Words by: Max Morgan
In this MTB stem guide, we are going to breakdown everything you should consider before buying a new stem for your mountain bike. The stem's sole purpose is to clamp the handlebars to the steerer tube. Most stems are available in different length and rise options and are manufactured with different materials using different processes. In a nutshell, there are plenty of options available for aftermarket stems and can be used to dial in the fit and ride characteristics of your bike.
The first thing to consider when buying a new stem is the length. Not only does the stem length affect the fit of the bike, but it plays a big role in how the bike handles. Using a shorter stem gives the bike quicker handling characteristics and a more responsive feel. A longer stem shifts your body weight towards the front of the bike and puts you in a better pedaling position, especially on those steep climbs.
With the trend nowadays leaning towards longer and slacker bikes, for a lot of people using a traditionally shorter stem makes sense. For those aggressive trail bikes out there, we recommend using a stem in the 50-60mm length range. Of course, this may not work for everyone. In some cases, sizing up a frame size and using a 35mm length stem may give you a more comfortable fit. It is important to consider both the fit and function of different length stems.
Size XL Yeti SB45c With A 32mm Length Race Face Turbine Stem
The stem rise refers to where the handlebars are placed relative to the stem, measured as an angle in degrees. Think of drawing an imaginary line from the bottom of the stem to the bottom of the handlebars. Some common stem rises are 0° and 6°. With a 0° rise, the stem does not raise the handlebars at all. With a 6° rise, the handlebars will be raised higher relative to the stem. With most stems, they can be flipped over to also get the same amount of drop. Keep in mind that using stem spacers can be used to change handlebar height as well.
This is sort of a loose MTB stem guide because getting the correct fit and function you are looking for is most important when choosing the correct stem. A general rule of thumb is that the more aggressive the bike gets, the shorter the stem can be.
Race Face Atlas Stem Mounted With Renthal Fatbar Lite Carbon Handlebars
Over the last couple of years, we have seen the industry pushing more 35mm clamp diameter handlebars and stems. The two different standards certainly have tradeoffs. 35mm clamp diameter handlebars and stems can potentially increase overall stiffness and durability. Keep in mind that more stiffness isn't always the right answer! Having a handlebar and stem combination that is also compliant to the vibration of the trail is important. The 35mm handlebars, when done correctly, can actually be lighter than its 31.8mm counterpart while maintaining the same strength. On the contrary, it is possible that the two handlebars could be the same weight, one being stiffer than the other. In the end there are a lot of variables that come in to new mountain bike "standards" and everyone has there own preference as to what works and what doesn't.
Renthal Apex 35 Stem Mounted With Renthal Fatbar Lite Carbon 35 Handlebars
The TruVativ Hussefelt stem might be one of the most iconic stems out there when it comes to modern mountain bikes. I think I had this on my dirt jumper 10 years ago and it hasn't changed much, and that is a good thing. It has proved to be able to take a beating and is still one of our best selling stems, especially in 31.8mm bar clamp variety. There aren't many stems coming in that length and I actually prefer to run 31.8mm handlebars, which makes this stem a great option. It's a bit heavy, but for the price, you get an amazing stem. It comes in a few lengths, but our most commonly sold model is the 40mm length x 31.8mm clamp.
Next up is the RaceFace Chester stem, which despite being a slightly newer option, has been selling like crazy. This is due to two things: the price is almost unbeatable for a high quality 35mm clamp stem, and it looks good as well. It's equally at home as an upgrade on a slightly older bike or to throw on your brand new high end dream build. The Chester takes its design from its bigger brother the Turbine R, and comes in a more affordable package using forged alloy instead of being machined. This stem also comes in a few different lengths, or as you could say, different strokes for different folks, but our most popular selling stem is the 40mm length x 35mm bar clamp.
Mentioned above, the Raceface Turbine R stem finds itself at home on most of the bikes belonging to our beloved founder Jeff. While he prefers a different length than our most popular seller, there are a few reasons he loves this stem more than others. First is the square, CNC machined block of the stem. It takes top honors in the looks game, while also coming in second out of five on our list for the lightest stem. Yes, Jeff has been known to be a weight weenie, especially on his trail bikes. The best selling version of the Turbine R stem is the 50mm length x 35mm bar clamp, however, Jeff likes to ride the 32mm length x 35mm length on most of his bikes.
The OneUp stem works great with their handlebar, looks good, and can be used with or without the EDC preload. While almost all stems do the same job, the OneUp stem is the outlier, with its own way to preload your headset bearings, OneUp has innovated once again. As many are familiar with OneUp’s EDC tool system going into the steerer tube of your fork, it used to require threading your steerer tube for this to work, which is a bit of a pain. The EDC stem has the ability to use a preload wedge on the inside of the stem during installation. You tighten your stem, then hit the preload screw until the headset does not have any play. In addition to the super innovative preload system, the stem itself is also very good. Looks are great with a good square block to the stem, it’s right at home on any trail or enduro bike. It's made from durable forged 6061-t6 aluminum. While it's not quite the lightest, it's also not the heaviest, and will allow you to use your EDC tool without threading your steerer tube! Note that the preload kit is sold separately from the stem, and the stem can be used as a traditional stem as well.
I think the Renthal Apex stem might be one of the most popular stems on the market in general. It also happens to be one of the lightest in the trail/enduro category as well. Those might not be related, but I wouldn't add weight to my bike on purpose. The Renthal Apex stem features some amazing CNC machining from a solid 7075 block of aluminum and a two piece faceplate design as well. The two faceplates are also anodized gold-ish and look amazing when paired with their alloy or carbon handlebar. This stem also happens to be the only stem with a positive or negative rise to it, which is becoming less common to see in this style of stem. Some people will enjoy this feature, some will be indifferent, and the rest won't know the difference, and that is ok. The best selling version of this stem is the 40mm length x 35mm clamp.
At the end of the day, we all need a stem to ride our bikes. While you might be looking to upgrade your stock stem, trying to make your bike look just a bit better, or you haven't thought about it at all, we hope this will guide you to make the best decision for you. From the good looking affordable Chester, to the light and amazing looking Renthal Apex, and the innovative OneUp EDC stem, you have all the options here to choose from.
This article was written / authored by Max Morgan. Max has been a professional downhill mountain bike racer for the last 10 years, competing in the UCI World Cup downhill series and U.S. Pro GRT series. Having ridden all different kinds of bikes on trails all over the world, Max's experiences being out on the circuit give him a unique perspective on what makes for a quality cycling component. Max also has degrees in Mechanical Engineering and Physics, and so if you don't see out on the trail, chances are he is probably in the garage tinkering on the next project.