Isolastic thrust washer material question...

I'm checking out the isolastic mount condition on a 1972 750; it's been over 20 years since the last visual inspection.

The thrust washers appear to be in good shape but I have a question regarding different materials used over the years.
These were put in the bike over twenty years ago so I don't recall the source. I still use the stock shim system.
The plastic washers on the bike are 0.065" thick. The Haynes manual calls them PTFE (teflon)washers.
I think I recall that these washers were made of a brown/copper colored material also.

What is considered the latest/best material these days?

There was some bronze impregnated PTFE thrust washers . Currently I think you'll find PTFE washers , there are hard enough and do not wear ( as I ride less than 30 years ago it's less of a concern )

Bob Z. said:

I think I recall that these washers were made of a brown/copper colored material also.

What is considered the latest/best material these days?

Click to expand...

The genuine 064748 washers available from Andover Norton are still the bronze PTFE type as far as I know.

Norvil sell their own nylon 064748 washer which they say, lasts longer than the genuine AN item.