/‘Twins FT’: A Royal Enfield x Harris flat tracker

‘Twins FT’: A Royal Enfield x Harris flat tracker

A Royal Enfield flat tracker from Harris Performance
Four years ago Eicher Motors, the owner of Royal Enfield, bought the famous British company Harris Performance. Since the 1970s, Harris has been building high-performance ‘specials,’ and the Hertfordshire firm had already developed the chassis for the Continental GT and Himalayan.

Harris has now gone back to its racing roots with this very intriguing prototype flat track racer based on the 650 twin engine.

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
It’s a collaboration with Royal Enfield’s technical center in Leicestershire, and although it’s essentially a custom project, we’re wondering if it could also herald the start of a flat track race program.

“Inside Royal Enfield, we like to have a bit of fun,” says RE’s industrial design boss Adrian Sellers. “So we’ve started working on ‘Factory’ builds, to push the limits of our motorcycles’ capabilities.”

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
“To date, these have included a record breaking Bonneville Salt Flats racer, two drag bikes, two retro racers and now this new ‘Twins FT’ flat tracker.”

The tracker is probably the most ambitious build yet. Harris has over 40 years of expertise in chassis development, but this is the first time they’ve built a flat track chassis.

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
The frame is brazed steel tube—an old-school technique applied to a thoroughly modern motorcycle. The steering stem angle can be altered two degrees each way, by using specially machined inserts that locate the stem bearings at a different angle within the headstock tube.

The yokes can be adjusted 4 mm forwards and backwards too, and the swingarm pivot height has 5 mm of adjustment both ways.

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
“These adjustments can be used to fine tune the chassis,” Adrian says, “altering the stability of the bike, how it turns in, and how it behaves under power.”

“As this is an exploration, Harris designed-in quite a wide scope for adjustment. As the chassis is developed with more testing, this adjustability could be decreased—to reduce costs and component size.”

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
All the other chassis parts have been developed specifically for this bike by Harris, including the front forks, which are 41mm right-side-ups running Öhlins 30mm valving.

They’re matched to a top-of-the-range Öhlins TTX36 shock, and the 19-inch wheels are RSD Traction race rims—CNC machined from forged billet aluminum. The tires are the ubiquitous Dunlop DTRs, and there’s obviously no front brake. The rear wheel is hooked up to a Brembo twin-piston setup.

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
The motor has been juiced up by
S&S Cycle, who helped with development of the 650 twin. The American company has supplied the exhaust system, a 750cc big bore kit, and a custom ECU mapped to make the best of both upgrades.

It was the UK design team at Royal Enfield’s technical center who made the stylish carbon bodywork though, taking cues from existing flat track practices.

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
“As much as we wanted it to look good, we also wanted function to take precedence,” says Adrian. “So Harris made a working chassis first, and then our team designed a good-looking body based on that.”

The bodywork was modeled in 3D, and a negative mold was milled directly into high-density foam. The carbon has been laid up directly into that. Royal Enfield’s in-house modeler made the molds, and the carbon was laid up by Scorpion Composites and P3 Composites.

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
“Once you’ve designed a few motorcycles, you can visualize the final surface from the CAD,” says Adrian, “and be confident in outputting it directly—without going through a physical modeling step.”

The fuel tank is a separate aluminum vessel that sits below the body shell. “This allows us to change the volume of the tank in the future, without affecting the aesthetics.”

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
There’s some smart thinking going on here, and we reckon Royal Enfield have nailed the looks too. The bike has already been spotted running laps at a speedway track near RE’s British headquarters, and S&S could probably deliver a decent power output—given that they are heavily involved with Indian’s all-conquering FTR 750. But Adrian is coy about the competitive future.

“We’ve done a little testing to see if we’re in the right ball park, and we are, but not much more than that,” he tells us. “We’ll see how further testing goes, and take it from there. We wouldn’t want to go out unless we have something competitive, and racing is an all-new activity for us—so there is a lot of learning to be done.”

A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance
We’re even more excited about a potential roadgoing version, given RE’s known desire to expand the 650 line-up, but there’s no word on that.

Still, if you’re in Milan for the upcoming EICMA show, swing by the Royal Enfield stand to check out ‘Twins FT’ in the metal—it’s a must-see.

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A Royal Enfield flat tracker from Harris Performance
A Royal Enfield flat tracker from Harris Performance

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