Footnotes to Triumph Overhaul Manual

¹ The Overhaul Manual says that the newer E9525 (70-9525) connecting rods were introduced in 1967 at DU47006. Woolridge says at DU81209. An outlier, Nelson says they were introduced in June of 1969 (Nelson, J.R. Bonnie The Development History of the Triumph Bonneville. p.188, 2nd ed. 1994. Foulis/Haynes). Error? In addition to thicker small ends, newer items were made for UNF bolts, resulting in changed torque specs.

² The Overhaul Manual refers to the crankcase parting tool as Triumph special tool Z151. However, all the sources I can find say that Z151 is a "universal sprocket puller" for removing the engine sprocket.

³ The Overhaul Manual (1967) says that ring end gap should be .010" to .017". However, Triumph Service Bulletin (Twin)11/71 updated ring end gap to 0.012" - 0.018" in 1971. (Also see: "Ring Gap" in The Bonnie Ref.

⁴ The Overhaul Manual says to torque the headbolts to 20/25 lb.ft., but the WS Manual in General Data, Torque Wrench Settings gives the correct figures of 15/18 lb.ft. (See: "Head Bolt Torque" in The Bonnie Ref).

⁵ The Overhaul Manual says to adjust valve clearance to .004" intake and .006" exhaust, but the WS Manual in General Data, gives the correct figures of .002" inlet and .004" exhaust.

⁶ The Overhaul Manual says to gap the spark plugs to .020", but the WS Manual in General Data, gives the correct gap of .025".

⁷ The three variations of this tool are the subject of a portion of Triumph Bulletin No.66-2P. The pertinent portion is here on TED.

⁸Most Z121 pinion gear remover tools sold today will need to have the inside radius of their jaws ground slightly before they will fit behind the crankshaft pinion gear.