First Impressions – Surface 604 Boar E350, Yep, It Is An Electric Fat-bike


Our time with the Surface 604 Boar E350, the first eBike we’ve had in for testing here at, began for us out at Interbike 2015 where we were thinking about doing a piece on the eFatbikes of Interbike. I took a bunch of photos of what were, essentially, converted standard fat-bikes. Frankly, while we took a bunch of photos, most of them looked pretty “backyard” and I did’t get much info on them so instead of just slapping up a bunch of photos I scrapped the article.

Among all the pretenders, we came upon the Surface 604 Boar. Wow! An electric-assist fat-bike that actually looks like a real bike. That simple fact was enough to draw us into the booth for a conversation that focused not only on the bike but the philosophy of replacing a car with a bike for everyday transportation. The Boar at Interbike was well equipped with fenders, front and rear rack as well as a Surly Bill cargo trailer. The whole setup retailed for under $4,000 and the electric-assist seemed like a cool compliment to the cargo carrying capabilities.

While our time with the Boar began with an introduction at Interbike, the Surface 604 company has been around for a few years. Surface 604’s first-generation eFat-bike was like several of the others we’d seen at interbike, a rear hub power unit with the battery carried on a rear rack. Not a bad start but the folks at Surface 604 have taken design up a notch with the second-generation Boar. It is clear that the power system is completely integrated into the bike. The most obvious feature being the custom designed frame that accommodates the 36-volt / 478 watt hour Lithium Ion batteries from Samsung.


We actually got in one of the show bikes, a Large, green version, for testing and it came to us fully equipped with the Boar-specific front and rear aluminum racks as well as custom aluminum fenders that will cover up to a 5.0-class fat-bike tire.

Since this is a Large, and I usually ride a Medium, I made a few cockpit adjustments to accommodate my 5’9” height. Changes included a shorter stem, a non-setback seatpost and a saddle swap to a Brooks Cambium C15 that has more fore aft adjustment than the standard saddle. With these changes I got it relatively comfortable but I wouldn’t suggest the Large for anyone under 5’10”.

About that power system. This is a pedal-assist bike. There is no throttle. The motor simply senses torque and adds power to your normal pedal stroke. With the power coming from the rear hub through a Bafang unit designed for fat-bikes, Tthe version we have is the more powerful 350w version. There is also a 250w version available depending on local eBike laws. One thing I learned while researching the hub a bit more is that it will deliver a peak of 750w briefly when you start riding. The 350w rating is a continuous output.

My first ride I didn’t turn on the power for a bit just to see how the Boar rides as a normal bike. Actually, pretty well. The close to 60-pound weight is a bit noticeable but the drivetrain is a straight forward SRAM X5 1X10 shifter/derailleur and it works exactly as you’d expect.

The brakes are Trektro Auriga hydraulic discs and, again, they work as expected providing well modulated stopping power.


Back to that first ride and its time to turn on the power system. There is a button on the top of the battery, right above a 4-LED charge level indicator, that you need to turn on first and there is a system power button on the left control unit that sits right about where a traditional front shifter would sit. The dashboard lights up and presents you with different info about the power system, a large speedometer and an odometer also fill the dashboard. For the first ride I was most interested in how much assist I’d be getting and this is a row numbered 1 to 5 that indicates the level of assist.

To get a feel for the assist I started out at #1 and felt a gentle “helping hand” pushing me along. Frankly, it felt pretty much like I was going about the same speed I’d be going on my APe for the same amount of pedal effort basically making up for the added weight of the power system.

I spent a few minutes in each of the 5 different assist levels. On both 4 and 5 I was pretty easily able to max out the bike at just above 20 miles and hour where the power system electronically limited my top speed. Remember, this s a pedal assist, not a throttle, so adding more leg power will make you go faster up to that electronic limit. The only way I was able to get more speed was to point the Boar downhill!

My first day with the Boar turned out to be a pretty long one and covered over 40 miles with probably 15 of that in a group ride where I did’t use the power at all. But, with the 11-mile ride home coming after 1AM and a stiff 20-plus mile-an-hour headwind I was very happy to have the power assist helping me on my way. That 11-mile ride would normally have taken close to an hour, probably more with the headwind and on maximum assist I was able to cover the distance in a bit over 30 minutes. Pretty cool when I was a tired human being!

Charging the battery is straight forward with the included charging unit and the battery has a retention system to keep it locked to the frame. A key is required to remove the battery to charge and I keep the key right by the charger because I’m prone to misplacing things!

Besides getting the cockpit to fit the only other modification I’ve made to the stock Boar E350 is to swap our the stock 30-TPI Kenda Juggernauts for a set of Dillinger 5’s that will be studded up as soon as the weather warrants it. Note that if you want to go with a larger tire right away there is an optional 100mm rim and 4.5″ Kenda Juggernaut Sport upgrade available at the time of ordering.

There are currently 2 sizes of the Boar E350, Large that I feel will comfortably fit folks up to 6’3” or 6’4” and a Medium that I would like to give a try at some point because I think that it would be a better fit for me right out of the box.


I’ve got over 200 miles on the Boar now mostly and while it is not the first electric bike I’ve ridden I think it represents, at least to me, a viable solution for urban transportation and light trail duty if your area allows it. I think that for more aggressive singletrack the extra weight is a liability and I would rather use a more agile machine. That being said, I think some folks may make the trade off depending on their own circumstances.

If you think that eBikes aren’t here for good, I’d reconsider! Heck, even the Sea Otter Classic, the largest cycling event in the world, has an electric MTB race planned for the 2016 event coming up!

We will be spending more time on the Boar once the snow flies here in Wisconsin. I mentioned the addition of the Dilly 5s and one of my plans is to use the Boar for trail grooming on our local trails when we finally get some snow! I’ll have another report down the trail.

How can you get one?  Head over to where you can learn more about the Boar, check out specs and learn how to order one of your own.

About Greg Smith 1127 Articles
Greg Smith, known to many site visitors as Sven Hammer, founded in 2011 and the site quickly became the #1 online community for all things Fat. You can currently find Greg outfitting Everyday Cycles; a Milwaukee, WI retailer of gear for fatbikers, adventure cyclists and urban assault riders.


  1. I test rode a Boar at my LBS parking lot. They sent me out on level 5. I couldn’t believe the torque when the assist kicked in. I likened it to smoking the tires on the General Lee while wearing a mullet, fun bike. Look forward to more review and see how it works as a trail groomer.

  2. Awesome. Now please change the website name to Just because it is electric powered doesn’t mean anything- it still has a motor on it.

    • All you nasty naysayers, go back to yo mama’s basements where you belong. You should be grateful that you are able to ride your bikes without assistance. In the blink of an eye, something could happen to you so that you will no longer be able to do so and then you can stay at home and make comments while the “able” are riding their bikes.

  3. I purchased the first running of the Sondors eBike. It of course has inexpensive components. This helped the $500 price tag + the $200 shipping. The first thing to go were the 4.8″ tires with some from Surly, Black Floyd. I’m a daily commuter with light trail use.

    Given the price, it’s a very good deal. If and when parts begin to fail, then I will replace with better quality components.

    I stopped riding my daily Salsa commuter because this Sondors eBike is much easier on my cartilage lacking knees and bone spur ankles.

    The 2nd generation comes available with front shocks, narrower wheel (still fat) and aluminum frame.

    I suggest the Sondors a try.

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