Having serviced my Rockshox forks over the years, sometimes I use the crush washers, sometimes I don't. After last time, someone said "Err, they're kind of important". Having just watched the SRAM tech video, there was no mention or sight of them.
On my current Pikes, the damper-side bolt has a flat washer so doesn't seem right to put a crush washer between that and the fork - there were no crush washers in place (from new) when disassembling.
Are they needed or not?
older RS forks have them, newer ones don't. if there were none in there, don't put them in.
IME you can reuse the crush washers maybe once, but good to replace them if you can.
Don't put a crush washer under a flat washer it'll just squish and split. They are supposed to be used with a little metal cup called a retainer. You can buy both for a pound or two. If it leaks from the bolt, you probably need a crush washer, otherwise you can get away without.
OK thanks, I'll just remove them.
