Triumph TR5-250 Clutch Master Cylinder
The TR5, TR250 master cylinders were continued unchanged well into TR6 production. However on later TR6s, the bore of the clutch master cylinder assembly changed from 3/4” (0.75) to 7/10” (0.70). The change very effectively lightened the clutch pedal load. The downside was that it aggravated the problem of insufficient clutch clearance on a mechanism that was worn or had a broken tapered pin in the cross shaft. The later, smaller bore diameter master cylinders may be used to replace earlier types.
If a repair kit is required, before placing an order the cylinder bore diameter must obviously be identified (don’t assume because you have an earlier 6 cylinder TR that you have an earlier cylinder fitted). This is simply achieved by reading the size off the exterior of the cylinder.