Base stats:
– BTU:  15.800 (That…is…insane)
– Weight:  11.5 oz (including pump, not incl. bottle)
– Stove comparison chart

Leaving aside all the incredible details and features that the Soto Muka brings to bear, the most important thing to note, at the end of the day is:

If you want a liquid fuel stove that boils water incredibly fast, like full-32oz.-GSI-kettle-of-water-from-60F-to-rolling-boil-in-3.5-minutes-fast, we’re talking insane levels of heat output here, than the Soto Muka is just what you’ve been looking for.  (NOTE:  altitude below 1000 feet)

The Soto Muka is one amazing stove.

But while I’ve had the Soto Muka for some time, and have done a good amount of water boiling and cooking with it, it’s not really my goto stove on trips.  Mostly because while the engineering behind it is stunning, it’s incredible advantage in specialized scenarios is not something I really need, and it’s slight disadvantage in more common scenarios I find myself in makes me choose other stoves.

The Soto Muka is tailor made for a very specific scenario:  Boiling water and melting snow in cold and/or high altitude conditions.  The Soto Muka kicks out 15,800 BTU at the stove head.  That is more than double the heat output of denatured alcohol and almost 50% more than most other liquid fuel stoves.  The wider stove head means a wider super-heated hotspot, and the sheer speed with which it kicks out fuel forces the clean fuel up the sides of even 6” diameter pots (pictures further down).

In cold weather, that’s a good thing.  Rather, that’s a great thing.

Now, any stove will melt an aluminum pot if there’s not water in it.  But most often, being moderately careful without stressing out is not big deal. With the Soto Muka, a little more caution is required because that much heat means it can cause trouble that much more quickly.  Also placing too much weight on the stove, or the steel legs is not a great idea as the legs, softened by heat, will warp or maybe even buckle under, say, a 2+ liter pot or a small cast iron pan.

Great things about this stove:

• It’s very compact, one of only two liquid stoves I have that fits inside the Snow Peak mini cook set.  Not even the OmniLite fits in that set.  Now that’s compact (Photos at bottom)
• Pressure indicator.  spring loaded pressure indicator works reliably and consistently (pump until red line appears, that’s it)
• Wider hotspot.  This doesn’t matter much when boiling water, but it’s worth noting.
• Non traditional priming.  They mitigate the mess associated with priming, by using a dial to send liquid fuel to the stove head with air
• The air sent through to feed the fuel during priming improves the starting process dramatically, even in thinner air
• Dual intake pump is innovative, dial determines air flow
• Fuel connector is a very simple locking mechanism
• Burn unleaded fuel cleanly.  (This is rare!)
• quick lock connector
• The entire system can be used with gloves on (Great for cold weather)

Here are some quick negatives:

• It burns through fuel faster than other liquid fuel stoves.  A 700ml bottle (480ml of fuel) lasts about an hour on full blast.  “Simmer” doesn’t last that much longer.
• Speaking of simmer, it can’t.  Not…at…all….  For one, it only has a single throttle, but even compared to other single throttle liquid fuel stoves, this thing is bad at simmering.
• You have to pump a ton to get this up to recommended pressure.
• Legs are not super strong, 1.5L of water in an HA aluminum or titanium pot or less is safest.  Don’t use cast iron, don’t go passed 2L of water.
• The fuel line connection on the stove side is a potential weak point.
• No reinforcement brackets on the generator coil, making it very easy to break.

—

FEATURES:

The stove has some innovative engineering design components.

Let’s start with the pack list:  You get the stove, the pump, a bag with an inner pocket, a multi-tool, silicone grease, and a spare o-ring for the pump.  Pretty basic.

—

STOVE UNIT:

First, the stove head is convex, forming a little hill.  Normally, that would make it a little weak against wind.  But the stove is so forceful that it doesn’t get blown out easily, and unlike many other stoves, light breezes have very little effect.

At max output, the flame is so strong that I would not recommend using a Sea To Summit X-Pot or X-Kettle.  This stove will likely melt the silicone sides.  Above is the ubiquitous GSI Kettle.  You can see the flames moving up the sides.  It’s a little more dramatic in real life, but you get the idea.

