The sight glass for the master cylinder was clouded and leaking so I removed it, only to realise it is 16mm and the only replacements I can find online are 18mm or 14mm, has anyone changed this before and where did you find a replacement?

Not seen any replacements listed in any parts catalogues from Yamaha. Next item up would be the actual master cylinder. You might need to use a donor and create the best one from the two

Hey Luke,

Check the below link, somebody reproduced these a few years back, maybe he can help you with it.

https://rdlccrazy.proboards.com/thread/ ... ight-glass

Hi there

On the XT600 models the glas is 18 mm, 16mm is the inner diameter of the Aluminium ring that holds it (plus an o-ring) in place. May the same on your XTZ750?

You can buy a 18 mm unit and transfer the glas only as shown here:
https://www.xt-foren.de/xt-phpbb/viewto ... as#p173660

Or maybe the new ring fits the master cylinder anyway and you can use the complete new unit.

Andy