1981 GL1100 Rear Master Cylinder Alternatives?


Information and questions on GL1100 Goldwings (1980-1983)
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Banzaibob
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1981 GL1100 Rear Master Cylinder Alternatives?

Post by Banzaibob »



Restoring an '81 GL1100. The rear master cylinder is WAY beyond repair. And as I'm sure you all know, rear master cylinders for the GL1100 are NLA. Does anyone know of a good reliable conversion using an available master cylinder? My guess is that a 14mm master cylinder will push the appropriate amount of fluid. My best guess is also that it is going to require fabricating some sort of bracket or plate with the correct bolt holes and such.

Any ideas? Thanks in advance!


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Rambozo
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Re: 1981 GL1100 Rear Master Cylinder Alternatives?

Post by Rambozo »



grooviebastad
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Re: 1981 GL1100 Rear Master Cylinder Alternatives?

Post by grooviebastad »

Just got into my "new to me" '81 Interstate last week. One of the PO's has swapped the rear master for one off of an '84 GL1200. Capped the outlet to the front right brake ('84 had integrated rear/front right from the rear master).

My father in-law was the last owner. He didn't do the swap, but said it ran and STOPPED great with this setup for years.
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WTF
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Re: 1981 GL1100 Rear Master Cylinder Alternatives?

Post by WTF »

Were there any changes to the front MC?

I wonder if the front MC can push enough fluid to work both calipers if it is plumbed that way?
grooviebastad
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Re: 1981 GL1100 Rear Master Cylinder Alternatives?

Post by grooviebastad »

WTF wrote: Fri Jun 02, 2023 2:14 pm Were there any changes to the front MC?

I wonder if the front MC can push enough fluid to work both calipers if it is plumbed that way?
It's an '81, so it came that way from the factory. Front MC operates both front calipers.
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WTF
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Re: 1981 GL1100 Rear Master Cylinder Alternatives?

Post by WTF »

grooviebastad wrote: Mon Jun 05, 2023 10:15 am It's an '81, so it came that way from the factory. Front MC operates both front calipers.
Ooohhhh...
I wonder what year they came up with the genius idea to plumb them backwards.
I am sure they had rider safety in mind.

I have a buddy that makes hoses for a living, I think I am going to run both fronts off of this one to see if it works.


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