I read on an Internet forum that it was advisable to check the gear lever mechanism once in a while. Underneath the vehicle, it is exposed to road salt and spray, and if not looked after can cause clunky gear changes.
So in addition to my normal weekend maintenance I took it off so that it could be cleaned and greased. First of all one has to remove the belly pan in order to get access to the gear change mechanism. With the belly pan removed, I took the gear lever off. At least, that was my intention. Things don't always go according to plan.
As I started to undo the clamp bolt holding the gear change lever on the gearbox shaft, it sheared off. After some drilling, hammering, and swearing, I finally got the gear lever off the bike. Drilling the sheared bolt out had damaged some of the threads, so I re-tapped them. During the re-tapping, the clamp mechanism broke in two. So this is yet another of those items made from high-tensile cheese (other examples being the clutch and brake fluid reservoirs)! Fortunately I have a mig welder (as I used to own a Land Rover) so I welded the two parts together, giving me a usable gear lever again.
Apart from that, it was in pretty good condition anyway! I put it back on the bike and re-attached the belly pan.
The following day on my commute in to work, I needed to change down a gear. Pushing down on the lever with my left foot, I was surprised to find it gently subsiding underneath the bike. Still in 5th gear, I managed to take the next exit which happened to be a motorway service station. In the parking area, I removed the belly pan and had a look. The bolt was missing, with the result that the clamp mechanism was just rotating around the gear shaft. Not carrying a stock of bolts with me, I called the AA (Breakdown assistance).
An hour or so later the AA man arrived and from his toolbox produced an M6 bolt and nut which he proceeded to fit. I was soon on my way again. I then discovered that the gear lever had been reattached at the wrong angle and was actually too high; in order to change gear I had to completely lift my foot off the footpeg to reach the lever!
When I arrived home that evening I once again removed the belly pan and the gear change mechanism. Reattaching it in the correct position, I tightened the bolt.
Snap. The clamp mechanism split in two again.
I bought a second-hand one from Ebay but until it arrived I used a radiator hose jubilee clip to hold the clamp mechanism together.
It just shows - that old adage is quite true. "If it ain't broke, don't fix it!"