The legs are interesting.  Rather than twisting around the stove like many other liquid and LPG stoves, the leg stands actually twist around the hinge so that the closed position has the legs inverted.  It’s effective in making the stove very compact when closed up.

Interestingly, Soto recommends changing the generator out every 200L or so.  A bit strange, but I guess it gets clogged up over time.  Still, that’s a lot of liters of fuels, and given that the 700ml bottle equates to 480ml of actual fuel, that amounts to about 400 refills.  If you used an entire bottle every weekend each year, that still translates to 4 years of usage.  If you’re a weekend backpacker like me, that really translates to about 12 refills a year….well….let’s just say that’s a lifetime use.

The hose attachment to the generator is very innovative.  Instead of being in a fixed position, it actually rotates a little and that’s pretty impressive.  It mitigates the chance of bending the fuel hose at the connection point, because that point moves with the angle of the hose.  Pretty ingenious design, really.  And I don’t have any other stove that does this.  It’s also an important one, because that fuel line is the thinnest, most flexible fuel line I’ve ever experienced, and without that connection point motion, I’d be very nervous in taking the Muka with me as the only stove I rely on.

—

THE PUMP SYSTEM.

The bottle is interesting.  It has a larger opening compared to other fuel bottles.  Given the rigidity of the pump’s plastic fuel lines, this is a good thing.  It also makes it easier to avoid spilling fuel when filling the bottle.

—

Which brings me to the pump.  While the Primus remains my absolute favorite pump system for its ingenious simplicity, the Soto Smart pump has superb engineering details and features.

The pump mechanism itself is among the smoothest systems i’ve experienced, and is very effective.  But not matter how effective, getting pressure up until the red line indicator shows is definitely a bit of work.

The Soto Smart Pump is the only pump system I know with independent fuel intake and air intake.  Pretty innovative.  What this means is that whereas other pumps require flipping the bottle to allow air through to clear the fuel line, the Soto Smart pump allows the bottle to remain in the same position, and instead, uses a dial to switch from the fuel intake line to the air intake line.  Pretty smart.  however, this does leave a little bit of fuel in the plastic fuel intake on the pump mechanism itself.  Not really a problem as the fuel won’t damage the plastic fuel line.  Both the fuel intake and air intake are plastic.  I generally don’t like plastic fuel lines in a pump system because I have some dissatisfied experiences with their rigidity.  Having said this, the plastic intakes on the Soto Muka are probably the most rigid I’ve ever seen on a pump.

The pumping handle is larger than other pumping handles, and the action is very smooth.  You can also tell from the photos that the complexity of the SmartPump features does make i bigger than other pump systems.

 

Another great feature is the simplicity with which the fuel line locks onto the pump.  Pull back the locking mechanism, insert (or remove) the fuel line connector, and release the locking mechanism.  That’s it.

  

There is a spring loaded pressure gauge indicator that shows a red strip when there is enough pressure in the bottle.

The dial is also very interesting. The dial, when engaged, has a number of settings.  The main position is “stop”.  This is the same as having the dial depressed.  Flow is completely cutoff.

Most fuel pumps just have a dial to determine flow.  But the Soto dial is much more high tech.  First, the dial can be engaged or disengaged.  Genius!  To disengage the dial, simply depress the dial flush against the pump housing.  To enable the dial, simply pull it up.  What this means is that there is no accidentally churning out fuel while it’s in your pack.  In the depressed position, turning the dial has no effect.  This safety mechanism is my favorite among all liquid fuel stoves and is a feature every fuel pump dial system should have.  In fact, even when in use, depressing the dial shuts off fuel, to quickly kill the flame.

Turning the dial counter clockwise, next up is “Start”.  This is the same as priming.  In this unique position, both the air intake and fuel intake are pushing through at the same time.  Be careful not to flip the stove at this point or fuel will spill.  As soon as you turn the dial to this position, have a fire starter ready (a lighter is probably best).  Be ready to relight a lighter as air is rushing through at the same time to help fuel the…well…fuel.  Because it’s sending air to work with the fuel, the start mode is fairly similar in strength to regular mode.  It also means the generator gets heated much faster than normal priming procedures.

