I had some time on my hands today, so decided to get cracking on the pension fund (Rapide). I've had the bike for about a year and when I bought it I decided to enjoy riding it rather than rush to take it to bits, so this is all uncharted territory.
I must have been feeling very brave, because I decided to tackle the most scary job first - a look inside the timing chest. Why scary I hear you all ask? I'll tell you then. It's scary because you can easily spend over £1500 in parts alone to refurbish the potential wear and damage you may find on examination. But it turns out lady luck was on my side today. As I nervously eased the timing cover off, I was greeted by the sight of a lovely lightened steel large idler gear and shaft assembly and the general appearance of a nicely put together engine in good order.
The large idler gear is a bit of an achilles heel with Vincents, because originally the factory fitted them made from alloy. A clever idea, it was intended to expand at the same rate as the cases, keeping things quiet and in a constant state of mesh. Unfortunately after 25+ years, alloy gears are known to shed teeth and distribute the bits throughout the engine, so it's advisable to replace them with steel. This involves stripping the whole timing side down and then re-adjusting mesh (including the selection of the correct sized small gear on the end of the crank from about 20 different sizes. Quite a big job, and since the engine has been running so nicely, I'm loathe to disturb it too much.
So it's just a clean up, new gasket and seals and on to the next job. Watch this space for the next episode, as I get to the bottom of the mystery of the (gradually) vanishing clutch pushrod.