TRIUMPH’S TERRIER

When it comes to Triumph’s tenacious four-stroke tiddlers, Mike Estall really did write the book on the subject. With all his experience and expertise, he might’ve expected an easy ride with a ‘recently rebuilt’ 1956 T15. Ah. Well…

When it comes to Triumph’s tenacious fourstroke tiddlers, Mike Estall really did write the book on the subject. With all his experience and expertise, he might’ve expected an easy ride with a ‘recently rebuilt’ 1956 T15. Ah. Well…

Before we meet the subject of this story, here’s a little bit of background history about the first Triumph lightweight model since the XO in the late 1930s. The T15 Terrier was designed as a commuter / learner machine with styling and colour schemes that imitated the 5T Speed Twin. The Terrier was a financial loss leader, aimed at pointing the rider towards the larger Triumph twins in later years, generating brand loyalty.

It wasn’t very long before it was realised that the Terrier had been ‘sent into this breathing world before (its) time scarce half made up’ (to quote the Bard), and was being seen as unreliable. Edward Turner’s dictum of ‘make the minimum amount of metal perform the maximum amount of duty’ had produced a machine that was underengineered and had been put on sale before it was ready. So it was decided that a public demonstration of its capabilities should be made. What better than an ‘End to End’ adventure?

The end result was a triumph (sorry). 1008 miles ridden in five days, all ACU observed. Average speed 36.68mph, average fuel consumption 108.6mpg, average oil use 6oz per machine.

Upon their return to Meriden the machines were stripped and measured, again in the presence of ACU observers, and no measurable wear was found.

Six decades later, that Gaffer’s Gallop was re-run to celebrate its 60th anniversary, and that’s how I met our featured machine, T15 20830, PYS 629.

It was originally delivered to Bell Brothers’

Glasgow emporium on 3rd January 1956. A friend of a friend in Cornwall had built it for the Gaffer’s Gallop and asked if I’d care to ride the bike in the event? After about three microseconds I replied in the affirmative!

I rode PYS 629 from Roche to Land’s End and back to Roche again, a total of about 110 miles, that being all I had planned to do. The bike ran like a dream, but I found it somewhat over-geared. I later discovered that it had a smaller than standard rear wheel sprocket, which made the bike labour going up some of the long Cornish hills. However it was an absolute whiz going downhill!

Afterwards, the Terrier was returned to its owner and later taken to a dealer to go on sale. Some weeks later I agreed to buy it as I had enjoyed it so much, on condition that it could be delivered to my house. A couple of weeks later PYS 629 arrived on my front door and the finances were settled. I was familiar with the machine so didn’t bother starting it when it arrived, just wheeled into my garage. The problems began when I decided to go for a ride…

Next morning the damned thing wouldn’t start! The petrol feed was OK but there was no spark. Oh great, I just love electrical problems. That Lucas PRS8 combined ignition

and lighting switch has seventeen terminals and is well hidden inside the headlamp nacelle. This was a bike that I had neither built nor wired and fixing it was not what I had planned.

Looking at the wiring visible from the outside of the nacelle revealed that the LT wire from the points and HT coil to the PRS8 had been cut and the short stub could be seen sticking out of the switch. What was going on here? The bike had run beautifully in the Gallop not that long ago. It had then been delivered to the bike shop where it had been on display in their showroom before being collected and delivered to me. I wondered what else I might find.

Closer examination found an alternator wire incorrectly connected, one wire in the loom completely missing and the wiring at the PRS8 switch itself was all over the place! Somewhere inside that northern dealership where PYS had lain, dark forces had been at work. There had been sabotage! This investigation took many weeks but I had other bikes to ride, so I didn’t rush things.

During the next year or more I covered over a thousand miles, including several trips of sixty miles or more, but other faults began to appear. PYS had come with a good Cub speedometer, but I found a Terrier type at a jumble and fitted it. It was OK up to about 40mph but after that it swung wildly. I removed the chrome bezels from each instrument and fitted the Terrier speedo face to the Cub instrument. Result!

