Q
anyone know if there is enough spare (5mm) axle on a factory R500 wheel to fit with spacers in 135mm dropouts?
No, the axle is 138mm like all Shimano road rears. You can easily put a 146mm MTB axle in there though, the axle is £13.99 or less, but you'd be better spending ~£20 on a complete FH-M525 or similar hub as that will get you the longer QR skewer too.
No, the axle is 138mm like all Shimano road rears. You can easily put a 146mm MTB axle in there though, the axle is £13.99 or less, but you'd be better spending ~£20 on a complete FH-M525 or similar hub as that will get you the longer QR skewer too.