radarcarve wrote:Pita...Thankyou for all that great information! It is interesting that you mention VW's because I used to have a VW/Porsche engine rebuilding business, doing 600 engines a year. I could lay my hands on one and tell the mileage since new or rebuild instantly simply by pulling and pushing on the pully and feeling the endplay. That is the kind of thing I would hope to find on an old airhead, but can't, it seems. So, all your suggestions are very valuable to me. I currently ride a 2004 R1150RT, but I think I shall sell it and buy something like a 70's or early 80's R80 or R90. I hate the fact that I cannot do all my own work on the '04, what with all the electronics, and an earlier airhead is right up my alley. I have always been a seat of the pants kind of fellow... the last airplane I built was a Corvair powered Pietenpol...
Thing is half a VW motor, dry clutch is within a couple mm. Cam under crank, flat tappets and pushrods to overhead rockers. No wipers on the guides, various bearing arrangements on the rockers. Massive crank mains and thrust bearings. Short of running it out of oil, last half a millon. iron liners early, nikasil later, stroke constant except some oddballs, bore changed to make various displacements. Cam chain, double row early then single. Alternator directly off the end of the crank, points and mechanical advance off the cam nose(hall sender for electronic ignition later), oil pump off the back. Big flywheel early, lighter "clutch carrier" later. Starter on top under a cover. roughly the same layout as the 1150. Shaft and rear bevel drive, splined rear wheels except the 80g/s and the later monoshocks which had a single sided swing arm and bolted wheel.
Pick the technology you want to deal with and the year can be determined. But it's all pretty easy. The power and handling won't touch the 1150. he later monoshocks had the better suspension and brakes and the detuned motors can be fixed...
Edit: FWIW, you can pull the timing plug (left rear of motor over carb) to view flywheel rim and pry it gently w/ a screwdriver to feel the endplay. Don't think you'll feel anything tho'. It's a tight clearance set by a pair of thrust bearings sandwiching the block at the front. Exception is the early clutch carrier models. The carrier was riveted together and the rivets failed sometimes. The "flywheel" would do all kinds of moving on the blown rivets. You can spot a clutch carrier model (I forget the year it started, well past '74) because you won't see a continuous flywheel rim.