So after 5-10 seconds, you’re ready to switch to regular fuel mode.  This mode stops sending air through, and only allows fuel to go through.  Note, however, that at this point, you will likely need to pump a few more strokes again as pressure will be reduced because of the amount of air that was sent through during “start” mode.  When in “run” mode….there is a range for stove usage, and it starts at max flame.  As you continue to turn the dial counter clockwise, it lowers, but….even at it’s lowest, the Soto Muka is still pushing flame out hot.

You absolutely cannot simmer with this stove.  I don’t care what anyone else says, as someone who has an irrational love of stoves and owns a fair number, trust me on this…this stove cannot, and was clearly never designed to simmer.  If you brought a separate pot stand, maybe make your own, you can set the pot another inch or two above the stove head, and this might give you simmer mode, but at that point, why not just get a different liquid fuel stove instead.  Nono.  This stove is designed to boil water fast, or to melt snow fast.  That is what you will use this stove for, and it will do that job better than almost every other stove on the market.

SIDEBAR:  In point of fact, because the starter mode (priming mode) pushing a lot of air through, this stove will prime faster at higher altitudes than other liquid fuel stoves.  Other liquid fuel stoves will be forced to work with the thinner air of higher altitudes only, but the Soto Muka will have additional air that is pushed out of the fuel bottle.

Passed the lowest flame setting, continuing to turn clockwise, will get you to “air” mode.  This is the pressure relief mode, and will simply send air pressure through the fuel line until all the pressure is released from the bottle.

That pretty much sums up the stove features.

—

One of the things I most care about with regards to stoves is how to pack it efficiently.  Generally, that means what cookset does the stove fit into.

The Soto Muka closes up is so compact that it fits in very tight spaces.  If you want a fast boiling liquid fuel stove that fits into small sets, this stove is for you.

It fits easily in the Snow Peak mini cook set, an impossible feat for every other stove except the Edelrid Hexon stove.  Even the tiny Primus Omnilite does not quite fit in the Hybrid cook set.  For reference, I’ve included the rather large Optimus Polaris Optifuel for comparison as well.

It also fits in the Snow Peak 700 Hybrid Summit, with plenty of room to spare.  The Primus Omnilite fits in nicely, but notice that it’s a pretty tight fit with little room for other knick knacks.

And of course, it fits in the GSI Halulite.  Because of the smaller size the of the GSI Halulite, and it’s toughness against strong heat, it’s actually not a bad fit for the Soto Muka.  If you’re trying to minimize trash produced by LPG stoves, the Soto Muka paired with the GSI Halulite would be an interesting combo.  Boils water in about a minute and change, so you’d get about 12 water boils out of it (for you quick calculators out there, I know that I said the bottle lasts about an hour, but remember that priming also uses fuel.  the one hour estimate is really if you use the stove almost continuously)

—

USAGE SCENARIO.

As already mentioned, the Soto Muka melts snow/ice and boils water in below freezing environments (also at high altitudes).  The challenges in below freezing temperatures or lower density air (or both) are very unique.  Here’s a video I found of using the Soto Muka in -40 degree weather (https://www.youtube.com/watch?v=AyD0gooCNM8)

Every feature:

• From pumping air with fuel during priming to prime faster at high altitudes,
• to burning unleaded gas cleanly and consistently,
• to utilizing a wide stove head (to maximize heated surface),
• to sending heat out incredibly rapidly,
• to simplifying fuel connections for freezing, shaking hands,
• to using a wide body dial to easily work the stove with globes on
• to incorporating a wide flat head pump handle and using freeze resistant silicone for the pump seal instead of the more common greased leather…

…absolutely every feature, seems to be designed for the specific scenario mentioned above.

WHY UNLEADED FUEL?:

You want to use a fuel that has a very low flash point.  There are very few fuels that have a below freezing flash point.  Unleaded Gas has a flash point around -45 degrees F, and LPG fuel cans have low flash points as well (n-butane:  -76F,  iso-butane:  -117F, Propane:  -156), though, there are other issues with LPG stoves in the winter, but that’s another review.  The more ubiquitous stove focused liquid fuels all have above freezing flash points:  White gas is around 44F, and Kerosene, jet fuel, diesel all have flash points above that.

