I had read that the Triumph 2000/2500/2.5PI Register service notes were recommended for triumphists with PI.
Having bought them I reckon that it was money well spent. They are full tips gathered over the years by club members. http://www.t2000register.org.uk/
In case you can not read the above here is what it says.
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SERVICE NOTES SUPPLEMENT
The long-awaited second volume of our invaluable guide to maintenance and problem solving from the pages of “SIXappeal” 1993 to 2001. Written by our experts and members. Price £12.50 plus £4.00 p&p (UK).
ALSO AVAILABLE AGAIN IN A LIMITED EDITION - SERVICE NOTES Volume I
Still in demand this is the original volume covering the technical bits of “SIXappeal” 1981 to 1992. Price held at £20.00 plus £4.50 p&p (UK).
SPECIAL OFFER - while stocks last
Buy both volumes of Service Notes for only £30.00 plus £7.00 p&p (UK).
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You can save the postage if you buy them at a show. I got mine at the NEC classic last month.