Over the next month, retailers all over the United States will be advertising their Black Friday discounts and will be doing their best to entice people to spend money. Retailers in the endurance sports space are not exempt from this, so it’s very likely that you’ll be seeing very enticing deals from bike shops or bike manufacturers about bicycles.
New Bike Day is one of the most exciting days possible for a cyclist or a triathlete, and thus the prospect of buying a new bike can be very exciting. There are important considerations to take into account when thinking about purchasing a new bike to ensure that New Bike Day really is a wonderful day.
A lot of athletes consider a Bike Fit once they own a bike, but truly, a proper Bike Fit starts before a bike purchase. New Bike Day can very quickly turn into Very Sad Day if the bike isn’t a geometry that works for the athlete.
One of the tenants of Bike Fit is that we seek to make the bicycle look like the rider; we do not want the rider to try to contort themselves to look like their bicycle. This starts with the geometry of the bike itself. In my experience, the most important geometry measurements to get right when purchasing a bike are the reach and stack.
Reach is the horizontal distance from the center of the bottom bracket to the center point of the head tube. Stack is the vertical distance from the center of the bottom bracket to the center point of the head tube. Stack and reach are very important because they can help you determine if a given bike is going to offer you the riding position you are seeking.
It’s very important to understand that not all bike (frame) sizes are created equal. One bike model that is a size 56 is not the same bike as another model that is a size 56, even if they are made by the same manufacturer. Bike sizes (or frame sizes) used to refer to the length of the bicycle’s seat tube, but this is no longer the case in many instances. Stack and reach offer more insight into how the actual geometry/size of the bike will work for a rider.
Stack and reach cannot be changed. This means that if the stack and reach are inappropriate for a given rider, the bike will never fit the rider properly. This can lead to a suboptimal riding experience, with the worst-case scenario being that the rider gets injured or is in pain from riding the bicycle. An experienced bike fitter can get the bike as close as possible to looking like the rider, but if the stack and reach are not right, there will be a point where they cannot adjust anything further.
All too often, I hear of athletes making bike purchases because “it was a good deal” that they “just couldn’t pass up.” Unpopular opinion warning: It isn’t a good deal if the bike isn’t actually the right geometry for you. You know the phrase “close only counts in horseshoes”? Well, we can apply that to bike purchases and bike fitting as well. In almost all cases, close is simply not good enough, and as much as you may not want it to be true, you’re probably not the rare exception to this.
Components refer to all of the “extras” besides the bicycle’s frame that are necessary for the bicycle to be used and include things like wheels, tires, groupsets (which includes the cassette, chain, derailleurs, and cranks), brakes and shifters, pedals, and finishing parts (which include the stem, handlebars, seat post, and saddle).
Groupset components get a lot of attention, but there are other components that I think should get the most attention, most notably the stem, handlebars, and saddle. Contrary to what most people value most about groupsets (such as electronic or cable shifting), the crank arm length is what I think is most important to discuss when talking about groupsets.
Going along with the ideas shared about Bike Fit above: There may be items on a bicycle that need to be swapped out in order to make the bike suitable for a given athlete. This is very frustrating to many athletes, especially when the price of a bike can be quite high. The items listed above (crank arms, stem, handlebars, and saddle) are the items that most commonly need to be swapped out in order to optimize an athlete’s riding experience.
Here’s the truth: Bicycle manufacturers ship bicycles with components that are “standardized” based on a bunch of metrics that may or may not actually apply to you. It is cheaper for bicycle manufacturers to ship a bike with standard-sized components, and just because those components come with the bike does not mean that they are the right ones for you. In order to offer customization from the time you order a bicycle, the price of the bicycle would rise to a point that would be off-putting to most consumers. So, they sell the bike with standard-sized components and tell their target audience that this will likely work for them. It might…and it might not.
Crank Arm Length
The standard length of crank arms that currently ships on bicycles is generally 170mm, 172.5mm, or 175mm. Based on what I’ve seen in coaching and bike fitting, these lengths are much longer than are necessary or comfortable for most riders. The bicycle industry is very slow to adapt and change, so even though this has been known among bike fitters for years, the industry hasn’t changed the length of crank arms that comes with the purchase of a new bicycle.
One of my favorite ways to illustrate this idea is this: If you were asked to jump onto a box 100 times, would you want to jump onto a 12-inch box 100 times or a 6-inch box 100 times? Of course you’d want to jump onto the shorter box and save your body the strain of the extra length. The same is true of crank arm length, which is how you are “jumping” (rotating) around the bottom bracket of the bicycle.
