When The Bicycle Paper asked me to write about bicycle stems, I wasn't exactly sure where to start. It seemed like kind of a blasé subject, but what the heck...I'm game. Every bicycle has a stem holding the handle bars to the bike. In youth, a lot of us referred to the stem as the 'goose neck'. Stems come in many varieties, shapes, sizes and colors. Older bikes used different looking stems than modern bikes, but the purpose is still exactly the same...they hold the handlebars to the bike.
Before I started writing, I asked Claire what questions she thought the readers may want to know about stems. She told me that some people want to know if one kind of stem is better, or, what happens to the handling of the bike if you put a different stem on it than the one it came with. Will the steering be negatively effected? Is my bike designed to use a specific length or angle of stem? Once I heard those questions, it did dawn on me that those questions do get asked frequently even here in our shop. So frequently actually, that I forgot that there are those who may still not know the answer.
For this article, let's consider road bikes, since that's the most prevalent form of bicycle that we deal with. Any bike with 'drop style' handle bars falls into the category of road bikes.
1.) Will the steering be negatively affected if I change my stem?
I can answer that question like this: With the proper fit, the proper stem will actually improve your performance. A properly fitted road bike will put the rider's hands on the brake hoods as their most comfortable position. Riding on the top of the bars, or down in the drops should be an auxiliary position for most of us. When you are riding with your hands on the hoods, your hands are spread apart at roughly the same width as your shoulders. On the hoods, your hands are also in the same orientation as they would be if they were hanging to your side. Added to these anatomically comfortable features, the proper fit has the rider's hands right by the brake levers at all times, and for most bikes at least, ready to make an easy gearing change. Your bike and the components on it have been designed toward this type of fit. This is why the brake hoods are soft rubber, and designed for the human hand to sit nicely on them. It's also why manufacturers have moved the shifters right into the brake levers, so that your hand is right there when you want to shift.
The idea of a proper 'sport fit' is to treat the bars like the steering wheel of your car. Everything should be adjusted so that you can reach the steering wheel comfortably. Imagine if you picked your car up from the dealer and the seat was so low or so far back that you had to pull yourself up by the steering wheel shifter or pedals. Driving would be horribly uncomfortable, and your steering would be negatively affected, right?
The same is true on your bike. The stem is an integral part of having your bars in the right place for your arm length, torso length, flexibility, conditioning, etc.... If you have the wrong stem (or the wrong fit in general), the handling of your bike is negatively affected because you may be riding up on the top of the bars a majority of the time. Riding on the top of the bars too much puts your hands in an unnatural 'twist' that causes unnecessary pain. Riding excessively 'up top' also puts your hands very close together and causes neck and upper back fatigue. With your hands that close together, your control is negatively effected. Think of it like driving with both of your hands on the middle of the steering wheel.
A little knowledge can be dangerous:
Now that you know that your stem is related to how comfortable you can be on your bike, there's much more to know before you can diagnose your own problems. Think of your stem as just one consideration of many that make up your proper bicycle fit. Sometimes people change their own stem to try and make themselves more comfortable, but it just makes things worse. There are many aspects of fit to consider before the stem length is adjusted....even if the pain is in your hands, shoulders or neck. Actually, the stem is the last part of a bicycle fit to consider. If you're uncomfortable on your bike, working with a professional bicycle fitter that has the tools and decades of experience is the best way to fix the problem. Ask a friend who they use, and get a fit guarantee. Once you've paid for a professional fit, you should not have to pay over and over again if you're still uncomfortable.
2.) Is my bike designed for a certain angle or length of stem?
If your bike was custom built, then the designer used your fit to create a frame drawing and included a specific stem length to get your proper position. If your bike is not custom built, then whoever fit you for your bike had an idea of the correct length of stem to install when your bike was set up for you. If nobody fit your bike to you, then you would probably benefit by having someone look at your fit, especially if you're uncomfortable or experiencing knee, neck, hand or back pain. Even on a custom bike, it's common to change the stem a little after the rider has ridden it for a while. As your conditioning improves, you'll want your fit to evolve. Fitting is a fluid process, so don't marry the first stem that you get involved with.
If you walk into our shop (R+E Cycles) here in the University District of Seattle, you'll see a wall covered with dozens of stems. We carry stems in many different lengths, angles, colors etc... We perform many bicycle fittings each day, and stems are an integral part of adjusting your bicycle to be comfortable and perform efficiently for your riding style. If you didn't buy your bike at a shop that employs bicycle fitting professionals, chances are that you are riding the stem that came standard on your bike. If we take that one step further, chances are that you are not getting the most out of your cycling experience.
In our shop, every bicycle comes with a fit guarantee. Most people have us change the stem a few times over the course of a few months to get the final fit just right. We do this at no charge, and that's why we have a wall of stems. We can easily swap out a stem to one that gives the rider a slightly different riding position in just a few minutes.
If your bike was not thoroughly fit to you when you bought it, it's like driving your new car without ever adjusting the mirrors, seat or steering wheel when you pick it up from the dealer.
The good news is you can always have your bicycle fit in a shop that specializes in fitting, even if you didn't buy your bike from them. At our shop, we perform fitting services for dozens of riders each month who are uncomfortable on a bike that they got somewhere else. There's a fee involved, and sometimes purchase of some products to get things right, but then any fitting work down the road is covered.
There's one other choice that bicycle owners make regarding stems. This is one relating to aesthetics. There are those out there that want their bike to have a certain look, and it doesn't matter to them if it rides comfortably or not. I'm this way on bikes that I collect and hang on a wall, but for a bike that I ride, I'm not as concerned about the bicycle's 'classic looks'.
There was a time in my life that I wanted my everyday bike to look like a professional racer would be racing it, but that was long before injuries, age, and wisdom;-) If a 'classic look' is important to you too, but injuries and 'wisdom' are quickly making your 'classic fit' not so much fun, may I suggest a collection of classics and an everyday rider?
I can't tell you in an article how high or how low your stem should be, and there's no chart, website, or formula that can tell you your appropriate stem height/length. That can only be done in person during a bicycle fitting session. Nonetheless, I hope that you've learned a thing or two about the purpose and importance of your bicycle stem, and how it relates to fit, comfort, aesthetics, and performance of your bike.
Thanks for reading.
Dan
