This early 80′s steel Moots has some crazy stuff going on…..size specific double seat tube? Whoa.
As I do many times during the week, I fire up my computer early in the morning and take a seat with a good, dark cup of coffee (no cream, no sugar, black only please) and take a spin around the internets to see what is going on in the bike world. Race results, live feed (if something is on), and then a cruise of the more “tech” oriented bike web sites. At this point in my morning routine there is usually something on one of the “tech” sites that almost makes me blow my coffee out through my nose. It’s either some wild claim about “stiffer”, “lighter”, “more vertically compliant” spew that causes my reaction or just reading the comments that are below the article. This can be pretty amusing for sure.
This week I was cruising around one such “tech” site and read the article about a major brand addressing ride quality of their new frame by adjusting the layup of the carbon fiber tubes throughout the frame and changing said layup dependant on frame size, which would address the rider size and weight as you moved up or down from size to size. Revolutionary, right? Not so fast. They have a really cool phrase for their new found technology and have registered a TM for said phrase.
Welcome to the club
In the hand built world of bike frame making we like to call it “size specific tubing” (insert TM). It’s been around for I’d say a couple decades, if not longer. When using “size specific tubing” this means that we change the tubeset (even in our stock sizes) from size to size to get the best ride quality for the given rider that would fit on said size. Bigger frames get bigger diameter tubes and slightly thicker wall and as you move down in sizes the frames get smaller diameter tubes and thinner walls, so across our size spectrum you get a bike that rides incredibly well. This means we don’t use the same tube set for a 58cm as we do for a 50cm and vise versa. If you used that 58cm tubeset for a 50cm build the ride quality of the frame would be way too stiff and make the rider uncomfortable after a short time on the bike. Use the same 50cm tubeset for the 58cm and the bigger rider would feel too much flex. There is a balance between over built and under built. Here at Moots we balance this over 13 or so models that come in an absurd number of sizes varying from 9 sizes per model to 6. That’s a lot of titanium tubing to keep at the ready.
I’m not trying to bash on the guys that are now “size specific” tuning their frames, but welcoming them to the club of great riding bikes.
Now back to cleaning the coffee off my computer monitor.