My bike, bought about 30 years ago, has been at the back of the garage for a few years. With the continuing restrictions because of COVID-19, and the almost total lack of vehicular traffic, I decided to dust it off so to speak. It's a Claude Butler that proudly displays the message 'Hand made in England' on a rear fork. But it weighs a tonne compared with the modern alloy or carbon models.
Unfortunately it needed a bit more than a dust off. In fact as it had been kept under plastic dust wasn't really an issue. What was an issue were the gears. The selectors were clearly not engaging with the selector mechanism so it wasn't possible to effect any gear changes. So I set about exploring the Shimano Exage 400LX system.
When I dismantled the selector for the rear dérailleur the reason was immediately obvious. The original grease had hardened and the small spring that kept the pawl engaged with the selector ratchet was effectively glued in the open position by the old grease. WD 40, gentle brushing and some light 3-in-1 oil got everything working again. But I had released the selector cable to take tension off the selector mechanism and because the end was badly frayed I couldn't get it back through the sheath of the outer.
I ordered a kit with two new Shimano inner cables, a length of new outer sheath and the fittings to put on the ends of the cut outers. And a decent cable cutter, having seen what a mess a pair of pliers made when I cut off the cable end cap from the old cable.
Replacing the cables was easier than I imagined. The design of the selector housing allows the cable to be pushed through and removed, and the new one installed by the reverse procedure. The outers were cut to size to match those removed, although it was necessary to ensure that the ends were 'open' after being squashed somewhat by the cutter. Next came the setting up, or indexing of the dérailleurs.
There is plenty of advice on the internet. I used the instructions from The Cyclist website. The rear dérailleur wasn't too bad to set up. I had to do a bit of fine tuning but it didn't take too long to get to the point where the gears changed and the inner and outer limits of movement were set. Sometimes the change jumped two sprockets but I think this might have been because my selector mechanisms were a bit worn, or perhaps a bit too liberally oiled! I'm not sure whether the light oil that replaced the old grease might have been just a bit too lubricating, causing the pawl to slip over the ratchet. But it was good enough.
The front dérailleur was, however, much more of a problem. I again followed the relevant instructions from The Cyclist website, but this time I couldn't quite get the dérailleur to change smoothly, or for that matter completely reliably. The mechanism is cruder than at the rear, a guide pushing against the chain, whereas at the rear a cage guides the chain. Changing up to the large sprocket didn't always complete. After much adjusting and re-adjusting I got it to work but a bit unreliably. On reflection, I seem to remember that this dérailleur was alway a bit unreliable even when the bike was newer. It's also a fact that I rarely shift the front, and as I now live in the Fens there is little need for an extreme low gear. So, I decided to select the middle sprocket as for my purposes the rear 7-gear cluster should be more than adequate.
I took it out for a 20 minute spin, with some off road, and within the restricted range of gears that I used things seemed quite smooth.