2024 SMRFS Defender Review

The Defender is purpose built for RV owners! It features an electronic anti-theft device with a loud alarm, is fully rust-proof and highly water resistant, and it's a very versatile e-bike that will perform well in just about any riding situation. Tackle off-road trails with the large (but still nimble) tires and suspension fork. Run errands in town with a rear rack, fenders, and integrated lighting. With an upgraded pedaling drivetrain and responsive torque sensor, the Defender is a ton of fun to ride and it's also adjustable to fit a fairly wide range of rider sizes.

Video Review

Written Review

SMRFS is a new brand in the electric bike space, but I wouldn't have guessed that from the quality of their Defender electric bike. It's actually a prototype; I'm reviewing it in part to provide feedback to their design team and help them get it dialed in for production. I've reviewed other prototype bikes before and they're usually pretty bad, so I was seriously surprised with how polished the Defender is. Sure, there are a few things that tell me it's not production ready - there wasn't an assembly manual in the box, and the frame has an extra non-functional charge port - but overall, the Defender is an excellent e-bike and there's just a few minor things I would change about it.

What actually makes an electric bike good for RV owners? SMRFS says: Water/rust resistance, anti-theft, and lifting assistance

It's no secret that e-bikes are increasingly popular in the RV community. They're fun to ride, and beat the heck out of towing your car around (or paying high prices to rent one). This has led to every e-bike manufacturer pretending their bikes are "great for RVers", but most of them aren't really. Technically, any e-bike works; throw it on a rack or fold it up inside, ride it around at the campground, and you're doing the thing. However, there are a lot of little details that can make or break your RV e-bike experience. Let's run through the important areas that SMRFS has focused on.

Risk of Theft.

E-bikes are popular targets for thieves due to their high value. Having to constantly worry about theft can take the fun right out of an RV trip! Whether you are leaving it on your rack or parking it somewhere while out on a ride, feeling that it is secure is crucial. The Defender has built-in anti-theft measures, with loud alarms triggered by motion sensors that are activated with a small key fob remote.

Exposure to the Elements.

Most people will store their e-bike on a rack behind their RV or camper; it's just so much easier than trying to store it inside, unless you have a folding bike (which presents its own problems covered below). Of course, outside storage means it's constantly exposed to the elements, and harsh weather can really do a number on most e-bikes. The Defender is completely rust-proof and has excellent water resistance of IPX6. That means it's able to withstand high pressure jets of water from any angle... for comparison, most e-bikes can only handle puddles or soft sprays of water (IPX 4 or 5).

Too Heavy / Difficult to Mount on Rack.

Fat tire e-bikes are all the rage right now but they're also very, very heavy, typically weighing between 80 and 100 pounds. Even the average smaller city-style e-bike will probably weigh at least 50, which is a lot of awkwardly-shaped weight to heft up onto a bike rack. The Defender addresses this issue in two ways:

1. It's rocking 3" wide tires, which provide similar float and go-anywhere traction to full fat tires, but they're much lighter weight. That's how the Defender manages to be a full-size adventure e-bike but only weigh 67 pounds.
2. It includes a bike rack with an electronic lifting system built in. Sadly, I wasn't able to test this as it isn't quite ready yet, but the concept is perfect; a bike rack for the rear of your RV that can electronically raise and lower, so you can just roll the Defender onto it as opposed to lifting it.

Here's why I think it's great for RVs: It's full-size, amazingly fun to ride, and can go pretty much anywhere

I never liked folding bikes for RV use; they just aren't as comfortable to ride as a full-size bike. They make sense if you're truly limited on storage space, but otherwise do yourself a favor and get something full-size. that's a big part of why I love the Defender; it's big enough that my 6'3" frame feels just right with the saddle extended to maximum height. Don't worry, both the saddle and the stem have a good range of adjustability so most riders should be able to ride comfortably, though it might be a little to much bike for anyone shorter than 5'4". It's size means you can sit and pedal comfortably, and go out for long rides without your back and neck getting sore, or your knees starting to hurt.

Let's talk about "fun to ride" factor. Pedaling actually feels pretty good on the Defender thanks to the upgraded drivetrain; it's rocking a Shimano Altus derailleur, and has a larger-than-average rear cassette with a 12-32 tooth range. What that means is you've got seven gears with a wide range of gear ratios, so first gear is great for climbing inclines and seventh gear is great for high-speed cruising. I actually didn't get into seventh gear yet because the maximum speed of the motor is 25 mph, and sixth gear works just fine for it. Speaking of the motor: for the most part, the electronic system on the Defender is a lot of fun.

