Hinckley 865

The heart of the new Bonneville T100 is its 865cc vertical twin engine. This power plant combines classic Triumph looks with post-Japanese-invasion engineering. The head is obviously inspired by the rightfully famous Delta head, the sharpest looking head ever designed.

The 865 is a dual-overhead-cam engine, like the classic Honda CB450. As a kid I dreamed about the 450 when I wasn't dreaming about Triumphs. And I feel like my T100 is a fulfillment of both dreams.


Despite the overhead cams, the 865 isn't a super high revving engine. It develops its peak 66 hp at only 7200 rpm. Compare that to the CB450's 43 hp at 8500 rpm! But the 865 delivers at least 90% of its peak 52 ft lbs of torque from around 2700 rpm to redline. The Bonnie has the smoothest power curve of any bike I've ever ridden.

The finning on the head and cylinders is modest. Air cooling is supplemented by an inconspicuous oil cooler. This helps the big engine to more closely resemble classic era twins, some of which were heavily finned and looked larger than they really were.

The compact upper end of the engine sits on a substantial bottom end, giving the engine a distinct look. It also contributes to a low center of gravity, and that translates into great handling.

The 865 engine has been built since 2006 and is already legendary for its performance and reliability. It is a size upgrade of the original 790 engine that has performed reliably since 2001.


They did some fancy designing to make the 865 look like a classic Triumph engine, including an oil return tube that looks like a push-rod tube and deliberately placing the large engine cover on the left and the traditional "Triumph Triangle" cover on the right. This configuration required a right-side final chain drive, which is fine with me.

The engine is clean looking, despite the addition of flexible oil lines running from the head to the small radiator-like oil cooler mounted in front of the engine. Air pollution gadgetry is largely invisible. The air injector lines blend in with the spark plug wires they sit next to.

The new Bonnie motor runs so vibration free that, with the super-quiet stock mufflers, riding a new Bonnie is like riding an electric motorcycle. It's reported that the vibration damping engineering was too good at first and that a little vibration had to be engineered back into the engine for "character." They must have added very little. This thing is smooth.

The 865 is no racing engine but it's no dog, either. A completely stock Bonnie will go from 0 to 60 mph in five seconds and reach a top speed of 115.

Presumably, if you want to go faster than everyone else in town, you'll buy a faster bike. But if you want "enough" power and more than enough quality, you can't beat the Triumph 865.