TRIUMPH T120R
The oil-in-frame 650 Bonnie can cost half the price of an earlier T120R incarnation. But does that mean the later model is only half as good? Paul Henshaw takes one for a quick spin to find out
The oil-in-frame 650 Bonnie can cost half the price of an earlier T120R incarnation. But does that mean the later model is only half as good? Paul Henshaw takes one for a quick spin to find out
Working with classic bikes as I do offers an amazing perk of the job. I get to ride many of the machines I work on and get a good idea of how they go, handle and stop, as well as any little quirks they may have. It’s a great way to get to ride all sorts of machines that I would otherwise probably never get my hands on. This really is the absolute upside of what can sometimes be a dirty and fiddly but enjoyable job. I’ve been able to experience a huge number of machines of diverse ages, makes and models. I also get to blow the lid off the odd myth or two, once in a while.
Take this 1972 Triumph T120R, an oil in frame model. These are nowhere near as sought-after as the slightly earlier oil-tank models, so these later versions can be bought for not much more than half the asking price seen on some earlier Bonneville models. To my mind, the oil-in-frame 650 is much more than half an earlier, more pricey one.
The Triumph featured here was repatriated from the USA fairly recently by an owner of several similar machines. However, this Bonneville’s first port of call was the other side of the English Channel and then down quite a long way, where it shared space with some other, similar machines. While there, it loaned its timing cover to another unit 650 twin – and we will come back to this in a while. I have worked on numerous machines brought back from the US which apparently just needed ‘servicing’, but several turned out to need full engine rebuilds, despite appearing to be in good condition or even ‘restored’.
This T120R came to me as a fairly tidy non-runner, with just 8000 miles on the clock. That mileage was probably genuine, going by the general condition of everything. It had slightly matted paintwork and tyres made of Bakelite, with nice cracks in to boot. A preliminary check revealed no sparks – which was soon to be seen as a blessing. Attempts to get it going had been made, apparently, but the lack of ignition soon had it heading to me to take a look. New points were fitted – they’d even been gapped and timed pretty well, but they were shorted to earth. A quick sort out of the insulating for the wires going to the points, and tightening a loose condenser mounting nut (under the seat) soon gave big, fat sparks on both cylinders.
The engine still wouldn’t start, though. That was because of a green, toffee-like goo in the carbs. This had even got into the pilot circuit of one of the Amal Mk1s and was very difficult to shift but, finally, we had sparks, fuel, good compression and anything else required for the engine to fire. And fire it did. It ran beautifully, but the oil light was on. I removed the oil filler cap…
At this point, seeing a good amount of oil returning from the engine, it might have been assumed all was well and the oil switch was faulty. Except I happen to know that luck isn’t always a lady, so as a precaution I removed the oil warning light switch and connected a pressure gauge, and it gave no reading! Off with the timing cover to look for clues. One great big clue – there was no oil seal in the timing cover for the crank end feed! For that matter, there was no oil seal in the back of the points housing, either.
A call to the owner revealed that this machine’s original timing cover had been removed and fitted to a running stablemate whose timing cover had been cracked. A new timing cover had been bought and fitted to this T120 a while later – it would seem that new ones come bare, with no seals. Luckily, the engine had run for next to no time and a seal was quickly fitted. After that the oil pressure went through the roof and just the other basic servicing was done, as well as new tyres and fork seals and such.
The dulled paintwork was refreshed by my local painting wizard, Lee, who found he couldn’t get a good match for the gold paint, so the lacquer was carefully removed, the black panels were resprayed as they were scratched and the pin stripes were redone. The gold paint was intact, so it was polished and the whole tank re-lacquered – twice, as
the first time there was a horrible, bubbling reaction, much to Lee’s horror!
The engine started and ran like new and would tick over evenly at about 700rpm on the two original carbs. Time to try it out...
First off, the Bonnie didn’t strike me as particularly tall – a bit taller than the older, oil tank models, but not uncomfortably so. I never quite made it to six feet tall, so I am of a fairly average height. The centre-stand is a pig, though, almost hernia-inducing, although it provides plenty of clearance for when the wheels have to come off. The prop stand is easy enough to use by contrast.
The Triumph started easily; the cable-operated choke slides helping with initial cold starting on this one, although they could be opened almost straight away once the engine fired up. It pulled away smoothly and strongly, the clutch and gear changes were smooth and precise and the throttle response was very good, with no hesitation or flat spots. The exhaust note was healthy, but not as sharp or raspy as on earlier models, and the mechanical bits were pretty quiet.
The new K70 tyres were up to the job, and corners could be taken with confidence. I have never had an issue with the conical front brakes, although this bike could be slowed and stopped with greater ease than a similarly equipped Rocket 3 I remember riding…
Using the lights could be a bit of a fiddle. The ignition key is situated down on the right side panel and has to be moved to the next position after the ignition on slot. Then you use the rotary switch on the headlamp to select side or full lights, as well as the dipswitch itself on the handlebars. To be fair, I didn’t take this one out in the dark.
I usually rate a bike as being ‘good’ if it performs somewhere in the region of what you might expect for its size and type, without being a bit of a handful. Performance, handling and brakes all have to be up to scratch, but another, big factor is that it has to be FUN. If you are enjoying the ride, you will be riding better, rather than being anxious or distracted about noises, vibration, smoke and keeping up with (and slowing down with) other traffic. The T120 ticked all my boxes and when I learned that the owner intended to sell it, I almost did the sums to make an offer, but I may not have been popular with the management for that one. I will probably get to ride this machine again, some day, though, as the owner sold it soon after I sorted it out – to my brother-inlaw, who lives not a million miles away!
These bikes and their BSA oil in frame siblings are anything but bad bikes. They get a fair bit of stick in print, but I would suggest they are just as good as their predecessors, with possibly the odd improvement to boot. I can see where some might think they are not as good (ie. traditional) looking, but they are attractive and fun to ride. They can keep up with modern traffic with relative ease and, if they are in good health, they can achieve some pretty high speeds and distances without shaking themselves to bits. Some may well shake themselves to bits, and rattle and clatter, but I bet the majority of those may have been spannered rather poorly or had some vital part incorrectly fitted, or, like this one, not there at all! I have seen many more examples of this type of thing, more of which in the future...