July 2024
1974 Triumph T150 Trident 750
This bike had been in my care several years earlier, albeit with the different fuel tank seen here. It got a major engine sort out then after discovering worn out bores and a cracked cylinder head, even though it had come in with a nasty knock which turned out to be a primary belt drive pulley in trouble.
When completed it had proven to be something of a hotrod, what with an aggressive exhaust note plus some extra urge supplied by both the large bore three into one into two plus the reduction in primary mass due to the belt drive arrangement - my first experience of such. It sure had an instant throttle response thing going on.
During subsequent use the clutch cable I had fitted failed due to an end pulling off after I had recently paid the 'experts' to shorten the inners on a pair of them. I had supplied the other cable as a replacement but it could not be made to function properly, so the bike came back to sort that.
Turned out that there were a number of issues involved, the first one being that the 'experts' had shortened the inner half an inch more than requested, which is a pretty stupid error. The second was a fault of the original cable in that the ferrule at the primary end was too big to fit into the abutment. That was easily sorted by drilling the well-used abutment to suit. These days I prefer to use the L P Williams modified abutment which features an extended cable guide down into the primary outer case, whose purpose is to prevent primary chain oil from coming out of the abutment. It does.
Anyway, here we have the now firm fitting cable and abutment.
The second problem was to do with the slightly wider handlebars, which had stretched the cable a bit too tight having run via the right side of the steering head. I simply rerouted the cable along the left side of the frame spine then up and over the tacho mounting bracket.
End result was a very pleasing and compliant clutch lever action.
With these items attended to I attempted to start the bike, but no end of prodding would elicit the desired result. I checked the spark plugs to find that while they were iridium jobs, they were excessively fuel fouled. They were also 'R' type which meant they were adding a resistance into the spark plug leads. As it happened, the leads also had NGK suppressor caps fitted, so we effectively had two resistance items in each plug lead, when only one or none are necessary unless your flavour of electronic ignition demands one.
A lot of ignition setups have built-in losses to begin with, so I do not encourage the use of anything extra that reduces the spark energy. I replaced the old plugs with something new - called 'split-fire', which has a forked earth electrode designed to produce two sparks instead of one. Good idea if it works. They do not have any built-in resistor, and that was my main requirement.
I then discovered that the choke cables fitted to this bike had frayed inside their outer covering, and in fact the chokes were partially on at all times, which may explain the fuel fouling of the original plugs, but it was also interfering with normal starting practices.
That led to the removal of the entire choke system, as there was little reason to buy new choke cables when the choke was not normally used on the bike.
It sure cleans up the carb area and simplifies the routing of the numerous bits and pieces that can interact badly with the linkages.
The removal of the internal choke mechanisms inside each carb also lightens up the cable action at the twistgrip, so life is a little easier for the pilot.
Happily the bike now lit up first kick from cold, and I was treated to another brief refresher on what this beast has to offer. It does impress in many ways. Apart from a brief fine tuning it seemed we were at the finish line, so everything got buttoned up.
The owner showed up a few days later and was going to ride it home, about 60 miles away. It started first kick which was a very good omen. While it is still technically running-in, it seems to have bedded in well, and it is doubtful it will need any attention for a long while.