FJR Brake Master Cylinder Switch Issue

[craigo]

As to not hijack the clutch FJR switch issue, I thought I would open a new thread and show you all what I have going on. Here are some pics of the switch ohmed out.

Here is a pic of the switch as if the brake lever while braking. Note the meter shows no continuity.



Here is the pic showing the plunger pushed in as if the brake lever was not being applied.



This is opposite of the way it should work. Any help would really be appreciated.

CraigO

[Arnie]

The FJR switch has both NC and NO contact pairs.  You've chosen the wrong pair.
Remember that what you want is the NO set of contacts since the switch is "activated" when the brake is NOT applied.

Arnie

(you've got a fluke brand meter, you should understand above :-)

[craigo]

Arnie,

There are only 2 posts.

CraigO

[ribbert]

CraigO, Are you doing this because it won't work on the bike or just checking it before fitting?

Noel

[craigo]

CraigO, Are you doing this because it won't work on the bike or just checking it before fitting?

Noel

Hi Noel,

I mounted the switch and was surprised to see the brake light on when I walked behind the bike. I switched posts and the same result. Then I thought about what I had done and remembered that it's basically a momentary switch. Only problem is that it's in the off position when I use the brake.

I bought the switch new from Boats.net for the an 06 FJR. It fits the master perfectly but as it's electrical, there was no way to return it. It's been in my desk drawer since I saw the FJR clutch switch post, which is why I brought it up.

Thanks,

CraigO  

[FJmonkey]

Can you open the switch up? Some switches are made to be specific as NO or NC, and others have both. If you get a look inside you can tell.

[craigo]

Can you open the switch up? Some switches are made to be specific as NO or NC, and others have both. If you get a look inside you can tell.

Yeah Mark,

I'm going to open it up tonight and see what's inside. Maybe I can modify it to work as needed. Really, what do I have to loose? Seems odd that I would get the only switch that's F'ed up. And it came in a Yamaha Factory bag and label......

CraigO

[FJmonkey]

Hopefully it has a micro switch inside that has 3 lugs, then you just swap out the offending one and your switch is good again.

[Flynt]

Craigo,

Thinking about this, I think the old switch might bolt on and function the proper way?  It's that or the new one works correctly, I definitely didn't mod that side.

Frank

[craigo]

Thanks for the replies. I just got back from taking the wife out (yeah, on a Tuesday, told you we have a screwy schedule). Looks like I got to park that project till tomorrow sometime.
I'll post a pic if successful or just a pic of the inner workings. I have a feeling that it'll be just swapping out the posts and fixed.

Thanks again,

CraigO

[craigo]

Well I got the switch open and there is no reliable way to modify it. Here's what it looks like inside.



As the FJR master is a 15mm and not the 14mm that makes this work at it's best, I think I will find one and do a proper mod.

Thanks everyone that responded,

CraigO

[SlowOldGuy]

The inside of that switch sure looks a lot like the stock FJ brake switch.  Any chance of reusing the original?

If you want to retain the stock look, consider an FZ1 front brake master cylinder. 

Its brake switch works correctly.

DavidR.

[craigo]

Thanks David,

As you can see from the inner workings, the switch is in the ON position when the brake lever is at rest, causing an open when you grab the brake. Plus, this FJR master was in bad shape when I bought it, requiring a little mod on the plunger. As it's the most important function on the bike, I should just replace it with a good one.

Yep, the FZ1 is on my radar. Quick question, do you recommend a specific year?

CraigO

[SlowOldGuy]

Craig,
I'm about to install a front master from a first gen FZ ('01 - '05) on my '85 to retain the screw-in mirrors.  The first gen years will guarantee you a 14mm master.  At some point after '05 I think Yamaha swapped to a 15mm master cylinder on most of their bikes.

After reading your post, I ohmmed the FZ switch and it works as expected (opposite of yours).  I've been trying to figure out what the circuitry would be for the FJR switch you have and it just doesn't make any sense.  How (or why) do you turn OFF a circuit to make something come ON?

I suppose the switch could providing a signal to the computer which then controls the brake light.  Just doesn't seem like a intuitive design.

DavidR.

[Pat Conlon]

 Something to do with ABS? Other than that, I got nothing....

Like David, I also have FZ1 brake m/c...it is interesting to note that later FJR's also came with 15mm m/c's
15mm is only slightly smaller than the FJ oem 5/8's m/c...the 14mm's work much better.

David, I know in the past you have been leery of grabbing to much front brake. Let us know how you like the feel of the 14mm as compared to what you had..., I like mine much better. Remember..2 fingers!!