I picked up my bike from the mechanic yesterday. It had been in for about 6 weeks now so it’s been a long time since I was last out on the road! The main jobs that needed to be done were that the front suspension forks needed to be rebuilt (the seals were leaking oil) and the engine valves and valve guides needed replacing (as I mentioned in my previous post entitled Replacement valves, guides and springs). But when the forks were taken apart we found that the tubes were rather worn and pitted and so must be replaced if the new seals were to have any chance of keeping the oil in, and the valve springs were so badly work that one actually snapped during removal. Therefore it’s taken a while to get the relevant parts sourced and shipped across from the UK.
The good news is that the engine now seems to be running much better than ever with a whole new lease of life! The exhaust note has completely changed and it sounds much more punchy, power and acceleration also seem to have both improved.
So off I set for the hour-or-so journey home just as it was beginning to get dark. I thought it a little strange initially when I couldn’t see my headlight reflecting on the back of the cars in front of me, even when flicking on to high beam, but assumed that maybe it wasn’t quite dark enough yet. But when I stopped for one of the toll booths I decided to get off and double check and found that the headlamp was emitting only the faintest of glows. So it seemed that the battery must not be charging for some reason and was therefore now pretty flat.
Thankfully though I had fitted LED lights to both the stop and tail lamp, and also to the side and pilot lights in the headlamp. So I switched over to these, rather than the main filament headlamp, and they still lit up quite nicely. That’s one of the great things about fitting LED’s instead of conventional bulbs – they require so little power (only a few milliamps) to light up quite brightly so they go on working even when the battery is almost completely dead. Apart from not being able to use the horn when various minibus and taxi drivers tried to cut me up, I was able to get home quite safely relying on only the LEDs.
So what was the problem with the charging system I pondered. Referring back to the article I wrote a while back on how to check a Lucas charging system, I decided to get the voltmeter out. It turns out that the dynamo is the problem as it’s not producing any volts whatsoever at any engine revs. The bike had been stood unused for about 6 weeks or so, so maybe the dynamo had lost its residual magnetism? I tried repolarising the dynamo (as described here) but unfortunately the battery was way too flat to be able to do much.
Therefore I had no other option then to put the battery on charge overnight to get some life back into it. I checked the battery voltage with a multimeter and it was only reading about 10.1 volts which for a 12v battery means it is very discharged!