Pure propane is too volatile in liquid form, and requires tremendous pressure to vaporize, so requires a very strong and heavy tank.  Not good for backpacking.  If you’re not already familiar, the super strong Colemna 1 gallon green tanks sold at Walmart and, well, everywhere are propane tanks.  LPG gas canisters work, as they mix these volatile fuels, but really are designed to work in warmer environments where you can fuel a stove flame using vapors.  At lower temperatures, the pressure in the canister is reduced, which reduces vapors.  the workaround is to use a stove that allows for liquid mode of these canisters, but this burns through fuel very quickly.  (It should be noted that depending on the mixture of n-butane, iso-butane, and n-propane, some cans word better in the cold than others).

So…in the end, unleaded is a great winter/high altitude choice in a liquid fuel stove….except for two problems.  First, unleaded is one of the dirtiest fuels to use.  To burn clean, the stove needs to be very hot, almost abnormally hot.  The Soto Muka solves that problem in spades with the wide head to better catch particulates and burn them.  Secondly, and unrelated to the Soto Muka, unleaded is more dangerous to store.  With such a low flash point, unleaded is extremely volatile.

Incidentally, the Soto Muka also works off the much safer White gas fuel (or naphtha fuel, or Coleman fuel).  White gas has a flash point around 44 degrees F, so, while not quite as safe as most type of kerosene to store (Kerosene ranges from 38-72F flash point depending on what type you get), it is much safer than unleaded.  And white gas has the benefit of burning cleaner than unleaded, and is also less toxic.  So, the Soto Muka can be an ultra fast water boiler for most backpacking trips, especially if producing trash with an LPG gas canister is something you’re trying to avoid.

—

Maybe the best feature focused review of the Soto Muka:  https://www.youtube.com/watch?v=kG9KXvUZbHE

The Soto Muka can do simple cooking, as long as you’re paying close attention.  But sauces will burn and stews and other slower cooking items are a bad fit for the Soto Muka.  Here’s a video i found of someone cooking a simple meal with the Soto Muka:  https://www.youtube.com/watch?v=4ukrhTd8cFI

Soto makes a range of LPG gas can stoves as well.  And it’s interesting to note that the Soto Windmaster is almost the exact opposite in capability when compared to the Soto Muka.  Among all the compact LPG stoves I own (and I own quite a few), the Soto Windmaster is the best at simmering, adding very unique features specifically for simmer control.  it will be interesting if the company can come up with products in the future that bring the best of both these stoves together.

—

BTW, like many Japanese manufacturers, only a select few of Soto’s products are sold in the US.  To see the full range of Soto Products available, go here:  http://www.shinfuji.co.jp/soto/products/st-9xx/

You can no longer purchase the Soto Muka through REI.  They stopped selling it in earlier this year.  However, you can still find it on ebay, and some Japanese online stores occasionally carry it.  Some examples are:
– fujisan.com
– bestfromjapan.com

—

Other reviews around the web:

• http://www.mikaelstrandberg.com/2012/09/27/gear-and-kit-review-soto-muka-stove/
• http://adventuresinstoving.blogspot.com/2012/02/soto-muka-stove-od-1np-full-review.html
• http://seattlebackpackersmagazine.com/the-soto-muka-stove-review/
• http://www.livefortheoutdoors.com/Gear-Reviews/Search-Results/Camping-stoves/Soto-Muka-2011/
• https://climbinggearreviewsuk.wordpress.com/2011/07/20/gear-news-the-muka-stove-from-soto/
• http://firelitetechsupport.blogspot.com/2012/02/the-soto-muka-stove-od-1np-review.html
• http://www.trailspace.com/blog/2011/01/23/outdoor-retailer-soto-muka-stove.html
• http://www.outdoorsmagic.com/forum/gear/soto-muka/49552.html
• http://thenextchallenge.org/soto-muka-multi-fuel-stove/
• http://seattlebackpackersmagazine.com/the-soto-muka-stove-review/

Video reviews:

• http://www.videomoviles.com/sSU_MTWPlJs/soto-muka-stove-od-1np-liquid-fuel-test-review-and-demo/
• http://fillable-rares.rhcloud.com/expand/soto-muka-multifuel-camping-stove-review-the-next-/
• http://www.trailspace.com/blog/2011/01/23/outdoor-retailer-soto-muka-stove.html