -services/
I have known of them but have not used them and they may be expensive, but it wouldn't hurt to contact them and see if they can sleeve your mc and what it might cost.

[Armand]

Jimmie , thanks. I took it off the bike and I am going to take it apart to assess it. I guess that I was just shocked at the price.

[srankin]

Don't despair, the only time you would have to worry about re sleeving or anything like that would be if the cylinder bore is rusted and pitted.
You may be surprised when things are cleaned up they don't look so bad once old fluid and crust are removed.
Then you can get by with a rebuild kit. St.

[willstone]

I've used www.applehydraulics.com They will sleeve and rebuild your /6 MC for $185. The rebuild kits for the 14mm master cylinder are no longer available from BMW dealers. Apple Hydraulics have the ability and parts to rebuild your master cylinder.

[ECJ]

Armand-

There is another recent thread on this topic:

viewtopic.php?f=8&t=16667

Upgrading my 1979 R80/7 to a handlebar mounted MC was one of the single best upgrades I have done for that bike. Braking performance is massively improved. I highly recommend the conversion.

Good luck,

ECJ

[willstone]

Just saw on eBay today (02/06/21) a rebuilt master cylinder for your bike. $199.

[Armand]

Thanks guys. I am in the process of taking it apart now (Sunday). Having some rust trouble. Patience required. I’ll get back w the solution.

[Armand]

Got it apart. The bore is pitted. I see the rebuild kits (when available) are $85+. I figure I’m better off to pay someone to do it right. I’m have a call into Randy long. Thanks gentlemen (and gentlewomen if appropriate)

[Armand]

I sent it off to apple hydraulics (thanks willstone) for rebuild and resleeve. I talked to them and they seemed very knowledgeable and the website is ez to use. We shall see