… Do they all go to 120mm with the removal of a spacer? If not, what do I need to look for to make sure I buy the right one?

If its a newer ‘solo air’ model then I think its a little more difficult as you need to replace the air spring (at cost).

No – easier to buy a 120mm if you want 120mm. Are you looking new or second hand?

New solo air needs a spring change. From what I know most dual air’s will but some of the 80/100’s will be OEM and can be different – anything second hand could be different as you don’t know the history. Only way to tell 100% is open them up and see what’s on the air spring.

If you can find new old stock retail version dual airs that should be a pretty safe bet. There was also another thread on here about the same thing a while ago, can’t find it though.

I have done this change with a new fork. It wasn’t that hard to do.

If you phone fisher outdoors and talk to the tech support they can do it for you on a new fork. In my case I wanted a 1.125″ 9mm QR reba 120mm so I had to convert it from a 100mm version.

Are you looking new or second hand?

Either albeit in Vgc. I want to replace the 100 sid RLT on my HT with a Reba or Fox F120 as I’m not racimg it anymore. I’ve got a Swap up in the Wanted section.