I have the Magura HC3 15 mm brake HC3 master cylinder (part#2100297) on my bike right now. The lever travel is a little shorter than the OEM but the effort to actuated is much easier and softer. I love my current setup. No regret! The HC3 has 3 WAY LEVER RATIO. The hand activated master cylinder lever has a clever 3 way adjustable point of support (Piston diameter 15 mm = 14 to 16 mm). This mimics the effect of using a piston size 1 mm below and above the selected hydraulic ratio. Simply remove and reposition the lever support retaining bolt for a softer or harder pressure point. All 3 positions offer 90° full radial activation.After using the MC brake for a couple of weeks now I do feel that the lever travel is short with more effort needed compared to OEM. The kit that I ordered came with 18mm bore size for the brake side.
I think I do need the smaller piston size 15mm. Anyone has used that size yet?
Cool thanks man. Got my HC1s in today and came accross this loose in the box. Any idea what it could beYou only need to wire the clutch side micro switch, the brake side is activated by front brake ABS from pressure in the line. Try and see if you can purchase switch wiring adapter from BMW and solder the wires from the micro switch to switch adapter.
Doesn’t this give a more spongie feel when braking ? Or is the 18mm just to hard ? I like a brake which has good feedback but don’t won’t it to be too softThe 15mm piston size for the brake side is perfect, I left my at the 15mm position.
Here is what I did for the micro switch.
I didn't want to cut the OEM plug from the harness so I hacked the female side which is the OEM microswitch.
There is a type of semi-hard WAX that you will need to remove.
Start with a pick and slowly remove whatever you can remove from the two holes.
Then you will need to pry and remove the switch itself.
The switch will break but who cares. All you need is the female connector.
Pry-Remove-Cut until you start to see the connector pins.
Dig around the two pins you need so you have enough metal for soldering.
Cut the surrounding enclosure that has a rectangular shape (you don't need it).
Remove the Micro Switch from Magura master cylinder.
Cut the two wires of Magura switch to the required length.
Solder them to the OEM female plug.
Don't forget to shrink tube each soldered wire.
At the very end you can put a very big shrink tube to cover everything but I used for electrical tape because I don't have a shrink tube that big.
This works very well if you want to save your original wire harness.