The BSA A7-A10 Forum

Technical => Lucas, Electrical, Ignition => Topic started by: Andreas Larsen on 07.03. 2014 07:43

Title: Front brake light switch
Post by: Andreas Larsen on 07.03. 2014 07:43
Hello guys!

I was wondering if it's worth fitting a switch for the brake lights on the front brake? And if anyone might have any experience with sneaky ways of doing this? I'd prefer to avoid cutting cables since I have no experience with this.
A friend of mine recommended a so called micro switch, but I'm at a bit of a loss as to where to mount it and still keep it elegant.

Thanks for input.

Andreas
Title: Re: Front brake light switch
Post by: bsa-bill on 07.03. 2014 09:22
I bought a cable with switch already fitted, didn't use it but obviously they are available
Later found out it was for later TLS brake, might be worth contacting (Turners I think) who make up cables to order or if your not too bothered about originality look for a japanese lever with switch combined or a mercury switch if such things still exist
Title: Re: Front brake light switch
Post by: Greybeard on 07.03. 2014 09:55
I've been wondering about using a reed relay. These consist of a short glass torpedo about 2mm in diameter and 10mm in length with a contact protruding at each end; the contacts are pulled together by an external magnet. A thin magnet could be glued to the underside of the brake lever, the reed relay to be mounted below the magnet. The advantage to this idea is that water could not cause mischief to the contacts. You'd need to make sure the contacts can handle the current; if not, might need to hide a conventional relay somewhere to switch the brake light supply. An advantage to having a secondary relay is that very light wiring that is easier to hide could be used for the reed.

Some pictures here: http://www.meder.co.uk/reed-switches3.html
Title: Re: Front brake light switch
Post by: lawnmowerman on 07.03. 2014 11:39
Hi Andreas

Goffy has the switches here http://www.norbsa02.freeuk.com/goffylighting.htm It would mean removing a section of the cable outer in order to fit.

Jim

Title: Re: Front brake light switch
Post by: muskrat on 09.03. 2014 02:33
G'day Andreas.
Here's a pic of the micro switch I have on my cafe. I don't know if it could be done like this on standard levers.
Cheers
Title: Re: Front brake light switch
Post by: duTch on 09.03. 2014 05:45

 That looks pretty neat Musky, where'd you get that from...??

 This thread is opportune, and reminding me of some discussion in a thread a while back, of which, due to my input Graybeards' words have haunted me- (if it's fitted it should work.....!),re;-
 I have a conical front wheel with the matching switch block/brake lever, (well it's a Fonda wHour/magura lever, but don't tell anyone).
  It has the integrated brake light switch which is connected, but it only works for a short time after I tend it- I suspect the plastic in the switch can't cope with the amperage (21W @ 6v=3.5A...?),- was thinking that relay idea that Graybeard put up may work, but a 6V relay is so far elusive- do they exist *????*

 Other option is just connect it to the cable switch same as what Bill had, but it just seems too after-thought-ish/tacked on, and cluttery

  cheers *beer*

Title: Re: Front brake light switch
Post by: muskrat on 09.03. 2014 06:44
G'day duTch, got the switch from Jcar or Tandy, about $5. Works great and whith the lever down in the normal pos it's unseen. I had a look and it can be done to the standard steel levers.
Cheers
Title: Re: Front brake light switch
Post by: Greybeard on 09.03. 2014 08:45
A Google search shows 6v relays
Title: Re: Front brake light switch
Post by: duTch on 09.03. 2014 08:53

 Thanks guys- now I have two less excuses... *good3*
Title: Re: Front brake light switch
Post by: Andreas Larsen on 10.03. 2014 08:49
Thanks for all the great input guys! :)

Gonna have a look at it soon.. But I've run into some new issues that I will have to sort out before getting into the brake light - Since converting to 12V the electrical has been acting up.. I think I have a bad frame connection somewhere since the fuse breaks every time I turn on the lights.. if I keep the switch off and apply the back brake the light turns on with no problem.. I might just replace the entire system since I think it's still the original wiring on most of the system..

