The 2017 All-New Harley-Davidson Engine
Harley-Davidson is set to unleash its 2017 model range in late August with one of the biggest shake-ups in the motor company’s history – it’s set to introduce a completely new big-capacity V-twin 1753cc (107 cubic inch) engine intended for Harley’s top-of-the-range motorcycles.Information on the engine is still sketchy and largely confined to internet rumors, but it’s believed to be the recipient of the ‘Milwaukee-Eight’ name Harley trademarked two years ago with the ‘Eight’ referring to the number of valves.
While a Harley-Davidson with a four-valve-per-cylinder head design isn’t as radical an idea as it once was – after-all, the Harley-Davidson V-Rod has used eight valves for years – the Milwaukee-Eight design is far from conventional. In keeping with Harley-Davidson roots, the new engine doesn’t go in for those new-fangled overhead camshafts, instead sticking with the pushrods and rockers that are so intrinsically linked to the traditional cruiser scene.
Of course, operating eight valves via pushrods is a little more complex, and to achieve it Harley-Davidson is believed to have switched from two camshafts (one for each cylinder) to a three-camshaft design. This layout is similar to the one already used on Indian’s big V-twins, but the Harley-Davidson’s cylinder heads will be more complex to allow four valves to be fitted.
Pushrods and four-valve heads aren’t a common combination. That’s largely because engines with lots of small valves are usually designed to rev high, and as such are developed with peak power in mind rather than low-end torque. Pushrods lead to a heavy valve train that goes against this high-rev thinking.
There’s a suggestion that the new Harley engine has taken longer to develop than expected. Harley-Davidson first applied for trademarks in Europe and America on the ‘Milwaukee-Eight’ name back in June 2014. The dates imply of launching the engine as early as 2015 but delayed its introduction until the 2017 model year.Tag: Harley-Davidson Harley 107 Engine Development Business 2017 V-Twin 1753cc Pushrod Trademark Four-Valve Overhead-Camshaft Cylinder-Heads
