I thought moving from geared bikes would be simple, but my feeble brain has not been able to figure this out despite several days of reading.

Here's what I want to do:

• Sram Omnium
• 1/8 chain
• WI 16t fw 3/32 (I thought you can use a 1/8 chain on 3/32 but not the other way around) - Also interested in a Halo Clickster or Excess
• Rolf Vigor FX (not flip/flop but website says it can accept a threaded freewheel - shop says it is fixed only and they won't warranty using a fw)
• Sram Rival brakes (Rolf has a machined brake track)

I keep getting conflicting information and the more I read about thread sizes, fw not threading in properly and chain lines the more confused I get as to which products will work together.

Thanks for your help.