Front master cylinder brake light switch: Is there an alternative?

[LeRoy]

I just ordered a replacement brake light switch for the front master cylinder on my 1986 Le Mans 1000. I'm pleased to say that Harper's had one in stock and at an agreeable price <tip of the hat>. It's on the way to me, probably as we speak.

The part number in question is 28741100 and I believe it was installed on a range of Guzzi models in the mid-'80s; Le Mans IV, SP II and V65 Lario among others. It may be specific to the weird trapezoidal master cylinder those bikes used.

Now here's the rub: It's apparently a discontinued part. Most of the suppliers I checked had none, or just one, in stock. Back-order times are lengthy. Does anyone know if there is an alternative part available? As I said, I'm pleased that Harper's had one in stock and my current needs are met. But since the first one only lasted 30 years, you never know when you'll need another and I'd rather have one on the shelf if they are truly discontinued?NLA.

[Antietam Classic Cycle]

This one?



Used on a bunch of older Euro machines. Aermacchi and MZ are two I know of for sure. Apparently made by/for Magura.

Alternatively, a pressure type switch could be used instead of a banjo bolt in the brake system.

[pressureangle]

Just installed this in my '74 Aermacchi-Davidson. High quality part, works great. Can't say whether it's exactly the same as Guzzi.

http://www.ebay.com/itm/120631323636?item=120631323636&viewitem=&vxp=mtr

[Old Jock]

I have a pressure switch on my LM 1000  instead of the unreliable Heath Robinson piece of junk micro switch

They work great and are reliable and its what is going on the 1100 build too

The only downside, they are pressure switches, from my experience they operate a fraction of a second later than a micro switch but we are talking single digit milli seconds.

Some may be uncomfortable with that, but I'd rather have something that works every time and I can count on

The back brake on a lot of Guzzis is pressure switch operated anyway

John

[Triple Jim]

A pressure switch needs a small amount of fluid flow into it to actuate, so some users claim to notice a slight bit of mushiness added to the lever feel.  I've never done a side by side test to prove or disprove this.