Functional horn button on quick-release steering wheel

[Mark Worthington]

Hi guys. I posted a few weeks ago about getting a quick release for my 9-bolt Moto Lita wheel. I ended up buying a nice spline-drive, ring-release quick-release hub from Winters performance and it only cost me about $65. A friend with access to a lathe has offered to fabricate an adapter from my wheel to the QR hub, so I am on my way.

I've decided that I want to go with a horn button on the steering wheel, instead of using the Lucas button on the dash as shown on the RF construction manual. I feel that having a horn on the steering wheel is safer than having it on the dash, plus, I plan to use the existing hole in the dash for an engine start button.

So, has anybody used a steering-wheel-mounted horn button along with a quick-release hub? Any photos, ideas or drawings to share?

It looks to me like the Moto Lita wheel is meant to accept a functional horn switch and button somehow. A quick look at Moto Lita's web site suggests that a horn button from a Jaguar or other English sports car might work. Then of course I'll need the GT40 logo on a badge for the horn button, but there have been a few threads on that subject. Any suggestions?

[David Morton]

Mark,
I used a different approach to the problem by putting a Lemo plug in the centre of the quick release and the Steering wheel is the male half of the plug, with the steering shaft as the female half. From there I mounted a 'button' plate behind the steering wheel so now I have the possibility of up to six buttons for anything I choose. The Lemo plug is obviously low current so everything through the plug has relay/solenoid actuation. For the six buttons that I plan to use, they will operate Horn, L.Ind, R.Ind, Flasher, maybe a Mic on/off for Nokia phone via OMP intercomm, and a spare.
The Lemo plugs are easily mounted but their crimping tool is a bit costly.
There are actually more channels/connections in the Lemo plug and one other idea I had was a complete isolation solenoid whenever the steering wheel is disconnected from the steering shaft

Dave M

[DaveWharran]

Mark,
I did a setup similar to I think what David is describing. A little module mounted on the steering wheel where the left hand thumb can actuate the buttons, has a rocker type turn signal button, horn, and headlight dimmer button. The wiring from it goes into the steering wheel hub and to an Amphonol male disconnect. The female is in the steering shaft. A tooth on the male Sweet quick disconnect steering hub is milled off and a setscrew put in the "valley" of the matching female part of the Sweet disconnect. That keys the wheel so it can only be put on in one position....the pins in the Amphonol connector always line up correctly.

The female Amphonol plug wires onto a flexible ribbon cable that runs down the shaft and is formed into a loop around the shaft in a small housing. The loop of ribbon is like a watch spring that allows the steering shaft to turn. A stationary wire exits there to a custom electronics unit I made that contains a PIC chip programmed to recognize the various inputs and turn on/off the proper relays to perform the function of the button pushed. Also on the steering column is an aluminum cam assembly that has two IR sensors on it to provide self canceling of the turn signals. Makes a very neat installation that isn't really noticed unless you're looking for it.
Works great.
Something similar to this should be somewhat easier to do if only 1 wire for the horn is needed.
Dave