Don't want these Ads? Why not sign up as a Trials Central Supporter.

Onemadchef

Brake light wiring problem

5 posts in this topic

I have a 1968 Campera.  How do I wire the brake light switch, as I have a feed wire coming into the switch from the frame then another wire running from brake switch to the resister before heading to the brake light bulb.   If I disconnect the two wires from each other at the brake switch the bike stops running.  If the two wires touch ground the bike stops running?

Share this post


Link to post
Share on other sites

Don't want these Ads? Why not sign up as a Trials Central Supporter.

Perhaps the attachmentScan0003.jpg will help. 

Share this post


Link to post
Share on other sites

The rest of it.

Scan0004.jpg

Share this post


Link to post
Share on other sites

Hi, Does your LT coil have Black wire and a green wire (Earth)? These wires are joined to each end of coil?  You need this type of coil if you want to wire the brake light without using a battery.

Some LT coils only have the Black wire, the other end of the coil is soldered to the laminated core and this is the end where the coil is earthed. It is sometimes possible to unsolder this end of the coil and connect a green wire to it. Better still, find the correct coil.

Assuming all is good...

The black wire from the LT goes to the HT . Cut out button on the handlebars should also connect to this wire

The green (Earth) wire from the LT goes to a connector (A) and from there to the brake light switch .....If your Campera  has the correct switch fitted, it will be closed (Conducts). 

The other end of the switch is connected to the the frame.  The coil is now earthed.. the bike will run.

Run the bike, press the foot brake pedal and the engine stops...(the connection to earth is now broken and the bike won't run.)

Now join another wire from the connector (A) to the brake light bulb. The other side of the bulb is joined to ground. 

Run bike...(Coil is earthed through switch)  Now press brake pedal (Conection to ground is broken) but wait.....a less attractive / slightly higher resistance route to ground through the brake light bulb exists....The bulb lights up and the engine continues running....

But what happens if the bulb blows?....Engine stops.....we need a back up...

Join the wire from the resistor (has a slightly higher resistance than the bulb) to the connector block (A) The other end of the resistor goes to ground. If the brake light bulb fails then your coil will find earth through this component.

This system really does work well. No battery needed...Good luck. :D

 

 

 

 

Share this post


Link to post
Share on other sites

To BultacoSD & HN014!

Thanks so much for your detailed and helpful response to my brake light switch problem.  The weather has turned cold, but I intend to follow your directions ASAP.

Again thanks so much in clearing this problem up.

onemadchef

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now