The name Stumpjumper is one of the most well-known in mountain biking. Specialized introduced the first major production mountain bike when it launched the Stumpjumper all the way back in 1981. Since then, the Stumpjumper has become so iconic one has even been displayed at the Smithsonian. Now, in its 9 iteration, the Stumpjumper has seen a significant redesign that keeps it at the leading edge of the sport.
The Stumpjumper now comes in three different versions; the Stumpjumper, the Stumpjumper ST (short travel), and the Stumpjumper EVO, with all models available in 27.5 and 29er versions. The ST is snappy and nimble, the Stumpjumper rides fast and planted, and the EVO is for anyone that eats and sleeps gravity riding with its slacked-out geometry.
From a visual standpoint, the most striking design element that riders will notice is the all-new sidearm design. Specialized pulled out all the stops to lighten and stiffen the Stumpjumper frame, and the sidearm design is a vastly more efficient structure.
Finely Tuned: Specialized fine-tuned the Stumpjumper’s front-end stiffness. The bike handles like it’s on rails. Point it where you want, and you’re going there.
More Precise: The sidearm design directly connects all three mounting points of the rear end and shock to the frame, which creates a significant increase in frame stiffness and suspension performance.
Stiffer and Lighter: Specialized set out to create the best-handling trail bike possible. They also wound up creating one of the lightest trail bikes anywhere.
The new Stumpjumper offers the ultimate in adjustability. Both the 27.5 and 29er frames can fit up to 27.5×3.0″ tires. Specialized has also added a flip chip to the rear shock to allow for adjustability and tunability by the rider. All Stumpjumpers come with the flip chip in the low position and can be flipped to raise the bottom bracket height by 6mm for an increased bottom bracket and pedal clearance. This will also change the headtube angle by .5°. All the models use standard stroke and eye-to-eye metric shocks, making it easy to swap out shocks if you want something a little different. The bikes also use threaded bottom brackets making it easy to find parts.
Initial Impressions
Our bike gurus Joe and Rob had the opportunity to travel to California earlier this year and ride the new Stumpjumpers on some amazing trails. Here are some of their impressions:
What changes are you excited about?
Joe: The new Stumpjumper truly is the ultimate trail bike. There are many exciting changes. However, I have a few favorites. First, the new linkage with the sidearm frame design is a crucial component of how well this new Stumpjumper rides. Second, the installation of the flip chip in all frames along with the tire clearance allows for a wide range of adjustability. Lastly, the redesign of the downtube on the new Stumpy frame gives you 20% more volume in the SWAT Down Tube Storage.
Rob: I’m excited about a number of things. Joe already hit on a lot of the technical aspects, so I’ll touch on something else. The bike is striking. The lines, the angles, and the shapes are beautiful. Before I noticed anything else, I looked at the bike and said, “Wow, that bike is hot.” I’m also super excited about the adjustability of the new Stumpjumper. Having the option to run multiple wheel and tire sizes with very little needed adjustment to the bike itself is super nice.
How did the bike ride?
Joe:
With all of the new updates and innovations to the Stumpjumper, I was pleasantly surprised at how well it climbed. The new sidearm frame along with the FSR suspension redesign helps the new iteration of Stumpjumper climb almost as well as an Epic but still descends like the fun trail bike the Stumpy is meant to be.
Rob:
The bike rode amazingly. As someone who can appreciate a nice bike but has trouble feeling the minute differences, I was able to feel how much stiffer this version of Stumpjumper is. When we were in California testing the bike the rides started with a 3 ½ mile climb. Basically, from the ocean to the mountain. It was HARD for a Clydesdale! But, I immediately noticed how much stiffer the frame and suspension were. Noticeably more of my pedaling forces were going through the bike and not being lost to frame flex and suspension movement. Then, when it was time to come down, that stiffness and suspension efficiency had me stuck to the trail. It had been almost four months since I had ridden a bike in mountain conditions and I was confident and fast coming back down those 3 ½ miles!
FAQ
What are the main differences between the Stumpjumper, Stumpjumper ST, and Stumpjumper EVO?
The main difference between the three is the suspension and geometry. Each is optimally designed for all types of trail rider preferences and comes with ultimate adjustability. As you move from the ST, to the SJ, to the EVO, suspension travel increases and the geometry gets more slack.
What is the purpose of the new sidearm?
The sidearm is a piece of the overall stiffer and lighter chassis. It has a direct connection at the front and back of the rear suspension to optimize stiffer frame characteristics. The frame, therefore, has less deflection and provides a more stable and balanced ride.
What is RX tune?
Every bike is different, and therefore every shock and fork needs to be tuned for that bike. Specialized has an in-house team that works on tuning shocks and forks to make them ride appropriately for every model and wheel size of the Stumpjumper. Women’s specific bikes come with women’s specific RX tunes that are based on female rider characteristics, but any men’s bike can be sent in for a women’s specific tune. Female riders are typically lighter, so Specialized adjusts the volume, compression, and rebound accordingly for every frame and wheel size. The goal is for the shock and fork to perform the same at lower pressures for lighter riders.
What’s so unique about the new chain-stay protector?
It’s not often that a chain-stay protector receives a lot of attention from engineers and riders. The Stumpjumper’s new chain-stay protector is designed to reduce the amount of chain slap significantly and is the quietest chain-stay protector to date. What makes it so effective is the wave design in the rubber that reduces the harshness of the chain slap by decreasing the frequency of the chain slap. If Specialized put this much thought into the chain-stay protector, you know they put a lot of thought into the overall bike.
Once again, Specialized is leading the way with the all-new Stumpjumper. This bike is now available at select ERIK’S locations, so swing in or check out shoperiks.com to learn more.