The key is for??? Putting gas in?? but what else???
I've tried it in coke machines but no go... Hmmmm

 

I carry two sets - a key and fob on my belt clip and the spare I keep in a small pocket inside my leather jacket. If not wearing my jacket then I drop the second key/fob inside my left front pants pocket.

I also carry a spare battery taped onto the inner lid of my saddle bag that operates the two fobs just in case the battery goes dead on me.

 

Hide-a-key, yep put it right under the lip of your rear fender just outta sight, leave the scoot outside and PM me your address, promise I will take real good care of her!
Sorry, have had a bad case of the smarta$$ all day!
Where ever you decide to ut it if you have security system make sure it goes with you as you walk away from the bike!
Like Arizona's idea of spare fob battery too, but you can also just set your pin code for security so that you can disable if you needed to.

 

inside the gas door since any coke machine key will open it.

 

+1 on the bootlace. It's always with me.

 

If you have a newer bike the key serves no purpose except for locking the forks or the gas cap. Any old barrel key will work in the gas cap and i never lock my forks. Just remember the secret pin to disable the security system and your good to go.

 

I keep a spare in under my timing cover. That way all I have to do is find a allen wrench, which would be easy to do any hardware or a wally world

 

I have never lost my key, but have been 100 miles from home and needed gas. I went to the HD dealer in town and they gave me an old barrel key. I keep it in the glove box in case it happens again.