DIY Brembo Master Cylinder Brake Light Microswitch

DY · 07-11-2010, 12:13 AM

long title so this would be easy to search for.

So I decided to make my own brake light switch because the Brembo MC does not come with one. There are two kits currently available.

One is from Hardracing.com and is around $80 shipped.

Another one is from E-Bay and can be found under "ladybird brake light switch". This one is $50 and comes from Japan. this is essentially what I copied from.

This took me about 50 minutes to make and about $10 of materials. Reason I chose to do this way is because I've heard of some pressure switches don't work very well. This is exactly the same setup as OEM and works the same way.

I'll type up the rest when I work out the details. The prototype is done and i'll try it out for a bit. I just need to order the correct banjo.

here are some pictures. its not very hard to figure out on your own.

**Michcio** · 07-24-2010, 09:17 PM

is it brembo m. cylinder or chinese fake from eBay ??? if thats brembo i wouldn't feel well to do a frankenstein from it. at least you have installed that bracket underneath the pomp.

**Red_Liner740** · 08-03-2010, 12:17 AM

well he hasnt actually done any modification to the Brembo master. he just added a plate to the bottom via the lever bolt...

as long as the plate doesnt rub and scratch the master cylinder, when it removed you shouldnt be able to tell it was ever modified.

DY · 08-04-2010, 07:53 AM

Originally Posted by Michcio

is it brembo m. cylinder or chinese fake from eBay ??? if thats brembo i wouldn't feel well to do a frankenstein from it. at least you have installed that bracket underneath the pomp.

Its a real brembo. its not really modified like Red_Liner said. The only thing I had to do was bore the pivot pin out slightly to fit the screw through.

Originally Posted by Red_Liner740

well he hasnt actually done any modification to the Brembo master. he just added a plate to the bottom via the lever bolt...

as long as the plate doesnt rub and scratch the master cylinder, when it removed you shouldnt be able to tell it was ever modified.

OK, so I've been riding around with this for the past few weeks and its working great. However, I'm still going to change it up a bit.

The problem is that the pivot pin has to be very loose for the lever to return to its fully opened position. If I tightened the bolt all the way, there is enough friction that the lever doesn't return all the way. It is enough to cause pressure buildup. because of this, the switch does tend to move about after a few days of riding and does stop working. All I have to do is push it back in position but this is something I would really not have to worry about.

so for the second prototype, Its gonna have to be held in place not purely by the pressure of the screw. I'm thinking of making a flange that can hook onto a surface that will hold it in place. I will not be modifying the MC at all because it is a brembo.

I'm also installing a small LED on my dash that is linked to the brake light. This way I can be sure of what is going on.

**frekeyguy** · 09-05-2010, 07:45 AM

What i'd suggest is drilling a small hole and using a M3 screw to hold the plate from moving around, I cant really tell how much room is in there.

But brembo does make micro switch kits...

**Red_Liner740** · 09-05-2010, 10:52 AM

Okay looking at the pics i have a solution.

Scrap that piece of alu plate and start new. This time make the plate bigger so it covers the manufacturing date circle stamp. The aluminium there doesnt have anything behind it and is only used for support of the arm. a small hole thats then tapped and threaded to M3 specs (wouldnt go any bigger) and a bolt would stop the plate from rotating.

**JohnnyP636** · 09-17-2010, 01:16 PM

Originally Posted by frekeyguy

What i'd suggest is drilling a small hole and using a M3 screw to hold the plate from moving around, I cant really tell how much room is in there.

But brembo does make micro switch kits...

Brembo does make a micro switch for these masters, but their mounting kit is stupid expensive considering the lever itself is around $250 and just the mounting bracket is $90 + about $15-20 for one of their micro switchs

mount kit
http://www.yoyodyneti.com/ProductInf...oductid=BRP501

The RCS lever you posed is different, it has a mount for the micro switch built into the body of the master. And the micro switch is already included when you buy an RCS

**frekeyguy** · 09-17-2010, 01:20 PM

Originally Posted by JohnnyP636

Brembo does make a micro switch for these masters, but their mounting kit is stupid expensive considering the lever itself is around $250 and just the mounting bracket is $90 + about $15-20 for one of their micro switchs

mount kit
http://www.yoyodyneti.com/ProductInf...oductid=BRP501

The RCS lever you posed is different, it has a mount for the micro switch built into the body of the master. And the micro switch is already included when you buy an RCS

I am not sure why my RCS doesn't have a switch, maybe it was the early version of it. Its currently setup with a pressure switch

its hard for me to imagine right now....but can you use the yoyodyne's mount with the stock switch?

**JohnnyP636** · 09-17-2010, 01:22 PM

Ive installed 2 RCS levers and both came with a switch and banjo bolt in the box, exactly like the picture you posted....Where did you buy yours from? New or used in original Brembo box?

I doubt any stock swithcs will bolt right as most only have 1 mounting bolt and tab to hold it in place. While the Brembo switches use 2 bolts...However Im sure you could figure something out...

Personally I hate the click of a micro switch and prefer pressure switches...