vulcan bb

boydmtbrider

hi my sons vulcans bb is shot and needs replacing does anyone know what size is needed?can it be upgraded to something better? would the grankset need replacing to?

supersonic

What year/model of vulcan?

Neal_

If it's the red one then it's a square taper 68x113 and pretty much the best you can get is a Shimano UN54 or UN55 (identical apart from the UN55 has a metal locking cup rather than plastic). If you're unsure exactly what BB you need just take out the existing one and see what's written out it.