RD master cylinder rebuild kit question(s)

[Economy Cycle John]

There's also the option of a reproduction RD MC. It's the whole assembly and lever. They look and function just like the originals and are $85, preassembled ready to mount and bleed.

https://www.economycycle.com/shop/yamaha-rd250350400r5ds6ds7-parts/frame-related/brakes/front-master-cylinder-kit-rd250350-reproduction/

[m in sc]

 

[RDDave]

I have seen those complete masters. They 'look' good. I will try putting a kit in mine, FIRST. Since the bore is clean, it shouldn't be that big a deal.......IF.... I get the right kit with quality pieces.

Fail that, that master will be the next step.

 

[m in sc]

yeah if the bores good should be fine. most aren't, even super low mile bikes. you got lucky.

[RDDave]

yeah if the bores good should be fine. most aren't, even super low mile bikes. you got lucky.

Maybe..........for a change.

[scully]

they all have the same parts.

I'll be honest, the 5/8 master is too big even on a stock setup, brake feels wooden to me.

on my 72 r5 w rd front and stock brake, i run this exact unit.

https://www.ebay.com/itm/393221734319?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=3jd7hlyvqfs&sssrc=2047675&ssuid=9DXeqLNdSLW&widget_ver=artemis&media=COPY

Wood like feels is a perfect description evn back on my old tx500 back in the 70's :)....So Mark are you saying a 13mm master feels better as I'm looking for a new master cyl for my 400 '''' just asking :)

[m in sc]

minesa 14.3 or whatever that was, but yes. 13 imho is too small, 14feels perfect w a stock twin piston  rd caliper

[DesmoDrew]

   And after getting the M/C sorted, Don't NOT rebuild the caliper as well.  Brakes are a 'system', not just a collection of parts, and spending time/money at one end and not the other is not the best choice.   

[RDDave]

The caliper is already done. Getting the pistons out took a little doing, but I got them. Just waiting on the master cylinder kit now.