Also I had a run  a couple days back, and i was cruising at around 35-40 mph I think in 3d.. and suddenly the engine coughed and died on me.. first I thought I'd run out of petrol but there was plenty.. opened and closed the lever a few times, kicked it once and it started right up again... After about another 10 miles same thing happened again at around 35 mph.. I tried opening the reserve lever to see if it was the main one that was bad but it still died on me.. May be the carb? or timing? I've been having trouble getting it started from cold as well.. not sure if it's related or just me being rusty using the kickstarter..

/A
Title: Re: Front brake light switch
Post by: Greybeard on 10.03. 2014 09:33
My new wiring harness had earth return wires so taking the frame out of the equation.

I'd suspect dirt in the jets for the engine problem. Did you try dropping the choke and applying full throttle? This can sometimes clear the jets.
Title: Re: Front brake light switch
Post by: Andreas Larsen on 10.03. 2014 09:51
Ah awesome! I'll keep that in mind when doing the new harness - Luckily I have a good friend that's good with car electrics, so I'll see if i can't get him to give me a hand.

It hasn't got a choke lever, but I'll try giving it some throttle and see if it clears the jets, otherwise I'll have to take it off and clean it.
Title: Re: Front brake light switch
Post by: orabanda on 10.03. 2014 15:52
I have commenced installing a brake switch in the front cable of all my bikes, as per late 60's Triumphs and BSA's.

I buy my switch from Venhills, altough they are available from others as well.

http://www.venhill.co.uk/Controls_and_Levers/MOTORCYCLE_CONTROLS/SWITCHES/T_0462-P_IN_LINE_STOP_SWITCH_LESS_CAP_&_COVER.html


The venhills version has an excellent rubber boot assembly (sold as a separate part no), which seals the terminals nicely. It is listed as an accessory to the switch (see web page above).

To install, just buy about 1 metre of twin core wire from your local auto accessories shop (cost me about $4), and connect in parallel into the two rear brake wires (where the switch wires enter the wiring loom).

The light comes on when the brake is lightly applied.

De- light- ful!

Title: Re: Front brake light switch
Post by: Topdad on 10.03. 2014 16:27
Andreas, I'd also check your tank for crap ,especially if you find the carb filter blocked ,good hunting BobH
Title: Re: Front brake light switch
Post by: Greybeard on 10.03. 2014 16:49
It hasn't got a choke lever, but I'll try giving it some throttle and see if it clears the jets, otherwise I'll have to take it off and clean it.

Perhaps you can slap your hand over the intake while revving up. Obviously don't do this while riding the bike  *smile*
As Topdad says, the muck is coming from somewhere so cleaning out the tank and tap filters as well as the carb is a good idea.
Title: Re: Front brake light switch
Post by: bsa-bill on 10.03. 2014 17:08
I said
Quote
might be worth contacting (Turners I think)
but Richard said
Quote
I buy my switch from Venhills

And now I think it was Venhills but also some interesting stuff coming out of this electronic and so forth, all to fool folks into thinking we have brakes ;)
Title: Re: Front brake light switch
Post by: kiwipom on 10.03. 2014 21:04
hi guys, I was thinking of this problem and wondered if a `Mercury switch 'would be useful. On searching for Mercury switches I found this..... looks like it`s been done what do others think,cheers

My motorcycle, has a lot of engine braking, so I'm often slowing down just on throttle without touching the brakes. That means I'm open to getting rear ended by an in-attentive driver. Conventional wisdom is to touch the brake pedal when doing this, but it's easy to forget to do that.
I installed this with one wire to the battery +ve, and the other tapped into the normal brake light power wire, near the brake light. I stuck the sensor on the top of my rear mudguard, under the pillion seat, at a rough 25 degree angle.
Now my brake light comes on whenever I slow am slowing down, whether or not am using the brakes.
   
Title: Re: Front brake light switch
Post by: bsa-bill on 10.03. 2014 21:19
Quote
I found this..... l
  - what would that be then  *smile*

Way back early sixties my uncle  had an AJS that had a mercury switch fitted, simple but effective little device, although descending steep hills ?????
I wondered if such things would have fallen foul of elfin saftey