John Ellwood, creator of the two-stroke-four-stroke motorcycle engine, is still hard at work and is nearly finished with a motorcycle project that is over ten years in the making. Back in 2011, we covered Ellwood’s story, and at that time we learned that he was building a 1300cc racing bike. He had already been working on the project for three years, so it’s clear that things have spiraled a bit.
In October 2019, Ellwood posted an update in the Innovative, Banned, and Unique Racing Cars and Trucks Facebook group saying that he’s nearly ready to start his 1170cc crankcase supercharged single-cylinder engine. He notes that it’ll be a single speed bike with no room for a gearbox, and that the clutch is set into the swingarm. More impressively, Ellwood didn’t just design the engine, he engineered the entire bike around it. Despite the fact that it was made by a guy in a garage in Sweden, it actually looks like a coherent and usable bike.
In an interview with The Asphalt Junkie a few years back, he mentions being able to get a pass to run a larger 1300cc bike in Supermono road racing competition, which usually has a limit of 800cc. Though the 1170cc is an evolution of that project, Ellwood believes it will draw a ban from competition once it’s finished, despite the pass. It’s unclear how much power the engine will develop on ethanol or nitro/methanol, but his estimates for the original 1300cc were around 150 hp on ethanol and 400 hp nitro/methanol.
Ellwood’s motorcycles are as functional as they are funky and unconventional. In the Facebook conversation, he mentions wishing he had the funding to run the new bike at Bonneville. Assuming it’s not banned outright, Ellwood’s goal is to take the bike on its maiden run at the Flying Kilometer on Ice in Sweden next March.