What's the "On-Off" Honda gas cap do?

[TheRadBaron]

Both ATCs that I have are equipped with a gas cap with a rotating lever that goes between "on" and "off" positions. What exactly does the lever do?
It doesn't seem to do anything on either of my trikes.

[swampthang]

It vents the gas tank when in the on position.

[Thorpe]

Off is for transporting, to keep the sloshing, and oozing to a minimum.... (I always leave mine in the "on" position)

[Dirtcrasher]

If the cap doesn't vent (ON), the fuel won't get to the carb. I like vent hoses myself but this was the way Honda did it.....

[TheRadBaron]

Hmm. That's kind of a cool feature. I wondered if it was a venting thing, but I couldn't think of a reason for it. Now that it's been said though, it makes sense to be able to shut off the vent while transporting the trike. I've had fuel slosh all over out of the caps of trailered stuff before.

[honda200x1987]

IMO , like Thorpe said.. for transporting to keep from sloshing out the caps but it could also be good for storage to keep out moisture I would think.

[gus]

Ya moisture and gas tanks don't mix

[atc350xer]

I never turn mine off and they never slosh... guess I need to ride more lol