my Rap C has ribbed front drums and aluminium brake plates (BS type?), and to be honest they don't brake as well as "claimed"nor as I had hoped.
compared to the (Indian) Royal Enfield Bullet brake plates they share the same (forgive my wording) flaw: there is little to no real support on the pins. this is demonstrated when the nuts are loosened and the pins can be literally pushed back and fro; more in the direction of wheel rotation than opposite.
on one of the brake plates, with the nut undone and dial gauge touching it, it has deflection of 0 against rotation and a whopping 1mm in the direction of wheel rotation. 2 items are jointly responsible for this:
1- the pin(s) resting only on the hex flange (which is small, 15mm across the flats and 17 at the corners)
2- the hole in the brake plate is oval, and gets more oval with the braking experience it gains.
result are brake shoes that do not run square with the drum, holes get more oval and braking efficiency drops. not taking into account the flexing of the brake plates themselves.
anybody tackled this without getting replacement drums or fitting 2LS brake plates?
made a dummy pin with round 20mm flange and that already drops the movement from 1mm to just under 0.4mm (without any nut pulling it). pondering on reaming the holes from 9.51mm (⅜") to 10mm then fit new oversize pins with slight interference fit and larger flange (26mm) and filing a flat so that 2 pins adjacent each have the flats touching to act as a stopper when tightening the outside nuts.
what are your thoughts on this? again: NOT replacement 2LS stuff (with all respect to those that made them).
compared to the (Indian) Royal Enfield Bullet brake plates they share the same (forgive my wording) flaw: there is little to no real support on the pins. this is demonstrated when the nuts are loosened and the pins can be literally pushed back and fro; more in the direction of wheel rotation than opposite.
on one of the brake plates, with the nut undone and dial gauge touching it, it has deflection of 0 against rotation and a whopping 1mm in the direction of wheel rotation. 2 items are jointly responsible for this:
1- the pin(s) resting only on the hex flange (which is small, 15mm across the flats and 17 at the corners)
2- the hole in the brake plate is oval, and gets more oval with the braking experience it gains.
result are brake shoes that do not run square with the drum, holes get more oval and braking efficiency drops. not taking into account the flexing of the brake plates themselves.
anybody tackled this without getting replacement drums or fitting 2LS brake plates?
made a dummy pin with round 20mm flange and that already drops the movement from 1mm to just under 0.4mm (without any nut pulling it). pondering on reaming the holes from 9.51mm (⅜") to 10mm then fit new oversize pins with slight interference fit and larger flange (26mm) and filing a flat so that 2 pins adjacent each have the flats touching to act as a stopper when tightening the outside nuts.
what are your thoughts on this? again: NOT replacement 2LS stuff (with all respect to those that made them).