Winter 2002-3 work & repair.
2002 was the year I made most use of the bike. Lots of driving in Norway, then transported it to Austria to de the Alps. After the Dolomites, Provence & more the plain main bearing showed signs of wear, and a quick check showed very feelable up-down movement in the crankshaft. Still possible to continue driving till the winter came. Stripped down the engine & decided to try fitting a new bearing myself, always interesting to do new things. Honed out with rudimentary tools, result is "very close to OK" regarding clearance, how long it will last I dont know. Started up nicely with a good sounding engine, all well the first few 100s miles (but a nervous rider). Last experiment before a timing side bearing conversion.
Fitted a new Amal 276 to replace the (very good) one I had, problem it being a 15\16, for a 500 or something, & a left side float. Imagined a 1 1\16 should give a little more power. Got a little improvement at high speeds, but not much. And the new carb gave a surprise, having the float on the right side as is original on this bike. With the old left side float I had no problem when using the side stand, as when the bike was tilted to the left the float level went below the drain hole in the jetblock. No spill whatsoever. When tilted left at stand still the new & "better" carb leaks horribly. Stupid me, who still thinks things should IMPROVE by spending money. I HATE petrol leaks. Now I have to be very careful to cut of the petrol supply either a little before stopping or letting the engine idle for a while with the petrol off to get the float level down before parking the bike. And tickling has to be done exactly right or else... Never had to worry about catching fire before, suppose Ill get used to it.
A useless investment was the 2 brand new good looking petrol taps, in original pull-on style. They leaked much more than the 25 years old ones all brass taps I had. The cork inside was very bad, leaking + some pieces of cork found their way into the carb & float. F*** + D*** it!! I threw them in the garbage & fitted a pair of industrial grade brass\stainless steel ball\nylon taps, not original looking but perfect from 1st second in use, & half the price of the 5th class new taps.
Gave the magneto a check, new points and some more work to get LR timing spot on. After refitting it worked for a while then found out it was time for a strike. The secondary HT windings went open, the wire INSIDE the slip ring (old fibre type) was loose. Judging from the burnt colour of the tip, this can have happened a long time ago but the spark was able to jump the gap. Fixed it temporarily, a new slip ring is on the shopping list. But I do not really complain, it was the first ever road side collapse, in the sunshine & close to home. And it didnt take long to get the sparks back. Still keeping the trusted magneto. Dead ignitions due to battery\charging\electronic problems are not uncommon, a well maintained magneto is still a very good device. The replacement pattern points did not fit particularly well, had to try a few before I found a set that was close enough in dimensions & tolerances compared to the old original Lucas points I had been using. Still had to grind it to get a flat contact surface between the points.
Inspection of the rest of the engine showed very little wear, pistons, drive side roller, bores, valves, cam, crankshaft bearings being very good (approx 12,000 km since rebore). Clutch friction plates show they have been used (lots of low speed twisting mountain roads) but still good for some 1000s of miles. It failed temporarily once, on a very hot day in the middle of the Monaco traffic jam, impossible to disengage, had to stop for 1\2 hour to cool it, then it worked fine again. Suppose the plates expanded extremely due to overheating. Only engine concern except the plain main bearing, is too much piston ring gap (reacted to the gap already when receiving the cylinder + new piston\rings back from rebore from SRM, wonder if they fitted standard rings instead of 0,5mm oversize). So a new set on the shopping list.
Went down from 21 teeth to 20 teeth gear sprocket (19 stock), was happy with 21 for highways, but 20 seems like a better compromise acceleration\relaxed 4th gear rpm.
All in all, looks like the A10 will provide lots more enjoyable miles this year too.