Off to the MOT

For readers outside of the UK, the MOT is a mandatory annual test that all motor vehicles must pass if they are to be used on public roads. MOT stands for Ministry Of Transport. My bike had been off the road and without the need on an MOT for two years so, before I could allow her to roam free once more on British roads, I had to get her to my wonderful local MOT tester.

Although of course I had repaired, refurbished and/or refitted pretty well all of the running gear, I rechecked everything I could think of and road the bike backwards and forwards on my little drive. So the night before my MOT appointment, I ran the bike through at set of checks I've got used to performing in advance of the annual exam. I couldn't find any obvious problems but knew the headlight wasn't working as well as it should. I'd spotted that the wiring from the main loom was thin compared to the little harness that connects from the loom to the H4 headlight bulb.

The feel of the motor was just superb in these little tests. I had expected it to be running unevenly because I had reset the carburettors in cleaning them and so thought they'd be out of balance. As it happens, my attempt to get the carbs somewhere near by visually adjusting the DV carb throttle plates so they were all opening at about the same time with the throttle. The whole feel of the bike was just fantastic. I'm sorry that this is such an emotional and uninformative term to use. It's just that, for me, it was everything and more than I had hoped for. It's true, the gear selection felt a bit harsh - a real clunk - but I was used to this from my Daytona 900 when that motor was younger. The sense I had, just allowing the motor to pull the bike along at walking pace, was that it was willing and turbine smooth. No juddering, hesitation or shaking: just an even solid thrust.
This is how she sounded and ran at that particular moment:

You will see that the digital oil pressure and oil temperature gauges appear to be working correctly. They are powered from a spare coil positive wire courtesy of the fact that the loom was common right across the whole range in 1991 (the four-cylinder engines need two, the three-cylinder engines use three coils). So when I change the engine kill switch from off to on, the gauges are powered up and flash all segments of their LED display in the process. The then start to read oil temperature (right-hand gauge) and oil pressure (left-hand gauge). I discovered that the lowest temperature that the temp gauge can show is 25 degrees centigrade. So when it shows 25, it doesn't mean anything at all. The fact that it starts up in the 40's in this video is because the motor was warm from the first startup. The striking thing for me about the oil pressure is how high it reads when the engine is cold. Cold oil must be a lot thicker than oil at the correct operating temperature. I shall write more on this in a later posting. I had decided not to refit the fairing panels until I was confident that everything that would be hidden by them was working properly and leak-free.

Setting off for the MOT next day threw up my first problem: she was only running on two. I couldn't believe it after the 'pre-flight checks' the previous evening. Oh well. I had an appointment to keep so set up in lumpy fashion for the test. 

I have got to know the MOT tester at my local bike shop over several years. I never ask for any special consideration, though probably get it. I like the guy very much because he really knows what he is doing, is friendly and considerate and won't cut corners on the test. He found two problems with the bike. One was not unexpected: the headlight beam was out of adjustment. The other was that the electrical cables from the right-hand switch gear were catching as the handlebars turned from lock to lock. He allowed me to adjust the former and solve the latter with a cable tie. Everything else was in order and he complemented me on the cleanliness of the underside of my engine.
What a guy!
He said he thought there was a mistake in the wiring of my H4 bulb because the dip beam was very yellow in colour. He said this can happen if the wrong H4 terminal is earthed. So that needs checking. The dip beam on early Trophys is notoriously poor anyway and I had decided I'd address the fact that the main loom appears to have under sized feeds for the headlight anyway.
The nett result is one 1991 Triumph Trophy 1200 back on the road in Britain, 21 years after it first left the Hinckley factory. A great result for me.

 

We exchanged some thoughts on the rough running engine formed a plan to sort it out.