Bought rear wheel kit, & then 2nd hand bike @ charity shop. This 1 has derailleur fixed to axle, so not right when kit wheel fitted, as flats on its axle makes derailleur to be @ wrong angle. Bought +1 bike from auto salvage, this better derailleur as fixed to frame, & has front disc break & rear suspension. Kit's wheel @ 26" = bigger than what would've been on rear, so normal breaks in wrong place, but as kit includes disc break, 1 may use that, now found that axle mount + it = too big! so pads hardly touch the disc, (on phone they say they can re-drill mount to = right), but there be mount on frame for it, but as the wheel = too wide, this also not right. So needing to cut spacer, but then also remove some gear cogs from other side so wheel still centred.