Thu Apr 24, 2014 3:49 pm
In the end I replaced with a new tensioner. I can see what the tensioner stops do, however the spring tension is clearly stronger with the new part than the 50thou km part - linear difference of the guide was around 12mm with wear another 1-2 mm. The new part immediately stopped the tensioner clanging against the clutch basket during start-up, but the intermittent "slipping" noise stayed around a bit for the first run, only at idle. After a short run the noise hasn't returned - phew!
FYI the motor runs cleaner, faster revving with more power - noticeably. Not sure how the physics work but I surmise the alternator is now working more efficiently and therefore providing more spark. This makes sense as one of the symptoms of a worn tensioner is a flat battery (which I had only once), but again not sure how the physics work.
So all in all I think that replacement was the right option.
Sun Apr 27, 2014 8:58 pm
nice work on the fix

glad to hear you got it sorted out