TECH request: Can you ID these spark plug covers..??

[ESnacky6]

My buddy John scored a pair of these suckers...
They look super neat-o... are they motorcycle only..??
what era..?? ever seen them on cars/trucks..??
ANY information would be greatly appreciated..!! Thanks..!!!

[ESnacky6]

#2...

[ESnacky6]

on a panhead...

they would look so neat on a car/truck engine too..!!!

[BigJim394]

I have similar design Bosch spark plug covers for a 1973 Laverda motorcycle I own (I got them in a box of parts with the bike, and it's what they originally came with). Most Laverda experts suggested not using them,other than on a concours type restoration, as the metal shielding eventually gets some arcing from the voltage going through the plug, no matter how good the internal insulation, and that it usually starts slowly so that the way it starts to screw up how the engine is firing/running, isn't that noticeable at first.


They are cool and different looking, though.

[ESnacky6]

bttt

[RF]

Schuler's a fag...tell 'em to just give those to me, along with his XLCH nacelle!

[ESnacky6]

Rob, I didn't know that about him...
we don't have 'that kind' of a relationship...Hahaha..!!

I'm just bummed he isn't coming up for Turlock..!!
oh well, I'll be down for the Big 3 in a month...
Later...