Then the charging system decided to go on strike. I’d fitted an ammeter but the needle did not want to move, so a new ammeter was needed. I fitted a new HT coil as well – just to be safe! Then the battery died. It would not take a charge so I had to

buy a new one. The honeymoon was over.

By this time I must have lost my presence of mind. Too many electrical things were going wrong and I discussed matters with a friend who knows a thing or three about bike electrics. May The Lord bless Tony’s little cotton socks. He offered to rewire the bike for me. I supplied a new rectifier and left him to it. About three weeks later I got the bike back and all was electrically perfect. But by now other things needed sorting…

One of many drawings made for the new Terrier in 1952, showing the unit construction, 4-speed ohv fourstroke design

A pre-production Terrier from a Continental exhibition in late 1952

In 1953 Kent dealer Jock Hitchcock was an ISDT private entry on T15 107. He retired on the fourth day with ignition problems. You can see that the centrestand has already suffered a partial collapse!

almost a mighty The new model produced rpm, but it did have 8bhp at just under 5500 With an unladen a nice flat torque curve. lowly weight of 175lb this apparently top speed of roughly power output gave a and excellent fuel 60mph, good acceleration economy

Pilot’s-eye view; note the gear indicator. This device was useful for about the first thirty minutes

The photo was published in Triumph’s own newspaper, ‘Triumph News’, after the Terrier’s first public show at Earl’s Court. Anybody recognise anyone?

The inner workings…

could make sound trials jockey, decided that the Terrier Jimmy Alves, a Somerset dealer and very rode in the ISDT) (the same machine that Jock Hitchcock a good trials bike. He converted T15 107 story. The 199cc a Tiger Cub, which started a whole new and was very successful. He later converted today among ISDT, initialising their undying popularity machine was Triumph’s entry in the 1956 today’s trials fraternity

Almost immediately after the success of the Gaffer’s Gallop came the arrival of a rival at the Earls Court show. A 199cc sports version of the Terrier, called the T20 Tiger Cub, was displayed. As soon as the Cub arrived on the scene nobody wanted the Terrier anymore and sales dropped by two-thirds. It slipped out of production altogether by the end of July 1956

A student at the Triumph Corporation service school in Baltimore, USA

The Terrier and LE Velocette were rivals for police patrol duties. The LE got the job!

July 1987 at Founder’s Day. In the 1980s Mike converted a 149cc Terrier to 125cc (to make it suitable for a learner rider) by using a Kawasaki piston and sleeving the barrel

After Mike took possession of PYS, it was running a bit weak. He figured its carb needed a ‘3’ slide instead of the ‘4’ fitted and had to improvise. Using the good ‘4’ slide he measured the difference in cutaway height against a worn ‘3’ and found it to be 0.035”. An exhibitor’s brass plaque was, by pure chance, 0.035” thick so he made a template and soldered it on, reducing the cutaway of the ‘4’, to ‘3’. Success!

Doug Beasley’s ‘Double-knocker’ Terrier with an MV frame and Earles forks

In 2005 Mike acquired and later restored what he believes is the oldest surviving complete Terrier, T15 111, the tenth machine off the line. This bike, along with the 125cc Terrier and Mike on another machine all took part in the 60th Gaffer’s Gallop anniversary rerun

And here Mike’s Terrier. Jobs done: ready to ride and with flashers too!

The rear brake shoes were down to the rivets, so Mike sent them to Villiers Services who fitted new oversize soft linings. Both sets were mounted on their brake plates and turned on the lathe to fit nicely in the drum. The braking difference was phenomenal!

The rear hub brake lever was slack and could not be tightened enough to pull the brake on before the foot lever hit the back of the primary cover. The hub lever was turning on the brake cam squared end. Repaired with NOS parts

The rear brake torque stay peg had somehow come right out and become lodged between the suspension unit casting and the brake plate. There was no 7/16” thread left on the peg or in the casting so the peg had just slopped around in its hole until it fell out. The peg was turned down to a ‘clean’ diameter. Mike cut the end off a ½” x 20tpi bolt and tapped the same thread inside the suspension casting. The bolt end was bored to a 0.002 light interference fit with the peg and the new thread pressed onto the old peg. That bodge is still working…