2009 GT Marathon Carbon
My 2009 mountain bike race machine was a GT Marathon Carbon Pro. I have spent the last 9 months putting this bike through the ringer of the Colorado mountain bike racing circuit. The bike has performed flawlessly for me in all the races I have entered and has never let me down on the long training rides.
The Frame:
GT’s Marathon Carbon lineup of bikes all employ the same full carbon main frame with a carbon/aluminum rear triangle. This main frame is built with large tubes of carbon weaving which all make for a work of art or as some of my friends say, a bike from the future. The bike has smooth lines like a European sports car and turns heads wherever I ride it.
The brains of the Indepedent Drivetrain suspension system
The frame provides 100mm of rear wheel travel from GT’s patented Independent Drivetrain suspension system. This is GT’s latest rendition of their 1999 version of the original I-Drive. What makes this system superior to other designs is that the system has very little pedal feedback both sitting and standing. The design also does not require a specially valved rear shock to prevent pedal feedback. While my model did come with a Fox RP23 shock with the pro-pedal technology I found I enjoyed the suspension more with the shock fully open.
The Parts Pick:
The Pro model of the Marathon comes with a complete Shimano XT drivetrain and is paired with a Fox RL120RC fork and RP23 rear shock. The wheelwork was supplied by Mavic Crosstrails matched with Kenda Karma tires. This is quite a parts package by GT Bicycles and in today’s bike market it is getting harder and harder to find bikes with full Shimano parts groups and name brand wheels. The MSRP for the bike is $4,399 however most shops are selling them for around $3,200 which is a near bargain for a bike of this caliber.
As always the Shimano drivetrain provided flawless shifting and the new shadow rear derailleur is a striking design which tucks the derailleur under the chainstay and away from trail obstacles. I’m hoping that SRAM follows suit to build derailleurs that are a bit more stealth. The bike I had briefly before the GT was a Scott Spark 35 which was equipped with SRAM derailleurs and on the second ride I tore the rear derailleur off barely grazing a rock.
A full Shimano XT parts kit standard
The Shimano XT servo wave disc brakes provided plenty of stopping power for the type of riding I do. I have heard from a lot of riders that they do not think the stopping power is adequate and have upgraded to Hope’s or the Avid Elixirs. I rode the entire season using the Shimano stoppers and couldn’t have been happier with their performance.
The only change I made to the bike for the race season was the addition of a Thomson seatpost, shorter stem, and a set of Stan Tubeless wheels with Maxxis Crossmark tires. The Thomson stem allowed me to get a bit further forward on the bike than the stock Ritchey Pro setback post. As I wanted to lessen my reach to the handlebars I also swapped out the Ritchey Pro stem to a shorter 90mm Race Face stem. These two changes allowed me to still have an aggressive stance on the bike, but provided a greater level of comfort for the long distance races with a slightly more upright ride.
Stan’s Tubeless wheels were the big addition I made to the bike. I decided on the Stan’s system for their track record of great products and the price was right for an extremely light weight racing wheel. Just like most bike geeks in the racing world, I only rode the Stans wheels on race day and my more durable Mavic Crosstrails during training.
The Ride:
One can go on and on about how awesome the parts are on a bike, but when it all boils down to it, if the bike is not a good design, all the great parts are simply after thoughts. My first ride on the Marathon was at my local open space area called Green Mountain in Lakewood, Colorado. Winter in Colorado usually does not end the mountain bike season, so I was able to ride my new bike only a few days after receiving it.
After adjusting the air pressure and fork/shock pressure a few times on that first ride I was able to see what the bike was capable of. I took it on a 20 minute lung busting climb to see how the suspension would react under constant pedal pressure. The suspension rolled over everything with ease and I found myself able to sit in the saddle through terrain where other suspension bikes would force me off the saddle. I did notice some suspension bob under hard pedal strokes, but to be honest I did not feel like I lost any power from the suspension. I felt as efficient on the Marathon as I have on hardtails for long climbs and best of all I didn’t have to be choosy on my lines. I actually prefer the suspension fully open on the climbs to let it work for me. Never did I feel like the suspension worked against my efforts which was a welcome sign compared to my previous full suspension bikes.
What goes up Must go Down!
Marthon Pro: check!
One of the biggest advantages to a full suspension bike is the ability to descend with more confidence and to be able to ride through sections that most hardtail riders would avoid or ride around. The first downhill action my Marathon saw was a section of Green Mountain called Box of Rox (and it would see this section countless times throughout the season). This trail is named that for a reason and for the nearly 1.5 mile descent there is nothing but rocks strewing the trail many of which can cause pinch flats or even tear sidewalls.
I took the first section a little slow to see how the suspension would react when I applied the brakes. My previous Scott Spark’s rear suspension almost locked up entirely under rear wheel braking. I was shocked to see that the GT ID suspension system remained fully active even under heavy braking.
The braking of the Shimano XT calipers slowed me down plenty going into the many switchbacks on the descent and the Kenda Karma’s had enough grip for the corners, though a more knobby tire probably would have provided even more traction.
The Long Range Test:
The 2009 season brought me all around Colorado for many different races and rides with just about every kind of terrain. As most know, Colorado is known for having incredible climbs in just about every mountain bike race and of course screaming descents. My GT Marathon Carbon Pro was pushed to its limits during these long climbs and descents and the stability and control was spot on.
Since most of the races I competed in during 2009 were the “Marathon” variety it seemed fitting that the bike I rode was called Marathon. GT did their testing and research to build the perfect long distance mountain bike racing machine. What is great about the Marathon is that while it proves to be a great race bike, it is also a great trail bike. Trail bike seems to be the newest term for the type of riding between cross country and free ride. The suspension on the Marathon provided 100mm of rear wheel travel, but it felt almost endless to me. I took the bike for a day of lift access riding at Winter Park resort. The 120mm travel Fox front fork gobbled up everything I threw at it and the Shimano servo wave disc brakes worked great even after 10 screaming runs down through Winter Park’s mountain bike terrain park.
The biggest test I threw at the Marathon for 2009 was the Leadville 100. This race has become the ultimate endurance mountain bike event in the country and for good reason. The terrain is ruthless in Leadville with nearly 15,000 feet of climbing and descending. Equipment matters for events of this magnitude and the Marathon worked flawless for the 100 miles I endured. I never had any mechanical problems, only bio-mechanical problems, but that’s another story.
The 2009 Marathon Carbon Pro is a great race bike and great trail bike. This bike can take almost anything you can throw at it. Carbon fiber is an amazing material for mountain bikes and the Independent Drivetrain technology provides smooth efficient pedaling and great bump absorption. You can’t go wrong with GT’s latest offering of Marathon Carbons and I expect this bike to be a top endurance racing and trail bike pick for years to come.
Unite the mountain bike movement by strengthening our grassroots network of affiliated clubs and their members.
Provide truly world-class riding experiences and model trail systems nationwide, particularly “Gateway” trails in towns and cities.
Protect natural lands and open space by bolstering volunteerism and sustainable trail design.
Expand on 2009’s successes with programs like Take A Kid Mountain Biking Day and Team IMBA to get more riders on bikes at every level.