There are many benefits to getting shorter crank arms than the industry standard. Here are just a few:
Increased saddle comfort due to reduced saddle pressure due to shortened length to reach to the bottom of the pedal stroke.
Reduced strain on the knee joint (which can lead to reduced knee pain) due to reduced knee flexion at the top of the pedal stroke.
Higher average cadence without having to do additional work to train the neuromuscular system.
Any biomechanical asymmetries you have will be amplified by longer crank arms; going to shorter crank arms evens them out.
While crank arms that are too long for you can be problematic, I don’t see as many issues when riders are riding crank arms that are shorter than average. Most issues do stem from too much length.
The stem of the bicycle controls the placement of the handlebars relative to the front wheel hub and impacts contact point reach (which is different from frame reach, which we discussed above). Contact point reach refers to the distance from the front tip of the saddle to the top of the hoods on the handlebars.
A stem may need to be changed out if the rider’s contact point reach is too long or too short. It’s important to note that significant changes in stem length can alter the handling of the bicycle. If a stem is too short, the handling of the bicycle will be too twitchy. If the stem is too long, the handling of the bicycle will be too labored or clunky.
A lot of athletes make the mistake of thinking that they can compensate for a bicycle that has an incorrect frame reach by modifying the contact point reach. Yes, the effective reach can be changed to a point, but again, since frame reach cannotbe changed, a bike that is the wrong geometry/size can only be altered so much and will never work optimally for a rider.
Like crank arms, bicycles of a given frame size are shipped with a predetermined “standard” of handlebar width, which may or may not work for a rider. Proper handlebar width is a personalized thing and should be based on a specific measurement of the distance between a rider’s acromia (the pointy bits of bones that one can feel where the arm meets the shoulder).
In my experience as a bike fitter, I have seen bikes that had the proper stack and reach for a rider ship with handlebars that were a full four centimeters too wide. Even one centimeter too wide will be felt by the rider and can cause pain or numbness throughout a ride.
The saddle is the part of the bicycle that most riders are familiar with swapping out, as it is understood by experienced athletes that there is no “one size fits all” when it comes to saddles. This being said, the road to finding the right saddle can be seen as frustrating, seemling endless, and expensive. Without previous riding experience or a bike fit, it is impossible to determine which saddle will work for a given rider, so bicycle manufacturers just ship bicycles with stock basic saddles.
Similar to how running shoes should be selected based on an athlete’s foot size and three-dimensional foot shape, a bicycle saddle should be selected based on a rider’s specific physiology and anatomy and the type of riding that they are doing.
A road riding position is vastly different from a time trial (or triathlon) position, and as such, the same saddle rarely works for both positions. It’s important to determine what the primary fit position will be: road, time trial, mountain, gravel, or commuting. Once a rider determines the type of riding they will be doing, they can select a saddle designed for that type of riding that meets their physiological and anatomical needs.
Saddle width is one of the most important considerations beyond saddle type. For road or upright positions, the distance between a rider’s ischial tuberosities (sit bones) is used to determine saddle width. For time trial positions, it’s more important to select a saddle that is the appropriate width between the pubic rami bones. While a rider’s sit bone width can be measured by a bike fitter, there is no ethical or appropriate way to measure the width between a rider’s pubic rami bones in a bike fitting setting, so trial and error with saddle tests is needed to determine this.
Beyond saddle width, saddle length and saddle shape are important considerations. Trial and error is generally needed to determine what length and shape will work best. Good bike fitters will have demo or test saddles that you can try during a Bike Fit.
New Bike Day is a very exciting day, and considering purchasing a new bike is a very exciting thing. However, an athlete should consider more than just the color, look, and shifting components of the bike when making a bicycle purchase. Additionally, they should understand (and expect) that they will need to invest some additional money into the bicycle once it arrives to make it the most comfortable it can be for them. Remember: Speed comes from comfort. You will only be your strongest and fastest on a bicycle if you are riding the bike with the right components for you.
Coach Laura Henry
Laura Henry is a Syracuse, NY-based coach who is a USA Triathlon Level II Long Course and Level II Paratriathlon Certified Coach, USA Cycling Level 2 Certified Coach, VFS Certified Bike Fitter, and has successfully completed NASM's Certified Personal Trainer course. Coach Laura is passionate about helping athletes of all ability levels reach their goals and has coached many athletes to success.