2017 Surly Karate Monkey
Size Tested: Medium
- Drivetrain: Sram NX
- Brakes: SRAM Level
- Fork: Surly CroMoly
- Wheels: Salsa Hubs / Alex MD40 rims
Blister’s Measured Weight: 32.3 lbs (14.65 kg) without pedals
Reviewer: 5’9”, 155 lbs.
Test Location: Boulder City, Nevada
I rode the Karate Monkey at Interbike’s outdoor demo, which is located at Bootleg Canyon in Boulder City, Nevada. While people like to shun Vegas, the Bootleg trails are a little oasis of awesomeness in a land that’s otherwise dominated by neon excess. Bootleg has a mix of fast, sandy flow, and rocky cheese-grater gnarliness that’s plenty technical. If you haven’t been, Bootleg is a worthy stop on any southwestern road trip.
Normally this is where I go into talking about how a quick ride at a demo isn’t enough to get the complete picture of a bike because of suspension setup, etc. But the Karate Monkey doesn’t have any suspension, so there’s that.
But still, this was a relatively short ride on the bike, and we only got to ride in one very particular type of conditions. So with that in mind, let’s take a look at the Surly Karate Monkey.
The Surly Karate Monkey has been around for roughly forever, and it was one of the first “aggressive” 29ers on the market. The definition of what constitutes an aggressive 29er has perhaps changed a bit over the years, but this year, the Karate Monkey got a full redesign. The geometry has caught up with modern trends, various bits have been tweaked to accept modern components, and it’s designed to fit both 27.5+ and 29” wheels.
Of all the bikes we rode at Interbike, the Karate Monkey is clearly the outlier. It’s the only non-full-suspension bike we rode. It’s the heaviest bike we rode. It has the biggest tires of any bike we rode. And it’s the least expensive bike we rode by a healthy margin.
But was it the most fun? That depends on what cup of tea you like.
The Karate Monkey can be purchased as a frameset (with the rigid Surly fork), as a singlespeed, or as the complete bike that we rode.
The complete build has a no-frills kit that works well without breaking the bank. The Sram NX drivetrain shifted well, and the Sunrace cassette gives a decent gearing range while saving some money (and it avoids using an XD hub driver).
We haven’t spent a ton of time on the Sram Level brakes yet, but they seem to work well. They perhaps don’t have quite the power of the Guides, but for a bike like the Karate Monkey, they get the job done just fine.
The stock build doesn’t come with a dropper post, but the frame does accept stealth routing for one. Other frame highlights are a metric shitload of bottle mounts, and Surly’s clever “gnot-boost” 145 mm rear hub spacing. Basically, this is a steel frame, so you just bend or spread it to fit whatever size hub you want.
The stock Karate Monkey that we rode was rolling on 27.5+ wheels mounted up with Surly Dirt Wizard 27.5 x 3.0 tires. That’s some pretty meaty rubber, with an aggressive tread pattern and a reinforced sidewall.
Fit and Geometry
The Karate Monkey’s fit is right in line with most modern trail bikes; a 427 mm reach on a size Medium is middle of the road these days, and allows for some fore-aft movement without making the bike overly stretched out.
A moderately slack 73° seat tube angle works well on a hardtail like this, and it gives the Karate Monkey a long-ish 610 mm effective top tube length in the medium size.
Those numbers add up to a bike that feels pretty middle of the road in terms of sizing. At 5’9” with a 32” inseam, I was comfortable on the Medium, and that’s definitely the size I’d go with. Surly has a sizing chart here that generally seems about right, but for people with “average” proportions, I’d bump up to a larger size quicker than they do. For example, I’d definitely recommend that someone that’s 5’11” go with a Large.
The fork has a 483 mm axle-to-crown length, which means it’s partially suspension corrected, and the the frame is rated to take up a 140 mm travel suspension fork. With it’s stock fork, the Karate Monkey has a 69° head tube angle, which is pretty steep among “aggressive” hardtails. But that’s with the stock rigid fork. Mounting a suspension fork would raise the front end a bit and also slack out the head angle, probably around 2° if you went all the way up to a 140 mm travel fork.
The Karate Monkey was, hands down, the slowest bike I rode at Interbike. For those of you who are bothered by that, it’s probably safe to say this bike isn’t for you. But for those of you who find that statement to be somewhat self evident, read on.
Two things were immediately apparent on the Karate Monkey. First, I was reminded that Bootleg Canyon is a shitty place to ride Plus bikes. There’s lots of super sharp rocks all over the place, so everyone inflates their tires to relatively high pressures to avoid flats. Particularly on bikes with Plus tires, this means that some of the benefits are lost, and the ride quality isn’t really what it could be. Our intrepid photographer let some air out of the Karate Monkey’s tires to get a little more compliance, and promptly flatted.
Second, it’d been awhile since I’d ridden a rigid bike. No suspension + high tire pressure + me forgetting about both of those factors = sore wrists.
But yeah, the Karate Monkey just kind of feels like goofy fun. The geometry is progressive enough that jumping off of stuff actually kind of works, and even with high pressures, the big tires hook up really well. The tires definitely feel pretty heavy, and that weight is noticeable when trying to push the bike around. But the traction is most definitely there.
There are plenty of hardtails that I get on and it feels like a bike that just wants to go crank out miles. They’re efficient, and even if they’re not that light, a lot of hardtails seem to be built more with an eye toward uphill prowess and crushing miles. But that is most definitely not the Karate Monkey. It feels far more at home riding at a medium pace, looking for little things to jump off of.
If you’re looking for a bikepacking rig or a singlespeed that doesn’t break the bank and can be set up for a wide variety of purposes, the Karate Monkey can certainly do that. But it comes to the table as a simple, straight forward trail bike rather than a marathon XC rig that has some pannier fittings tacked onto it. Personally, I see the Karate Monkey more as a quiver bike. It’s the bike I would take out in crappy conditions to mess around on, or when I’m looking for more of a challenge. Go fast, do skids, pop wheelies. Can I clear that jump on a 33 lb rigid bike? Let’s find out.
The Karate Monkey has a lot of things going for it — it’s relatively cheap, it has geometry that lends itself to radness, it can be set up a bazillion different ways for a bazillion different purposes, and it’s made out of fucking steel. Perhaps most of that was more or less evident just from looking at the product page on Surly’s website, so I guess the purpose of this review is really just to say: Yes, this bike is exactly what you’d expect it to be. It’s probably not going to win any races, but it’s fun, so who gives a shit.