Triumphrat

Readmarx · 04-14-2008

the speedy died on sunday going over a speed bump at walking pace. total electrical shutdown. main fuse blew. put several spares in each one popped. got home and stripped the bike and check connectors, fraying wires, etc - nothing could be found. unplugged the horns, ok... plugged back in the horns - pop! Isololated the horns and a 10amp main fuse doesn't blow. Is this just a symptom of a bad earth somewhere else?

Derswede · 04-19-2008

OK,, if I recall right, the horns are always hot....that it, the "horn button" provides a ground to complete the circuit. In that case, a shorted horn will cause an immediate fuse pop....it is, in fact, shorted directly to ground. One reason I modified mine to use a relay.....Triumph's wiring is not the heaviest in the world and I'd prefer any additional stress (I added Fiamm horns to my Sprint) to be properly controlled. Check the horns with a DVM (ohmmeter) and see if one is shorted.

Derswede

Readmarx · 04-21-2008

one of them is. they were aftermarket items. after rebuilding everything and plugging back in the horn it continually sounds regardless of touching the button or not. I've disconnected the offending item and ordered a couple of new ones to be on the safer side. thanks for the reply.

Buckwheat · 04-21-2008

Forum success!

Derswede · 04-21-2008

Quote:

Originally Posted by Readmarx

one of them is. they were aftermarket items. after rebuilding everything and plugging back in the horn it continually sounds regardless of touching the button or not. I've disconnected the offending item and ordered a couple of new ones to be on the safer side. thanks for the reply.

My pleasure! If you want to isolate that circuit, get a standard horn relay, use the two existing leads for the horn to switch it (connect to the coil leads) and run a fused lead from the battery to the new horns (other side of horn will be grounded) thru the relay contacts. When you hit the "horn" button, it closes the relay and allows current to flow to the horns. If a short occurs, you lose the horn fuse only, not the main fuse. Easy lash-up as well...email if you need more info.

Derswede

Derswede · 04-21-2008

Quote:

Originally Posted by Readmarx

one of them is. they were aftermarket items. after rebuilding everything and plugging back in the horn it continually sounds regardless of touching the button or not. I've disconnected the offending item and ordered a couple of new ones to be on the safer side. thanks for the reply.

Re-reading your comment made me think of something else....the leads to the horn (if like the Sprint) are hot (+12v) and switched...the switched lead is the horn button, which provides the ground path. Maybe there is a short as well in the wiring? Or, one of the horns had an internal short that went to ground (the physical mount ground thru the bracket). If the new horns also sound w/o hitting the button, you've a short in your internal wiring. If one of the existing horns is good, test it on both sides and see if the wiring is OK.

Derswede

Readmarx · 04-21-2008

both horns have been connected to the wiring loom with the proper wiring and connectors and isolated (big piece od plastic separating the two and hanging them off the bike in mid air). horns sound (quite strongly) when the button's pushed. connecting the horns to the frame and turning the ignition on one horn blasts out. change the leads into that horn and that horn still blasts out. I deduce it's that horn or the wiring path to it. I've stripped the wiring as best I can - all the way back under the tank and I can find no fault. I reckon it's the horn.

Derswede · 04-22-2008

Quote:

Originally Posted by Readmarx

both horns have been connected to the wiring loom with the proper wiring and connectors and isolated (big piece od plastic separating the two and hanging them off the bike in mid air). horns sound (quite strongly) when the button's pushed. connecting the horns to the frame and turning the ignition on one horn blasts out. change the leads into that horn and that horn still blasts out. I deduce it's that horn or the wiring path to it. I've stripped the wiring as best I can - all the way back under the tank and I can find no fault. I reckon it's the horn.

The horn that sounds probably has an internal short to ground....if it "bumped" at the wrong moment, it could easily take out the main fuse. Best to trash that horn and get another. The Fiamm "Monster" horn set I bought at a surplus place for $12 work great.....but one of these days I'll get the airhorns installed. "Move it, cager!!"

Derswede

Readmarx · 04-24-2008

ha ha - I worked in Birmingham for a while by the side of a busy main road. There was a large articulated truck that came through each morning at the end of the rush-hour when the traffic was flowing again. The driver had fitted train horns to his rig and used to sound them as he rounded the bend onto the roundabout - it would stop the cages dead in their tracks!

I fitted a pair of Acumen (black) horns and all's good now.

Beep! Beep!