• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Motorcycle Indicator Problem

Status
Not open for further replies.

Tekboy

New Member
I have a 1973 Shovelhead Harley, which I have recently restored with new wiring and hand controls.

The left and right turn indicator switches are momentary contact (meaning I have to keep pressing the switch WHILE I am cornering....a major pain.) Each switch has a wire going to a flasher can and a wire going to a dash light.

I have seen a bike similar to mine where the momentary contact switch "triggers" the flashing of the indicators, and a second press turns them off again. I asked how it was done and was told that it involved a proprietary Harley "little box" and $300!

Is it possible to achieve this with common electronic parts. How much techno-savvy does one need to do it?

Any help would be appreciated.
 

user_88

Member
A latching relay might perform the task ....
Something like you see here:
Latching Relay - Deltrol Controls

A momentary pulse from the handlebar switch would activate it.
Press the switch a second time to de-activate it.

Probably contact the manufacturer to select a particular model, and confirm the specifications .... DC 12V .... SP .....Be sure that you have room to mount one for each handlebar. ... Also be sure to observe the relay polarity for DC voltage when you install it. Your local parts store might have something similar.

There are probably other ways to achieve your objective. However this method just requires purchasing the two relays.
 

Tekboy

New Member
A follow Up Question...or two

Interesting. Thanks for the reply. Two questions...

... could I use just one relay and have EITHER switch turn on or off the flasher can?

...how quick do you have to be with the momentary contact switch to prevent resetting the latching relay?
 

MrDEB

Well-Known Member
Another solution

I have a pcboard design that uses a 556 timer that is triggered by the monentary switch.
I sent one to Adown. He hasnt had time to assemble.
If your interested send me a PM for the schematic.
NOTE this is an untried circuit but it works on paper.
 

MrDEB

Well-Known Member
lets see if I get this right??

you right click my name then send private message.
when you log onto the website here then if you have a PM it will indicate you have a PM.
open the messages (top right screen)
please note I suggest breadboarding the circuit first if you are not sure of what you are doing.
the circuit has never been tested.
Adown is assembling a unit to see if it does work.
 

crutschow

Well-Known Member
Most Helpful Member
A latching relay might perform the task ....
Something like you see here:
Latching Relay - Deltrol Controls

A momentary pulse from the handlebar switch would activate it.
Press the switch a second time to de-activate it.
Those relays are not alternate acting, as he wants. They have either one coil, which requires an opposite polarity on the coil to alternate the contacts, or two coils, which requires a pulse to one or the other of the coils.
 

user_88

Member
I'm not clear on the existing layout.

I am guessing that there is a single wire which activates the left turn signal and left dash light .... and also a single wire for the right turn signal and dash light.
You would probably find each of these control wires in the vicinity of the handlebar momentary switches.

So you would need to have a latching relay of some sort for the left and the right sides. ....One separate relay for each side .... two altogether.

If I understand correctly, the flasher can has two different connectors, one for the left side and one for the right side.

Is this correct?
 

Mikebits

Well-Known Member
With a Shovelhead Harley just look mean when turning. Know one would dare hit a mean looking biker :)
 

user_88

Member
If you could draw a wiring diagram or sketch, showing the handlebar switches, the flasher can, and which wires have voltage, wire color, the lights themselves, and anything else useful, it would help to come up with something that would work.

Make one sketch with the existing wiring, and a separate sketch with what you want.

If you don't have a scanner, try the Windows Paint program or something similar, save the sketch as a jpeg file, and post in a message.

It is important to have a good idea of what the parts and layout are before you
try to add something to a circuit.
 

Mikebits

Well-Known Member
Why not just see if there is a manual switch, ie. non momentary, offered by Harley or alternate source. You can't be the first one to dislike this feature.

And what are you doing at a forum on a Friday night? Shouldn't you be out at a biker bar busting chairs over someones head?...J/K
 
Last edited:

Mikebits

Well-Known Member
The bikes that I have owned just had a thumb switch that I would have to flip on, then flip off after I turned. This seems to be most logical to me.
 

MrDEB

Well-Known Member
my circuit will self cancel

only one relay and momentary push buttons on the handle bar.
planning on maybe marketing this unit.
 
Status
Not open for further replies.

EE World Online Articles

Loading
Top