Author Topic: Brake hoses K75s non ABS  (Read 2639 times)

Offline Andymcg

  • Curious
  • Posts: 3
Brake hoses K75s non ABS
« on: November 17, 2020, 09:19:28 PM »
A late night thought.
On my R100R the flexible, stainless braided, hydraulic brake hose goes direct to one Calliper, which is connected to other side by a rigid metal pipe. I have seen people convert this to having two flexible hoses, one to each calliper.

My non-Abs K75 has a splitter on the top yoke and flexible pipes ( original 1987 rubber) to each side, but not all way to calliper: there is a short metal pipe the last 100mm or so. Does anyone know if it is possible to run a longer flexible hose direct to callipers? Having fewer joints could be a good thing. The fittings on the metal pipe have, superficial corrosion so it would look smarter if all new.
Has anyone done this modification?
Would it work and can you see any problems?
  • Northumberland. UK
  • 1987 K75S

Offline Laitch

  • Faster than a speeding pullet
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Re: Brake hoses K75s non ABS
« Reply #1 on: November 17, 2020, 09:39:31 PM »
BMW abandoned your current set up in 1991 for the right hose/bridge pipe arrangement—less parts so less cost, faster assembly, perhaps more efficient braking.

You might take a close look at what could happen with flexible hose running full length at the splitter when the forks are extended, compressed and turned to lock.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline The Mighty Gryphon

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Re: Brake hoses K75s non ABS
« Reply #2 on: November 17, 2020, 09:49:38 PM »
I would guess that the original configuration on your bike was designed to minimize the amount of rubber flex line in the system to minimize the amount of sponginess caused by the flex hose expanding under pressure. 

If I was replacing the flex lines on your bike, I would look at whether or not it makes sense to upgrade to the newer configuration with the hard crossover tube between the calipers.  Together with braided stainless brake lines that will give you the most positive brake feel.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Chaos

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Re: Brake hoses K75s non ABS
« Reply #3 on: November 17, 2020, 10:01:55 PM »
Keep the current setup, spruce up the pipes a little and get some SS brake lines.  simple mods sometimeshave a way of coming back to haunt you.
  • sw ohio
1987 K75S    VIN 0231
Original owner, Original litter
200,000 miles (plus or minus) and 5 paint jobs
sold 6/23
2023 Ural 2WD sidecar (BMW's bastard step child)

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