Jaguar E-Type. Ford GT40. Ferrari 250 GTO. Iron Horse Sunday. Legendary machines that ruthlessly imposed their will on the race track to earn their place in the history books of sport, or used their irresistible good looks to steal the hearts of fans around the world. But even legends grow old, and in the world of mountain biking, keeping up with the latest trends is about more than just evolution – it’s about the way we ride. And as impressive as it was under Sam Hill during the glory years, the Iron Horse Sunday would not put up much of a fight against the current generation of DH destroyers. Until today, that is…meet Marvin Mührer and his one-off Iron Horse Sunday Replica!
Tell us a little bit about yourself and your background?
My name is Marvin Mührer, I´m 25 years old and I live in Germany near Hanover. I’m working as a state certified technician in electronics and when I’m not working, I try to be outside most of the time. Luckily me and my girlfriend share a passion for hiking and biking (haha), so we spend a lot of time at local trails or we drive to the Harz which is a low mountain range not far away from our home.
How long have you been riding mountain bikes?
Just one day after my confirmation I took all my money and bought my first real mountain bike, a Bergamont Big Air 6.7. It’s more than 10 years ago now and since then the sport of MTB has become a major part of my life. From early on I was (and still am) a big fan of Sam Hill, his skills and of course his bike. At that time, the Iron Horse Sunday was one of the most innovative downhill bikes.
How did you come up with the idea to create an updated Sunday?
In 2011 I bought my first Iron Horse, the Sunday, followed by the 6 Point 4 and the Transit. You can really call me a fan. The Sunday was always my favorite weapon of choice, from the first ride I was excited about its performance. Then, after a few years of experience in racing not only me but especially my girlfriend and some other friends noted that my beloved Iron Horse is technically outdated and a more up-to-date bike would likely earn some seconds on the race track and also be more fun. And I had to agree, unfortunately! However, after testing some cool bikes, which were fun too, I couldn’t decide and I was still in denial about not riding my Iron Horse anymore. But I happen to know THIS guy…Jens Miller, a friend of mine who is also a genius when it comes to bike design and construction. I really bugged him for a long time until he agreed to start this 27.5″ Iron Horse Sunday replica project with me.
Did you use the existing frame, or build a completely new one?
The idea for a rebuilt Iron Horse already came some time ago, and I knew that just changing the swingarm wouldn’t be enough. It would have had a negative influence on the geometry and therefore on the ride quality. So Jens created a completely new frame with current geometry and improved kinematics, which was also adjusted to my physical proportions and riding preferences.
What were the main challenges? What did the build process look like?
The biggest challenge was to maintain the look, so that people would identify it as an Iron Horse at first sight. We copied every detail except the shape of the top tube, the original one is tapered.
The main frame is a combination of a new tube set and the milled parts from another Sunday frame, which I bought as kind of a donor frame. We could have produced new milled parts, but they did not need to be changed and thus producing new ones was an unnecessary expense.
Additionally, since I don’t like the “normal” style of fork bump stops we made a little change here and created a combined fork bump stop and cable duct, similar to the one from the Scott Gambler for example. To make this part Jens created a casting mold on a 3D printer.
How was the result? Does this bike ride differently compared to the original Sunday?
Unfortunately I did not really have the chance to ride my baby too much for weather-related reasons. But I did do one ride so far and I am incredibly excited. My position in the bike is much better now, but the familiar characteristics of the Sunday have been retained. The rear suspension proverbially irons everything out and the setup works really good. I have to add here, I now use a 350lbs spring instead of a 300lbs in the old frame. I should also mention that it took the short time of only three months from the idea to the finished result. I’m really looking forward to shredding this bike frequently in the near future and I am of course curious to see how my racing results will be affected as well.
How does this bike compare to other modern mountain bikes? (angles, weight, etc)?
All in all, this updated replica frame can be compared to an average modern downhill bike. A few numbers to illustrate my point:
- Head Angle: 63°
- Seat Angle: 76.18°
- BB Height: 341.50 mm
- Chainstay: 455 mm
- Wheelbase: 1272.33 mm
- Reach: 450 mm
- Stack: 613.19 mm
- Weight: 16.3kg
Marvin, congratulations on this very cool project, we wish you many happy days riding your rad new rig in the future. Thanks for taking the time to share it with us too!
Stoked to be able to share! Just one more thing, this is strictly a one-off special and requests for more to be built are not being taken… 😉
photos by Marvin Muhrer, Jens Miller and Jana