Colove

Colove brings back the 400 cc four
By Ben Purvis

Even among the hordes of upstart Chinese bike brands, Colove is a relative newcomer. However, it's one that is showing a huge amount of ambition by demonstrating a new 400 cc four-cylinder engine that's destined for a baby sports bike in the near future.
Colove, which also uses 'Kove' branding and sells its bikes under the 'Excelle' name, presented the new four-cylinder at a press demonstration earlier this year - as well as showing design drawings for the machine that will use the engine. Not only was the engine shown, but it was started and revved on stage, with the company's president stating that it's an entirely in-house design. He even pledged that if anyone could prove it was a clone of another company's design, he'd personally eat the engine!

While 400 cc fours were commonplace in Japan in the 1980s and early 90s, the format has always been relatively expensive to build, and they've fallen from favour in recent years. A high-revving 400 cc four has as many components and needs to use the same high-tech materials as a superbike's 1000 cc four, so they aren't much less expensive to manufacture. Also, European emissions rules, with a focus on hydrocarbon emissions, don't favour high-revving engines - they require a lot of valve overlap to fill and empty the cylinders efficiently at high rpms, which in turn can allow unburnt fuel into the exhaust when they're not revving high.
Colove's engine, measuring 399 cc, has a wide 59 mm bore and short 36.5 mm stroke that lends it to high revs - the redline being set at 16,000 rpm. Peak power is claimed to be 72.4 hp at 13,500 rpm, with 32.4 lb-ft of torque arriving at 12,000 rpm. Unlike the old generation of Japanese 400 fours, it's fuel injected to help meet emissions limits.

The design sketches for the bike it will appear in, the 400RR, reveal it to be a trellis framed, full-faired sports machine with a hint of Ducati in its styling, which includes features such as a single-sided swingarm and side-mounted winglets as well as a large, central air intake to feed the screaming engine.
While only presented as a drawing so far, Colove says the bike will weigh less than 160 kg and hit a top speed north of 220 km/h (135 mph).
The development of a totally new four cylinder isn't the only challenge on the company's agenda, as it's also creating a whole range of 800 cc parallel twin models, all built around an engine that looks suspiciously like the KTM LC8c design that's built in China by rival CFMoto.