How to mount a set of airhorns?

[Lee Davis]

This is how a 1970 Moto Guzzi rider mounted them. And, here is how a 1970 BMW rider did it:






Obviously, the horn fell off the starboard side, leaving a hole. I would drill all my bikes and mount them this way if only Moto Guzzis had that wonderful large case side to work with. OK... here is the question: How should I conceal the holes? Welding and grinding flat would never be able to conceal the fact that it was molested. Perhaps a plug and JB Weld? or even just a rubber plug. I would appreciate some of your thoughts...

[ridingron]

I would locktite and screw a bolt into the hole. A full threaded bolt screwed in up to the head. If you're trying to hide it, good luck.

[rodekyll]

Are the holes in an oil area?

If not, I'd get a soft plug to fit like the big block timing hole plugs.  They'd look like someone had intended it for some access reason.

If they are in an oily area, I'd still use the plugs, but I'd coat the grommet part with some gasketmaker sealant.  I had a similar sealing issue when I added a PCV valve to a Convert timing cover, vertically, beside where the pump casting is.  I only mention that because it's a location above the oil level and not in the same chamber as the thrashing crankshaft.  It's indirectly attacked by oil, mostly mist.  The first time I installed the PCV soft grommet dry, hoping the expansion from the valve insertion would make the seal.  It did not.  Next time I used Permatex "Ultra Gray" gasket maker.  It's been dry since.

So I'd think that if you cleaned up around the hole a good plug would fit well, seal well, not look odd, and the cost of the sealant will exceed the cost of parts (There's your guzzi content).

Don't use RTV there.

[normzone]

Wow, drilled the case to mount a horn?

I wonder what the P.O. would do to mount an attention-getting running light - link it to the rocker arm ?

I would be comfortable following [rodekyll]s advice re anything mechanical - but the imp on my shoulder  says plug that with either the oddest fastener you can find, or possibly something that is obviously an adjustment mechanism of some sort - the odder the better.

[guzzisteve]

Use your imagination, mount a bottle opener. Great for rallies or just out riding w/6 in the trunk.

[rodekyll]

Brad, do you have that pic of the trike's alternator cover handy?  Now That's how you plug a hole!   

[Antietam Classic Cycle]

Obviously, the horn fell off the starboard side, leaving a hole. I would drill all my bikes and mount them this way if only Moto Guzzis had that wonderful large case side to work with. OK... here is the question: How should I conceal the holes? Welding and grinding flat would never be able to conceal the fact that it was molested. Perhaps a plug and JB Weld? or even just a rubber plug. I would appreciate some of your thoughts...

There's a hole there already on Airhead BMWs. Oddly enough it's 6.3 mm/.250".

[Wayne Orwig]

Duct tape.

[RinkRat II]

  Mount them on your helmet, that way the're omnidirectional!

       Paul B

[Sasquatch Jim]

 Tom in Hawaii had  set of horns from a Santa Fe Superchief mounted on his sidecar.
 Maybe he could post them.