i'm making some wooden bicycle grips on the lathe...first real turning project. these are going to be very tight friction fitting grips. but, i'm going to be making more in the future and was wondering if i do leave some space for expansion, what might be a good way to fix them to the handlebars?

i see that some company is using these aluminum fasteners with screws to tighten. is this type of fastener sold somewhere and what would you call it? how might it attach to the wood?


also, what finish would you recommend for something like this that will be exposed to the elements occasionally and lots of hand rubbing?