How do I clean/restore white hand grips.

[Ed Stately]

I have a bunch of white hand grips, I'm assuming a few different materials, definitely different ages that are at best, dirty and at worse stained and a few that seem to have lost or are losing their elasticity. I'm looking for suggestions on how to brighten them back up. Thanks.

These are a few showing what I'm up against.

 

[rickpaulos]

Orange based hand cleaner and your hands works pretty good. I use Fast Orange for hands and grips and any number of bike parts.