74 R90 – bar mounted master cylinder – how to

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Airbear
Posts: 2886
Joined: Tue Aug 03, 2010 10:02 am
Location: Oz, lower right hand side, in a bit, just over the lumpy part.

74 R90 – bar mounted master cylinder – how to

Post by Airbear »

Results are in. I’ve just been for first rides with a Magura bar mounted MC driving my ATE single disk. Braking is significantly improved over the under-tank MC – at least 25% better braking, I reckon.

Nice thing is that the Magura costs about half the price of the refurb kit for the original MC (in Oz it is $190!!). And it looks like it’s meant to be there.
Here is the final result …

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And here is a link to a thread on ADV that inspired the project

http://www.advrider.com/forums/showthread.php?t=742109

The Magura MC is a 13mm Series 225. Cost: US$87, from Amazon. There are other suppliers. A suitable brake light switch costs an additional $13.

http://www.amazon.com/Magura-Hydraulic- ... B001J8MSDE

Here’s how I went about it -
The mod is particularly suited to the 74 model with the /5 switch gear. My bike has the euro bars, which are a little narrow, so I lathed up some handlebar extensions. These add an extra 25mm each side, and are drilled and tapped for bar-end mirrors.

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So, just hack off the brake lever part …

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Bog and paint. I used thickened epoxy.

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I had a local bloke make up a ss brake line – cost: $70.

Here's how the MC and throttle fit on the bars. The MC clamp is very close to the bend in the bar - thus the need for the extensions.

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The verdict: Highly recommended. I am delighted with the result. I did have the old MC working well, using all the usual tricks. It was adequate for solo riding most of the time, but with a load or a passenger its shortcomings led to far too many arse-puckering close calls with cars and critters. Then there was the problem of the old one leaking and dribbling brake fluid all over the frame. This had obviously happened many times on mine over the decades, with resulting nasty rust pitting.

(Edited to add: I've just been for a decent ride and tested the brake further. The pads are now bedded in properly and I'm thinking that the braking performance is more like a 100% improvement. The difference is frankly astonishing!)
Last edited by Airbear on Wed Oct 10, 2012 1:06 am, edited 1 time in total.
Charlie
and Brunhilde - 1974 R90/6
Image

Graduate, Wallace and Gromit School of Engineering and Design (Pending)
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dougie
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Joined: Wed Aug 04, 2010 6:19 pm
Location: Burlington Ontario, Canada

Re: 74 R90 – bar mounted master cylinder – how to

Post by dougie »

NICE!
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
ME 109
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Joined: Tue Aug 03, 2010 3:00 am
Location: Albury, Australia

Re: 74 R90 – bar mounted master cylinder – how to

Post by ME 109 »

You've been very busy Charlie, Brunnies looking great!
New tank rounders too, woo hoo.
Man, she's. gonna look great covered in mud at the next Alpine. :mrgreen:
Lord of the Bings
Major Softie
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Re: 74 R90 – bar mounted master cylinder – how to

Post by Major Softie »

Lovely!
MS - out
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SteveD
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Joined: Tue Aug 03, 2010 3:29 am
Location: Melbourne, Oz.

Re: 74 R90 – bar mounted master cylinder – how to

Post by SteveD »

Looks great Charlie...well done. What else have you done to the bike? Matt black paint, new brake mc, ....
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Garnet
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Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Re: 74 R90 – bar mounted master cylinder – how to

Post by Garnet »

Wow Charlie. Nice job.

Brunhilde is looking quite dapper. She must be feeling very pumped. 8-)
Garnet

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Major Softie
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Joined: Tue Aug 03, 2010 1:46 pm

Re: 74 R90 – bar mounted master cylinder – how to

Post by Major Softie »

SteveD wrote:Looks great Charlie...well done. What else have you done to the bike? Matt black paint, new brake mc, ....
LED auxiliary lights

Custom headlight nacelle ears.

And that's just the stuff we can SEE.
MS - out
chasbmw
Posts: 765
Joined: Fri Aug 06, 2010 7:40 am
Location: Bath UK

Re: 74 R90 – bar mounted master cylinder – how to

Post by chasbmw »

Looks very nice
Charles
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Replica 1070 R90/S (based on 82 RT)
1975 R90/6
Mal S7
Posts: 661
Joined: Thu Aug 05, 2010 5:26 am

Re: 74 R90 – bar mounted master cylinder – how to

Post by Mal S7 »

Lookin good Charlie. New Brun. The lick of make-up won't hide her character.

Your brake conversion is a bloody bargain! Cost me about 5 x that a dozen years ago for mine.
Still probably the best modification I have made.

Next trick is the twin-disc set-up .... maybe a week off over xmas will mean I have some time.

cheers
mal
Jean
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Joined: Wed Aug 18, 2010 7:43 am

Re: 74 R90 – bar mounted master cylinder – how to

Post by Jean »

Airbear, HOW did you fasten the extensions into your handlebars? Are they an interference fit...epoxy, or what?
Clemson, SC
R100s, R75/5
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