1971 Triumph Bonneville T120R

Fisher Racing Products custom Triumph motorcycle


| July/August 2010



frp bonneville 2

Lean and mean: The Fisher Racing Products Bonneville weighs in almost 140 pounds lighter than a stock 1971 Bonneville thanks to an extensive weight loss program.

Photo by Robert Smith

1971 Triumph Bonneville T120R Fisher Racing Products
Claimed power: 57hp @ 7,000rpm
Tope speed: 130mph (est.)
Engine type: 649cc air-cooled OHV parallel twin
Weight (dry): 370lb (118kg) (est.)
MPG: 30-40mpg (est.)

The 1971 Triumph Bonneville T120R was the problem child of a shotgun marriage. It was responsible for Triumph missing that year’s U.S. sales season, and it just about bankrupted the company. So how did South African tuner and racer Nev Fisher turn this Ugly Betty into a custom Triumph motorcycle beauty queen?

The late Sixties Triumph Bonnevilles were, and still are, considered to be the best of the lot. But a major program of standardization was underway across the BSA Group, which also owned Triumph. For the 1971 season, BSA planned to use a new oil-bearing frame for both BSA and Triumph 650 twins.

However, the new Triumph frame had been designed around the BSA 650 engine, and when the first batches of frames were delivered to Triumph’s Meriden factory, assembly line workers found they couldn’t fit the Triumph engine in the frame without removing the rocker boxes from the cylinder head first.

The 1971 Bonnies were already behind schedule because of production delays caused by a shortage of parts — the result of teething troubles with a new computer system. The cumulative result was that very few Bonnevilles were at U.S. dealers for the critical April to June sales season. Other problems with the 1971 bike included a seat height only suitable for people over 6 feet tall, major frame failures caused by the center stand being mounted on the oil-bearing “sump,” and aesthetics only a short-sighted mother could love. The 1971 model is perhaps the least popular of all Bonnies.

Love conquers all

That didn’t stop Dave Carpenter from falling in love with his dad’s 1971 Bonneville. So much so, that a couple of years ago, he persuaded his father to sell it to him. “It dredged up all those feelings I had many years ago about riding those bikes back in the Sixties,” Dave says. But the reality of riding the old Bonnie, especially compared with Dave’s modern Triumph Thruxton, wasn’t how he remembered it. “This old Bonneville was in need of some serious work,” he says.

david_5
9/16/2010 10:34:52 PM

So, what did he do about the bogus leaf-spring gear indexer? I had a 71, even with two springs it almost always missed second gear. 71 A65L now, it has it's own set of bugbears. Nice job!


richard backus
9/15/2010 4:10:38 PM

Turns out we got the wrong info. It actually weighs 370 pounds, not the 260 we published. Richard Backus Motorcycle Classics


gerarddm_3
7/19/2010 3:26:47 PM

Reading the text of what Nev Fisher did to this '71 Bonnie, I can not understand at all how he shaved off 140 lbs to get the bike down to a claimed 260 lbs. 360 lbs, sure. But 260?!? He added some stuff as well as lightened some stuff, so WHERE did the massive weight loss happen? Those of us with older bikes looking to make them more sprightly would surely like to know details...


nev fisher
6/22/2010 4:30:08 AM

A very well written article! The weight loss, whilst significant, seems to have been overstated somewhat. I've asked Dave Carpenter to weigh the bike as a matter of interest. Apart from that the technical details are accurate and I feel honored to have one of my bikes featured in your top class magazine. Cheers!






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