Soto Muka Stove
This small, lightweight, liquid fuel (not multi-fuel) stove is perfect for those who are motorcycle touring, or travelling to places where butane gas canisters are not so readily available. A nifty little stove that encompasses a number of technologies I expect to see in many more stoves in the future.
My Feedback and review:
One dark and stormy December afternoon in Brisbane, 2014. A shadow of a woman appeared in the door, accompanied by the sound of driving rain, and thunderous applause from the gods. The regular flashes of lightning fleetingly illuminated her face, revealing a menacing figure. A former colleague, who had long since left us. Concealed in a small bag she carried an object of huge power, one that she claimed would change me forever. At least given the drama of the damaging hailstorm the previous week, this narrative seems appropriate.
The shadowy former colleague is actually our not-quite-so-shadowy rep for Sea To Summit. The storm was real. She had brought with her one of her company’s latest acquisitions, the Soto Muka stove. I was impressed. I ordered a few in for the store, and bought one myself. This stove landed promising to fundamentally change the way we think of liquid fuel stoves, and I can't say that after using it I find myself protesting this claim too much.
When I think of Liquid fuel stoves, my mind immediately recalls the mildly irritating, sooty, and occasionally unexpectedly thrilling business of preheating, or "priming" these creatures. In previous stoves, fuel at a relatively low pressure is fed into a hot "Generator" tube, which vaporises the fuel. The vapour is then mixed with air and finally supplied to the burner where it burns cleanly. The need for priming stems from the necessity to preheat the generator to the point where it vaporises the fuel. No longer!
The Muka avoids this process entirely. On start up the Muka pre mixes air and fuel in the fuel line, by way of their cleaver pump design, which is then delivered at much higher pressure to an atomiser. The atomiser creates a fuel rich vapour cloud which readily ignites, and burns much more cleanly than liquid fuel in a priming pan. Because the vapour cloud burns much more completely than liquid fuel, there is no soot left over. Clean! After a few seconds the flame produced by the Muka settles down to a familiar blue cooking flame, and you move the control knob to "Run". Done. It works a treat, and is very easy to use, despite my initial concerns, and visions of giant fireballs.
So that cleaver pump design; This is no pump and simple throttle affair, and I'm very impressed. A pressure gauge signals when the bottle is up to pressure. A small pin pushes out as the pressure increases, revealing a red band when fully pressured. There is an emergency stop feature on the control knob, operated as a simple "Big Red Button" device ... only not red. The control knob has four settings: "Start", "Run", "Air", and "Stop". The "Air" setting, expels compressed air from the fuel bottle through the fuel line, cleaning the line, extinguishing the flame, and de-pressurising the fuel bottle without the spray of fuel. Brilliant! ... but big. It does not fit into any fuel bottles other than the ones Soto had to build for it.
The mouth on the bespoke fuel bottle is significantly wider than on other models. The claim is, it is easier to fill without spilling. I suspect a marketing team had a look at the wider mouth needed to accommodate their fancy new pump, and saw an opportunity to turn design necessity into ergonomic gold... but that doesn't stop it being true.
Speaking of pumps. The higher pressure in the bottle needed to start the Muka does require a lot of pumping. The rep stood in-front of me for several minutes pumping the thing during the demonstration she gave me. According to Soto, and I've not counted but having done it several time I believe it, it takes 70 strokes of the pump to bring a FULL fuel bottle up to pressure. My MSR takes 10-15 strokes.
A small city car is smaller, lighter, and cheaper than a big four-wheel drive, there is no real news there. The Dragonfly is a true multi fuel stove, equally capable of running on shellite, unleaded petrol, kerosene, or diesel. The Muka runs on shellite and unleaded petrol only. When I asked if Kerosene was not recommended, or simply incompatible, Hailey responded "Just don't". The Dragonfly also excels at simmering. Though some claim it does OK I find this something the Muka has trouble doing.
So apples with apples shall we, or at least city cars with city cars. The Muka's true competition is MSR's Whisperlite series. These stoves have stood the test of time, having been around without major redesign for the better part of three decades. I have a Whisperlite International, which I am quite fond of, and it really has been a bit of a work horse for many adventurers. So how does the Muka really stack up?
First up, price. The Whisperlite is essentially the same price as the Muka, coupled with its hard won reputation many will see the Whisperlite as the wisest option. The logic is hard to argue, but the Muka has many charms of its own, and reputations take time to nurture.
Walkers, cycle tourers, mountaineers, and adventures of all creeds are renowned sticklers for weight. With stoves though, the headline weight figures don't really tell the whole story. At first glance the Muka is strikingly light, 164g minimum weight compared to 305g minimum weight of the Whisperlite. However, the Muka's pump weighs as much as the stove itself. Even so, the Muka sits in the pack at 333g, still 80g lighter than the Whisperlite at 410g.
The Muka is more compact than the Whisperlite, and the very flexible fuel line makes it easier to stow in smaller cookware. The Muka appears less robust than Whisperlite, not fragile, but in need of attentive packing. I have no concerns recklessly hurling my Whisperlite into my pack, but the folding leg assembly on the Muka feels like it's easier to damage.
Comparatively the Muka is thirstier than a fresher in O-week, and I was a little worried that I may need to carry extra fuel compared to the MSR. A 700ml fuel bottle filled to its max fill level, will supposedly keep the Muka purring along for about an hour on full throttle, and for an hour and a half on minimum. The Whisperlite on the other hand claims 136 minutes from a full bottle. The issue is exacerbated by the fact that the Soto fuel bottle, though a similar size to the MSR, has a very low high tide mark.
The large pump on the Muka takes up space in the bottle, and reduces the volume of fuel which can be carried. In the 700ml Soto fuel bottle, this means that the safe fill line is at a disappointing 480ml. Compare this to the similar sized MSR fuel bottle, which can hold 590ml at its max fill. A thirsty stove running on a half empty bottle had me worried, so I boiled some water.
Some rough calculations utilising spherical chickens in a vacuum (only without the analytical rigour), suggest that it takes each stove around the same volume of fuel to boil a litre of water. This is mostly due to the fact that, though the Muka is thirsty, it is a much hotter flame so it takes less time to heat up. I would like to see Soto publish some “boil time” stats (as MSR, and others do) for a proper comparison with other stoves, but am reasonably satisfied that fuel consumption is comparable.
In other words, the Whisperlite will boil a few extra litres than the Muka, on a single bottle. Not a big issue really, but means there will be trips where one full MSR bottle will do, but you would have to carry extra fuel for the Muka.
How do you sum up a review like this?
Yes, it costs a little more, but offers a commensurate increase in functionality, and is a joy to use. The design of the pump makes the Muka a much simpler stove to use, and, despite a near miss during a demonstration, much less prone to unexpected excitement. I really like the inclusion of an emergency stop button, and the "Air" function to clean the system is a nice touch. Yes, it is lighter, but by a gnats wing in the scheme of things, the real story is that it is smaller, and packs more easily. It does take more pumping, but I got used to that pretty quickly, and the pump design really is one I see being a part of more stoves in the future. My only concern lies with the complexity of the thing. I know I can repair almost any issue with my Whisperlite wherever I happen to be when it occurs. I'm not so sure with the Muka, so I won't get rid of my MSR just yet.
K2 Base Camp