Cost less than three bucks at walmart, small masterlock combination lock. Enough to keep someone from casually picking up your helmet and walking away.

 

thats a great idea...i hate leaving my helmet on my bike when i go places..i also hate carrying it around lol

 

That is a good idea!

 

i hang my helmet on my mirror and use a small master lock to connect it to my clutch or brake cable

 

I use an inexpensive bicycle cable lock and lock it through the triple or wrapped around both sides of the risers now that I have a ride with a nacelle. Added bonus - covers the fork lock on my ride, and provides a hindrance to anyone steering should a thief come 'round. Works best with full face helmets, mind.

 

thumbcuffs, got the idea from a guy in the sportster section.
around mirror stalk and helmet loop

 

I just use one of those free rope-like gun locks that some people give away.

 

I like the idea. I just wish we didn't have to worry about someone stealing but I am dreaming of course, lol

 

Way way back in high school I put a combination lock on my car's hood to prevent theft of my goodies underneath it. Then I had a engine fire and... well... it's hard to calmly open a combination lock under duress.

I don't use combination locks anymore.

On the other hand, I have been able to open many cheap combination locks with just a little pressure on the lock and a feel for when the "notches" seemed to line up. Not that anyone would go through that trouble for a helmet, but a keyed lock is just easier to use in most circumstances.

 

+1 thumb cuffs