• The 750 watt motor is plenty powerful, though I do think they should unlock it to 28 mph so it's a true Class 3.
• The best part is the torque sensor for activating pedal assist; it's amazingly responsive and just feels awesome.
• The throttle, unfortunately, isn't great. Its top speed is limited by your PAS level, which means the two assist modes don't play nicely. A throttle should give full power override in any assist level (more on this in the "what I would change" section below).

Last, let's discuss the "go anywhere" nature of the Defender. Again, I love the tire size choice! 26x3 inch tires are perfect for this kind of e-bike. They provide great traction for any terrain, a good volume of air for smoothing out the ride, and yet they're small enough to feel light and nimble, really awesome on trails. Plus you've got the upgraded suspension fork; sure, it's just a spring fork, but it's got a sizeable 100mm of travel, with preload and hydraulic lockout. It is perfect for any trail riding short of actual downhill mountain biking. The Defender is also equipped for riding on city streets and just about anywhere else thanks to all the included accessories:

• Full coverage plastic fenders for riding in any weather
• Integrated lights with brake activation, turn signals, and a flick bell
• Bright display that's easy to see in direct sunlight
• Sturdy rear rack with a 55 lb weight capacity

SMRFS will also offer a dual-battery option if the standard battery isn't enough, but with 30 to 60 miles of range depending on how you ride, I imagine the standard pack will be plenty for most people. Being in the saddle for more than 20 miles is tougher than you might think!

There's a few things I would change about the Defender: Top speed, throttle programming, and more visibility + puncture protection for the tires

Overall the Defender is an excellent e-bike, both for RVers and for just about anyone who wants a quality adventure machine. There are, however, just a few things I would like to see improved.

Top speed should be 28 mph on pedal assist, 20 mph on throttle. That would make it a true Class 2/3 electric bike, keeping with the most common legal regulations. It is possible to increase the top speed setting in the display, but even though I raised mine to 37 mph I still wasn't able to get past 25 mph before the motor seemed to cut off completely.

The throttle should provide full-power override at all times, regardless of PAS level. On a bike like the Defender with a responsive torque sensor, pedaling is the primary mode of riding. It feels great to ride, you get exercise, and you're going to get a lot more range. Thus, the throttle is just a complimentary system, mostly used for two use cases: getting started from a dead stop, and mid-ride acceleration for passing someone or for avoiding a collision. Riding the Defender in PAS 1 actually feels great; just a little bit of assistance, so you feel fast but still get exercise. But PAS 1 limits the throttle top speed to a paltry 6mph, which means it's useless once you're cruising. Consider this scenario: You're riding along at 15 mph in PAS 1. You see a car coming too fast from a side street, so you instinctively hit the throttle for a burst of speed to avoid being hit. But since you're in PAS 1, the throttle doesn't help... and actually, it makes things worse by cutting off the small amount of assist you were already getting from the PAS system. The throttle does override the PAS system, but since it's speed-capped based on the PAS setting, it becomes very frustrating to use mid-ride, sometimes even dangerous. This configuration requires you to fiddle with the display controls to increase your assist level to 4 or 5 before you can use it for extra acceleration, and then you have to turn it back down after since those high levels of assist are a bit too peppy for most riding situations.

The tires need reflective sidewall stripes for better side visibility. The Defender is a very dark bike and is hard to see from the side, especially at night; Yes, the front and rear lights have side cutouts which helps, but they're too easy to miss. I'd also like to see some puncture protection included by default, because it's a requirement if you're going to be doing any off-road adventuring. Yes, you can add your own (I recommend Tannus Armor inserts) but some sort of puncture resistance should really be included since literally everyone is going to want and need it.

Closing Thoughts: An excellent purpose-built RVers e-bike

The SMRFS team has done a solid job with their Defender series. It addresses the main complaints RV owners have about other electric bikes, and provides a satisfying and fitness-improving means of "last mile" transportation that makes it possible to tour the country without needing to bring along or rent another vehicle. Plus, the electronic lifting rack is a great touch! I'm excited to see further improvements to the Defender and would love to hear from RV owners about it. Do you own an RV? Chime in down in the comments section and let me know what you think!