Clutch issue

[Stinowino]

Hi There,

I just bought myself a 1979 bmw r65 and he's doeing great but one question. I'll try to describe it as good as I can in English :-)
I adjust the clutch as described in the manual and then it goes smooth, but after a half hour riding the clutch gets harder. I mean the clutch takes on abruptly then.

Anybody recognises this?

Thanks!

[Barry]

I don't recognise the symtoms of the clutch becoming abrupt after some use but airhead clutches are by their nature a little abrupt compared to typical multiplate motorcycle clutches. 

It might be worth having a look at the clutch release bearing which on a 79 is a radial needle roller bearing which is not a very good design.