In 2016, Singletracks began a long-term trail bike analysis, looking at how the geometry of popular trail bikes changed over the years. And change they did, not only in geometry but also in travel and wheel sizes.
As we revisited the numbers every few years, we saw a common theme arising—one you may be familiar with: bikes were getting longer, lower, and slacker.
At the end of 2023, we released the 4th edition of our trail bike geometry analysis and questioned whether we were seeing the end of the long, low, and slack trend. While the data didn’t show an across-the-board plateau, it at least looked as if geometry changes were slowing down. Aside from a few outliers, trail bikes were perhaps finding their sweet spot regarding geometry.
But many bikes, like the new 2024 Canyon Spectral, have only grown longer. Canyon significantly lengthened the geometry of its popular trail bike.
If the Spectral indicates bikes continuing to grow from now to the next production cycle, we may see an increase in another area as well—back pain. At least, that is the belief of Lee McCormack, who connects many of our aches and pains to our bikes’ geometry.
McCormack is a former National Champion downhill racer, author, and mountain bike coach. Over two decades of teaching, McCormack has coached over 11,000 mountain bikers, from first-time riders to professional racers. He has seen what he would say is a significant problem in the bike industry—bikes have outgrown their riders.
And while we may not be able to change the industry, there are things we can do to alleviate some of the aches and pains we may be feeling due to our long bikes. We sat down with McCormack and chatted about his perspective on the problem and possible solutions.
How bike fit and back pain are deeply connected
Back pain, shoulder pain, hips, and knees—McCormack feels that much of this comes from improperly sized bikes. McCormack spoke of the issue from two different angles. First, we are trying to fit our bodies to a mountain bike rather than the mountain bike fitting our body.
“If your foot is a certain length, there’s a shoe that is a good fit for you,” McCormack said. Shopping for shoes, we find a shoe that fits our feet. Rather than being presented with only five options upon entering the shoe store, there is an incredible range of sizes.
Obviously, making shoes in twelve or more sizes is far less expensive than attempting to offer that many sizes for mountain bikes. Most companies provide five sizes, give or take, and a size chart with recommendations.
McCormack argues that the reach–which we’ve seen grow and grow is now likely too long for us and we’re forced to over-extend.
Why are we “stretching” to fit a bike and not just sizing down? McCormack feels that has much to do with industry marketing and the current “long, low, and slack” trend., and long bikes sell.
“Right now, long, slack, and low are the metrics—how stable it is,” McCormack said. “Back in the 90s, it was about agility—how agile the bike is.”
He isn’t wrong; mountain bikes have grown over the years, with the industry touting that a long bike is a stable bike. A Specialized Stumpjumper’s reach has grown by more than 40mm since 2016. What likely didn’t grow in those eight years, however, is the length of our arms, and thus McCormack says, we’re stretching more to reach the handlebars during descents.
Yes, seat tubes have become steeper, and bring us closer while pedaling, but descending is a different story. Stretching to reach the handlebars can cause many different issues.
“It’s the whole chain,” McCormack told us. “You’re looking at your hands, wrists, elbows, shoulders, back. You can get hip dysfunction, too, because if the bike’s really long, in order to reach, you have to hinge on the seat.”
A longer bike may be more stable, but McCormack feels they are a cause of chronic aches and pains.
What is span or Rider Area Distance?
If you are in the market for a new bike, getting one that fits you well will significantly help reduce aches and pains. But, rather than going with the traditional sizing model or even determining the size based on reach, McCormack recommends reviewing another measurement.
While reach is still important, McCormack argues that the Rider Area Distance, or RAD, is the most significant measurement on a bike. RAD is essentially a measurement from your bottom bracket to your grips. It incorporates reach, stack, bar rise, sweep, and spacers under your stem.
According to McCormack, when a bike fits your RAD size, “You have optimal arm range for bike handling: descending, braking, cornering, pumping, dropping, and all the fun stuff. You can generate maximum torque for power moves: sprinting, steep climbing, pumping, manualing, hopping, and wheelie drops.”
UK mountain bike brand Privateer recently released the second generations of the 141 and 161 full-suspension mountain bikes and included a span measurement. The idea works similarly to RAD, with a line from the center of the bottom bracket to the top of the head tube. It’s one of the first brands Singletracks has seen incorporate the measurement into a geometry chart.
To find your RAD size, take your height in CM and multiply it by 4.47 if you are a male and 4.6 if you are a female. McCormack said some of his clients take a length of string with a knot tied at their optimal RAD measurement to bike shops to shop for a new bike.
Your RAD measurement might place you on a smaller frame than anticipated.
Exercise
If you’re not in the market or can’t afford a new bike, you can make do with what you have. And getting stronger will help.
A longer reach will cause you to hunch over more, stretching for the handlebars causing back, shoulder, and other pains. Intentional strengthening exercises can help prevent and alleviate some of this pain.
“You can get really strong. That will allow you to ride harder and longer, but there’s a limit,” McCormack said. Focusing on strengthening your core, back, and shoulders can help offset the issues that arise from a longer reach.
Bike fitting with the proper components
If your bike is too long, changing your stem for a shorter one is a great option and will bring the handlebars back toward you.
McCormack also recommends trying a handlebar with more backsweep “Most of the time, I put [my clients] on a handlebar with increased back sweep,” he told us. “I’m a fan of SQlab. There are other ones who make the 16-degree bar.”
These handlebars bring your hands closer to your body and can help prevent wrist pain and issues. “The natural grip angle of your hands is not eight or nine degrees,” McCormack said. A bar with an increased backsweep puts your hands, wrists, elbows, and shoulders in a completely different position.
Another simple change you can make is moving your seat position forward. This will effectively put your seat and handlebars closer. However, McCormack mentioned this only helps with pedaling and climbing, not descending.
In a 2018 Singletracks article on fixing five types of pain while mountain biking, professional bike fitter Jason Williams of University Bicycles in Boulder also suggested that too narrow of a saddle could lead to the rider rolling their pelvis back too much to relieve pressure, also increasing the length of the cockpit. A wider saddle may help the rider neutralize hips and mitigate back pain.
Williams also said back pain is often a result of overextension, and riders should double-check their saddle height. A saddle that is even a little too high also causes back pain.
Lastly, stretching tight hamstrings which are connected to the pelvis and can pull on your hips may help too, said Williams.
You can always try a smaller, or older, frame
Depending on how short you are, you may struggle to find any bike that fits. “If you’re 6’4”, you can finally find a bike that fits you!” McCormack told us.
For those riders falling below “average” height, McCormack says it may get more difficult as time goes on to find a frame that isn’t too big–though every brand produces sizes differently, and the bigger the bike company, typically the larger their size range is.
Working with a custom frame builder to design a bike of the perfect fit is always an option too. However, this may be out of reach financially for some people. So, McCormack offered some different options.
“Find an older bike,” he said. Older bikes tend to have shorter reaches, and you will be more likely to find a RAD measurement that works for you. McCormack stresses the RAD measurement’s importance over industry trends such as wheel size. “26-inch wheels didn’t stop rolling all of a sudden.”
It is also worth reviewing bikes from many different brands as some are more conservative with their geometry and others more aggressive and lengthy.
Above anything else, McCormack thinks mountain biking should be fun. Despite what some may say, he feels that suffering shouldn’t need to be a part of the sport. Aches and pain shouldn’t be prevalent when we choose mountain bikes that better fit our bodies and start caring better for our bodies.
