850 master cylinder different? & Aussi in Philippines selling 13m bore kits

I think I read here somewhere that there is a difference in front master brake cylinders from 850 to 750. If that is correct what is difference and is there anyway to know difference? Also looking for name/address of Aussie living in Philippines that was selling a bore kit to 13mm on this site. Thanks.

'Early' ('72) master cylinders lack the threaded mirror boss of the '73 - '74 master cylinders otherwise they are basically the same. It's the 850 Mk3 master cylinder that's "different".

dennisht said:

Also looking for name/address of Aussie living in Philippines that was selling a bore kit to 13mm on this site. Thanks.

Click to expand...

Don Pender, member; madass140.

dennisht said:

IAlso looking for name/address of Aussie living in Philippines that was selling a bore kit to 13mm on this site. Thanks.

Click to expand...

You may want to consider a new master cylinder. A-N has reduced the bore to 13mm on the new ones, you will thereby avoid worries about the sleeve coming loose, etc.

-Knut

check www.tritoncycleparts.com

The Madass140 reline kit is alloy so you can be extra certain it will not budge by drilling and tapping for a 3mm grub screw from the handlebar recess on the master cylinder deep enough just to create a dimple on the sleeve. Adds 10 min to the install.

i had my hands on one of his resleeve kits and refused to use it. the fit was WAY to loose in the old bore for me to feel it was safe. IMHO the RGM kit is a FAR better design with it threaded in and a seal at the bottom end.

I had an RGM 13mm re sleeve kit installed 14 years ago. Increased braking power by about 15% and has never leaked.
It is still a poor performing brake even after a blanchard grind of the disc and new pads. My VERY effective 1970 TLS
triumph brake makes me wonder what NV was thinking in 1972 before they were in trouble. Before I would put any
more money into my existing front brake, I would seriously look at the modern alternatives.