Powertronic Fuel X Autotune Pro+ Review: Himalayan 450

How does it work?

The Fuel X works in tandem with the motorcycle’s fuel injection system. According to Race Dynamics, maker of the device, it adapts to various parameters, including engine condition, wear and tear, riding style, and performance upgrades such as freer-flowing air filters or exhausts. Additionally, it factors in environmental conditions such as temperature, humidity, and altitude, to deliver a smoother, more potent ride.

Now, in a closed-loop fuel injection system, the ECU decides the amount of fuel going into the combustion chamber based on the oxygen levels detected by the O2 sensor. When the O2 sensor detects high oxygen levels in the exhaust manifold, the ECU responds by increasing fuel flow, resulting in a richer mixture. Conversely, low oxygen levels trigger a leaner mixture.

The Fuel X module acts as an intermediary between the O2 sensor and the ECU. Selecting a rich setting on the Pro tricks the ECU into believing that the oxygen levels are higher in the exhaust, prompting it to inject a richer mixture. Meanwhile, choosing one of the two lean settings convinces the ECU that the oxygen in the exhaust is lower, resulting in a leaner charge entering the combustion chamber.

The installation

Installing the Fuel X requires some effort. One has to remove the seats and the fuel tank to access the lambda or the O2 sensor connector. The Pro+ version comes with three main components:

- A main module that goes under the seat.

- A handlebar switch to change the settings.

- A wiring harness connecting the handlebar switch, O2 sensor and main module.

Additionally, there are zip ties, some stickers, and a quick start guide. On the Himalayan 450, you’ll also need to remove the toolkit from under the pillion seat to accommodate the Fuel X main module.

We recommend getting it installed at your friendly neighbourhood garage to save time and energy.

The ride experience

The Fuel X Autotune offers 10 AFR or Air Fuel Ratio settings to choose from. Setting one and two are lean, three mirrors the motorcycle’s stock setting, and four onwards the mixture gets richer. Since we had the option, we thought why not stay as far away from stock as possible and flirt mainly with the richer choices? So, we mostly stayed between eight and 10 for the course of this test. And in all three settings, within minutes of riding, five things stood out.

Firstly, the throttle response became more linear, and idling stabilised. And the motorcycle became significantly easier to ride under 3,000rpm.

Previously, the stock H450 struggled under 3,000rpm, requiring a delicate dance between the clutch and the throttle to get off the line cleanly. Ditto when it came to slow-speed riding, be it coming up a mall parking or taking on something slow and technical off-road. Not that the Fuel X has made the H450 as easy as pie to ride at slower speeds, but, it has definitely made it more natural and manageable.

One doesn’t need special skills to ride under 3,000rpm anymore. It has also reduced the need for constant gear changes. Now, the bike pulls with less hesitation from 2,000rpm instead of throwing tantrums. I am also shifting sooner because dropping under 3,000rpm isn't a challenge anymore.

The Himalayan is running cooler on our commutes as well. Cooler, mind you, not cool. While you can still feel the warmth of the engine creeping up to the thighs, it’s no longer uncomfortable. But then we are running the motorcycle on the richer AFR settings. Relatively more fuel in the combustion chamber does mean cooler running.

Lastly, engine braking decreased drastically, making the motorcycle almost freewheel at overrun. Although this is an uncomfortable feeling and takes some getting used to, it reduces stalling and allows the bike to chug along in first gear without any throttle input. This helps off-road as well.

This effect reduces significantly when you come down to setting four. And then in settings three to one, the motorcycle feels quite normal in the overrun. There’s decent engine braking to had even though the off-throttle transition goes back to being slightly choppy. Having said that, the Himalayan with Fuel X still remains easier to ride compared to one without even in settings one, two and three.

Should you buy one?

Let us first address the elephant in the room - if Fuel X can make the Himalayan 450’s fuelling friendlier, why doesn’t Royal Enfield offer it as standard from the factory? The answer lies in emissions. Royal Enfield has to meet the stringent BS6 Phase 2 standards to sell the bike which doesn’t allow RE to run richer AFR settings for better rideability or throttle response. Race Dynamics, maker of the Fuel X, however, is not bound by these regulations. After all, it clearly says on the box that Fuel X is intended for closed-circuit use.

So, should you buy one?

We think so. It transforms the Himalayan 450 into a friendlier motorcycle, making it easier to ride thanks to its progressive throttle response, more predictable fuelling, and a better spread of torque at lower rpm. Plus, the richer fuel mixture ensures cooler running and reduced engine wear. That said, the Pro + version however is a little on the expensive side. That’s the only downside we can think of, apart from the fact that you will lose your warranty once you plug it in.