SHED GREMLINS & QUICK FIXES

The Moto Morini Corsaro 125 I rebuilt several years ago has given sterling service and has even been to France, conquering several mountain passes. It proves that a small machine can do anything a big machine can do (but slower!). Similarly, my Triumph T100 from 1955 is super reliable. These two machines are my first choices in all weathers– until last week, that is, when they both let me down. Or did I let them down?

The Triumph performed perfectly on the Saturday and covered over 200 trouble-free miles. On the Sunday, at the start of a VMCC run with an audience, it refused to start when normally first kick and it’s off. The problem was quickly evident: the cap of the Lucas magneto had become loose. A simple fix then. Err, no: the threads had succumbed to years of vibration. The solution was half a French wine cork jammed between the primary inner cover and the magneto cover to firmly hold it in place. It works so well it might have to be patented; just the right amount of pressure and easy to shape.

So the Triumph was back on the road again until a more permanent fix could be found. The (hopefully) permanent solution was a newly machined magneto cap. This has revised thread diameter to give a much better fit, and 12 flat machining to enable good tightening with a custom alloy spanner to suit. It was quite complex to machine something like this, which was previously a cast item.

The Morini wasn’t exactly straightforward to fix, either. It came back from France having completed many foreign miles without a hitch and went into the shed for a rest over winter. Upon revival it started misfiring after about two miles and then – nowt. It had fresh petrol and the spark was there but weak (but then, it is only a flywheel mag). I changed the plug, replaced the coil, HT lead and suppressor cap to get a slight improvement but still not perfect.

I cleaned the carb and filter, checked the points and auto advance, and all seemed to be good. Checked the condenser, which I replaced last year, and that was fine. So as a last resort I checked the valve settings. This required removing the valve cover on which I have an engine earth fitted to one of the locating screws – AHA! The cable, which was soldered on, fell off. The soldered fixing had suffered with vibration from the engine and was probably only held on with the shrinksleeving over it.

I connected a new earth with a crimped connection. Went for a ride and it worked well up to 60mph. The Morini is a quick machine for an old 125! I was always suspicious of soldering – now I will crimp.

Problem solving on old bikes requires a bit of lateral thinking sometimes, and none of the issues are what appear in the manual (if you even have one). It’s probably better for the brain cells than Sudoku. In future I will keep a wine cork in my tool kit; you never know what it might be useful for… Stu Thomson, member 2256

If you need any help emptying a few wine bottles so you can have the corks, just say… FrankW