Five Signs Your Bike Doesn't Fit
Whether you're riding for fun or riding to win, a bad bike fit can cause discomfort, pain, or even injury. A bad bike fit can derail what should be a fun cycling experience.
Buying a bike can be complicated, and that's where your local shop is supposed to help. The story usually goes something like this:
- Bike shop guy asks the customer what they are looking for.
- Bike shop guy, with a glance, sizes the customer by height. They might even use measuring tape!
- Bike shop guy finds the "perfect" fit that is, magically, in stock.
- Bike shop guy makes a few quick adjustments - seat height and maybe a cockpit adjustment.
- Rider does a few laps in the parking lot.
- Rider decides whether they like the bike. If not, repeat steps 3-5.
And in no time, you're wallet is a $1000 or more dollars lighter and you've got a bike that, hopefully, is a good size for you. The bike guy sounded like he knew what he was doing, right?
Ultimately, if you're going to get the right bike, it has to have a geometry and design compatible with your body, riding style, and goals. And that requires a lot more discernment than what people are getting at the average bike or triathlon store.
Not sure if your bike is the right size? Here are five signs that you bought the wrong bike:
- Spacer Abuse
More often than we can count, riders bring bikes into the shop with a massive amount of headset spacers underneath their stem, or with a stem that is pitched up dramatically. This is a sure sign your bike is too small, the bike isn't configured properly, or both. We see new bikes come out of some shops like this all the time, and there's simply no excuse for a bike professional to sell a bike like this.
Most bike manufacturers recommend just 8 centimeters of exposed steerer tube above the bike's headset, and half of that is then covered by the stem that attaches to the handlebar. You're left with 4 centimeters of steerer tube to work with - any more and something is wrong. These unnecessary spacers make the bike less safe, diminish bike handling, and make the bike less aerodynamic. You can read a more detailed explanation at ttbikefit.com/blog.
Inevitably, someone will say "I'm not able to get that low!" That's okay. The best scenario would have been to buy a bike whose geometry fills that space, instead of you dropping down to it.
- Massive Stem Changes
Bike manufacturers design their bikes to handle and perform a certain way, and changes to the stem, the piece connecting the bike to the handlebars, affect bike handling. If you shorten the stem, the bike becomes twitchy. If you lengthen the stem, it might become sluggish to handle.
Commonly, the stem is shortened to compensate for a a bike that is simply too long for your body geometry. Alternatively, a stem might be lengthened to compensate for a bike that isn't long enough. If the stem is changed more than 2 cm from the stock stem, it's a sign that you might be on the wrong bike.
- Saddle Too Low
Probably 80% of the bikes that come into our shop for a fit have saddles that are too low. If the saddle is too low, performance is diminished, hips are closed at the top of the pedal stroke, and without fail, the rider's knees are pushed away from the top tube to preserve space between your knees and your body.
How does a low saddle result in buying the wrong bike? If you're testing the bike with the saddle too low, then the odds are the rest of the bike isn't configured appropriately either. Raising the saddle will mean raising the cockpit, and that will lead to spacer abuse. It's imperative that you get the saddle height right before you test ride if you want to make sure you get a bike that is the right size.
- Saddle Too High
It's much less common, but we do occasionally see bikes with seats set too high. This almost always results in a rider rocking side-to-side as they pedal and overextending their leg and ankle to reach the pedals. Riders in this situation will almost always report saddle discomfort and will occasionally experience lower back pain.
If your seat is too high and the saddle is lowered, we may need to lower the handlebars as well. If you can't lower the handlebars enough, you may be on a bike that's too big. Once again, if you don't get the saddle height right when test riding, you run the risk of getting the wrong bike.
- Back Pain
The scourge of the cyclist is back pain: lower back pain for the road cyclist and upper back and neck pain for the triathlete. While riding posture can cause discomfort, riding a bike with an incorrect reach can as well. Triathlon bikes are especially susceptible to being too long, as bike manufacturers previously produced bikes with geometries appropriate for time-trial cyclists, not triathletes.
So how can you tell if your bike is too long? For triathlon, you should be able to support yourself structurally, with your elbows almost right underneath your shoulders. Road riders with good posture should be able to reach the brake hoods and shifters without doing a "superman" pose, where both arms are fully extended.
To make sure you buy a bike that fits appropriately, at Tri Shop we use a Fit First approach. With Fit First, you go through our thorough fitting process on a fit bike. The bike is infinitely adjustable, allowing us to put the rider in the perfect riding position before test riding and before buying. The fit bike is then measured, and those measurements are used to go bike shopping.
You can read more about our Fit First approach to bike sales at trishop.com/fit-first.
When you purchase a bike, get one that fits. This article isn't exhaustive, as there's no substitute for the evaluation of an expert bike fitter. That said, these five guidelines should help you understand a few criteria we use to evaluate bike sizing and help you avoid making an expensive mistake. The wrong bike can ruin what should be a fantastic cycling experience. And because cycling is fun, if you aren't having fun, you're doing it wrong.