Black Bonnie: Triumph T120 Bonneville by MJH Performance Bikes

Triumph T120 Bonneville

In 1971, Triumph introduced a new oil-in-frame Bonneville, whose steel chassis held the bike’s oil in its 3-inch diameter backbone instead of a separate oil bag. These “Oilers” would also get a 5-speed gearbox, a front disc brake, and the 650cc engines would end up being bored to 750cc (T140) for some extra punch.

Triumph T120 Bonneville

There was a ton of controversy surrounding Triumph in the 1970s, including poor management on the part of parent company BSA, employee lock-outs, financial woes, and the unstoppable influx of trouble-free, high-performance Japanese machines like the Honda CB750 — stiff competition for the Triumph twins, which had reigned supreme in the 1960s.

Triumph T120 Bonneville

While the oil-in-frame Bonnevilles would never rival the Japanese superbikes in outright performance, they turned out to be solid performers in their own right — they had class, charisma, and that old British grit that’s stood the test of time.

Triumph T120 Bonneville

Enter our friends Hanns and Miguel from MJH Performance Bikes — a small workshop located in the heart of Malaga, Spain, in a building more than 200 years old. These two friends — one German, one Spanish — have a similar taste in motorcycles, which they admit often borders on obsession.

Triumph T120 Bonnevlle

Recently, we featured their Triumph X-75 Hurricane reproduction — a project that drew compliments from the original designer himself, Craig Vetter! Now the duo is back with this Triumph T120 Bonneville, restored and slightly modified with just the right modern touches.

Triumph T120 Bonneville

Originally, they were in the market for a BSA or Norton, a British classic with timeless lines and character — something that would still attract an audience today. But then they ran across this T120 Bonneville in Granada with Seville plates:

“It had always had the same original owner and his son put it up for sale due to lack of use.”

Triumph T120 Bonneville

A one-owner vintage Bonnie — hard to pass up! Originally, they had plans for a heavily modified cafe racer, but that presented a dilemma:

“We believed that with a legendary motorcycle such as this one, with so much history behind it, it would be a shame to make too many changes, as it’s very attractive with several small changes and a more modern look.”

Triumph T120 Bonneville

So Hanns and Miguel decided to proceed with a lighter touch, giving this T120 a more modern look while maintaining the classic and original lines.

Triumph T120 Bonnevlle

In this restoration / customization, they used original elements from a 2014 Triumph Thruxton, such as the two-up gel seat for with removable passenger cowling, as well as the risers, handlebars, and mirrors.

The original 1974 tail light was cut shorter, using the same lenses and blinkers. This made everything tidier out back while largely retaining the bike’s original silhouette. They also shortened the rear fender and adapted the original license plate holder to work.

Triumph T120 Bonnevlle

When they disassembled the air filter covers for paint, they found some dull aluminum lines and carbs that, with a bit of polish, would give the bike more of a cafe racer look. So they shined up the lines and gave the carburetors a set of K&N cone filters. They also polished the carbs themselves, engine covers, and more.

Other mods included shiny new wheel spokes in 306 or A2 grade stainless steel, new brake pads, cables, brake and clutch lines, and yokes. They also sent off a lot of bits and pieces to be chromed.

A set of megaphone type mufflers were installed and DB killers were custom-made to reduce the sound in the city enough to comply with European regulations:

“They give out a very special sound reminiscent of a Harley-Davidson.”

Triumph T120 Bonnevlle

All in all, this one gorgeous Bonnie that’s been put back on the road with just the right touch of modern style and function.

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Miguel & Hanns
MJH Performance Bikes®
[email protected]



  1. Beautiful looking machine, but unless I have missed it no mention of price!

  2. I love your stories and your site, but in every single story you write “Enter (name of builder here).” Can’t you use some other device to introduce the story? How about “That’s where so-and-so comes in,” or “Builder so-and-so decided he wanted one of these too.” It’s not hard.

    • bikebound

      Excellent feedback, Gabe. That device, while comforting in its familiarity, has become a crutch. Working on it!

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