UTT Master Cylinder pressure light

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SteveD
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Re: UTT Master Cylinder pressure light

Post by SteveD » Mon Dec 11, 2017 3:06 am

^^ No cold concrete floors in Sydney ;)
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/
2006 K1200R.

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Zombie Master
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Re: UTT Master Cylinder pressure light

Post by Zombie Master » Mon Dec 11, 2017 3:07 am

Wobbly wrote:
Sun Dec 10, 2017 7:58 pm
Zombie Master wrote:
Sun Dec 03, 2017 5:38 pm
There is no reason to get brake fluid on your paint. That is sloppy work.
You have simply misunderstood. The act of dispersing brake fluid does not require conscious activity by a human. The OP's master cylinder is UNDER the fuel tank where it cannot be observed. When those master cylinders leak, they dribble fluid all over the painted frame and a host of electrical harness connections. Wind (from riding the motorcycle) will then loft the fluid and coat the underside of the fuel tank "tunnel". This condition can exist for months and create quite a mess before the fuel tank is ever removed.

That's the specific conditions under discussion here.

I rode an R90 for 11 years and never had a leak. But then I do silly things, like specificly following the BMW service manual. Safety before cosmetics. :geek:
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Wobbly
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Re: UTT Master Cylinder pressure light

Post by Wobbly » Tue Dec 12, 2017 6:08 pm

Recently went to look at a blue/ silver '83 R100RS on CraigsList with original paint. In the photos it looked excellent. When I got there the paint was completely screwed up on the lower RH fairing panel, inside and outside ! When asked about it he said the handlebar master cylinder had cracked open (frozen ?) and leaked, while the bike was under a cover in the back yard. The brake fluid had eaten all the paint off.

Even with the best intentions "Poop Happens".
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !

robert
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Re: UTT Master Cylinder pressure light

Post by robert » Tue Dec 12, 2017 6:37 pm

Under a cover in the back yard doesn't seem like "best intentions"

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Steve in Golden
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Re: UTT Master Cylinder pressure light

Post by Steve in Golden » Tue Dec 12, 2017 6:40 pm

It should be against the law to put an airhead "under a cover in the back yard." :(

Wobbly
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Re: UTT Master Cylinder pressure light

Post by Wobbly » Fri Dec 15, 2017 10:07 pm

His headlamp bulb was running on 8 volts for sure.
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !

Rob
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Re: UTT Master Cylinder pressure light

Post by Rob » Sat Dec 16, 2017 12:13 am

Wobbly wrote:
Fri Dec 15, 2017 10:07 pm
His headlamp bulb was running on 8 volts for sure.
Is that the one over his head? :idea:
Rob V

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dirtsurfer
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Location: Sydney, Australia

Re: UTT Master Cylinder pressure light

Post by dirtsurfer » Wed Dec 27, 2017 12:59 am

Wobbly wrote:
Sun Dec 10, 2017 7:58 pm
Zombie Master wrote:
Sun Dec 03, 2017 5:38 pm
There is no reason to get brake fluid on your paint. That is sloppy work.
You have simply misunderstood. The act of dispersing brake fluid does not require conscious activity by a human. The OP's master cylinder is UNDER the fuel tank where it cannot be observed. When those master cylinders leak, they dribble fluid all over the painted frame and a host of electrical harness connections. Wind (from riding the motorcycle) will then loft the fluid and coat the underside of the fuel tank "tunnel". This condition can exist for months and create quite a mess before the fuel tank is ever removed.

That's the specific conditions under discussion here.
Well I have removed the tank and found the master cylinder to be leaking onto paintwork on the frame. The underside of the tank looks ok. My local airhead part supplier (4000 kilometers away) has 2 ATE dual disc master cylinder overhaul kits one is listed as pattern.
https://www2.munichmotorcycles.com.au/i ... =2a&page=3
Anyone know what pattern means?

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Zombie Master
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Re: UTT Master Cylinder pressure light

Post by Zombie Master » Wed Dec 27, 2017 1:51 am

Pattern usually means a reproduction in my understanding. I recently went through rebuilding two calipers, and purchased what was claimed to be superior to OEM parts. They didn't fit. It caused me time and money. I ordered the OEM parts, and everything went together without a hitch. I suggest everyone use OEM parts, yes you pay more, but we want to have them available. In the end they are the best deal....IMO
Last edited by Zombie Master on Fri Dec 29, 2017 4:42 am, edited 1 time in total.
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ME 109
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Re: UTT Master Cylinder pressure light

Post by ME 109 » Wed Dec 27, 2017 1:52 am

'Pattern' means aftermarket.
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