brake light switch

[Guest]

Anything special I need to know about replacing the brake light switch?
I assume there is no need to bleed the brakes after replacing it. Is that correct?

[Yellowbird]

Yes, you're correct. I changed mine last summer. Just unscrew the old one and replace it with the new one. I had the new one close by however, there was only a couple of drops of fluid from the M/C.
I did not bleed the brakes afterwards.

[JohnG]

I have to change mine every year or two as I use DOT 5 which seems to kill them, but I have never needed to bleed afterward.

While I can't say that no air at all gets in, I think it probably gets bled out in the master cylinder during normal use.

John

[Joe Johnston]

Somewhere I have read the "Little Bird" owners have found the switches sold by Harley Davidson dealers are just like those on their 55-57's and is compatable with DOT 5. The switch on my 63SR is still a functioning original and looks similar (NOT identical) to the aftermarket one on my 57. I'm not familiar with the 58-60 Birds, but can't imagine one from HD not functioning on a 58-60. May be worth a trip to the Harley parts counter??

[ncbird]

another option

You could get this one from Ron Francis. This should make your brake lights come on sooner as well. This one is dot compliant and rated for silicone. Grant

http://www.ronfrancis.com/prodinfo.asp?number=SW%2D32

[byersmtrco]

+ 1 on that. I know the rear brake lamp switch for most any early 70's to mid 80's Harley is the same. Example; 1973-1986 FXE SuperGlide.
It's been in mine since the early 90's. I did repl it with a new one when we did the disc brk conv.
I can come up with the Harley part # if you want.

Somewhere I have read the "Little Bird" owners have found the switches sold by Harley Davidson dealers are just like those on their 55-57's and is compatable with DOT 5. The switch on my 63SR is still a functioning original and looks similar (NOT identical) to the aftermarket one on my 57. I'm not familiar with the 58-60 Birds, but can't imagine one from HD not functioning on a 58-60. May be worth a trip to the Harley parts counter??

[JohnG]

I bought 3 of the HD brake light switches for that reason (I use DOT 5 in the TBird and all motorcycles, one of which has a hydaulic switch like the TBird). One died in the usual 1 year period, 2 of them have lasted fine for several years. Not alot of statistical evidence but the fact the HD factory used DOT 5 says they must have made an attempt to take the matter seriously.

John, if you have a part # and an on-line source, that would be good to have recorded as the local guy I got them from has vanished.

[simplyconnected]

I jammed my H-D dealer about his switches, AND I called Harley in Milwaukee. My concern was about buying and using Genuine H-D switches.

Milwaukee said, any of the dealers may use whatever they buy from God knows where. To be more specific, if the dealer can get them from a cheaper (DOT-3) source, he can sell them as long as the switches don't have Harley Davidson's name on them.

Here's the kicker... NONE of them have H-D names or logo's because H-D never made them.

My 1980 FXS still uses the original switch with DOT-5. I bought the bike in Dec of 1979, and waited for the first shipments to arrive in Spring of '80, so I know the history of this bike. From all this, I know there is a difference in switches because Squarebird switches last a very long time on DOT-3, and H-D switches last a very long time on DOT-5.

I no longer use pressure switches in my Fords because they close after you put pressure on the line (and, btw, they fail). My new brake pedal limit switch closes as soon as the pedal comes off the rest, whether I have pressure on the linings or not. (It also freed-up two wires going through the firewall.)

[JohnG]

The 3 I got from the local Harley guy came in bags with the Harley logo. So I am guessing they came from Milwaukee, but only as a stopping point from some parts supplier/subcontractor. They were about $15@ whereas I get DOT3 standard US pieces for about $4.

One of these days I have to take a cutting tool and open a dead one up. I suspect there is a membrane in there that swells due to DOT 5 and becomes inflexible. The composition of the membrane may be the only difference between one switch and another.

[simplyconnected]

John, if the bag said H-D, then you can hold them to the DOT-5 standard. I know... you bring back a switch a year later and say, "This thing failed!" They look at it and laugh because it worked just fine for many hundreds of cycles over the course of a whole year.

These switches don't "snap" in either direction. They have a simple bladder that pushes a contact block towards two posts. With no 'snap' action, the contacts can arc and melt one or both contact posts. Some T-birds use a relay to lighten the load on this switch. That's a good solution.

I'm all in favor of originality, but there's a good reason why NONE of the oem's use this switch. Back in the day, they all used it.

[tbird430]

So what is the HD PN#?

Does it have the same "bullet style" electrical connections as our T-Birds original switches do?

[simplyconnected]

Ok, here's the new story:
The part number is 72023-51D
Detroit Harley wants $19.35/ea.
They told me that the -51D signifies a product change and that they now are compatable with either DOT-3 or DOT-5 as long as you don't change brake fluid types.

<--click here
wants $12.99 (from their catalog).

Oh, these switches have a 1/4" stab connector for the electrical.

[RustyNCa]

Why not just go to Napa and run one that works for $5 and has the same hookup as factory. That is where I found the one I am running.

[60 T-Bird]

Ok...Come on now...I know this is a Squarebird site but we have to post our hogs too...Martin