The long journey has finally come to a close. The “Experiment In Front End Geometry” series was a lot of fun. I got a lot of positive feedback on this, and I think we all learned a few things along the way.
I have to give credit to OS Bikes for making such a fun machine to do this test with. The bike was a hoot, but I’ll post some final thoughts on it in a separate post. In all, I tested eight different forks on the Blackbuck throughout the duration of this test. The bike never flinched, although I did a couple of times!
When this test began I never thought I would really like anything other than the On One CabonSuperlight fork that I had on it when I started this testing. I can honestly say that there were some forks that I tried that I could have lived with for a long, long time. There were a couple I just didn’t prefer, but in the end I found out something that I thought perhaps would show through before all of this testing began.
It all started after the 2007 Interbike trade show where I rode this bike belonging to Mike Curiak. The geometry was not known to me at the time I rode the bike, but when I found out after the fact what it was, I was astounded. How could a bike with such slack angles and high trail figure handle so well? Maybe numbers weren’t all they were cracked up to be? How could geometry lie though?
Through some e-mails traded back and forth with Mike, I came to a vague understanding that 29 inch wheels were to blame. Yes, the wheel size lets you defy science……well, not really! It would be more accurate to say that the dynamics of the wheel trump the geometry a bit. That is to say, the gyroscopic effect of 29″er wheels allows for things to happen in conjunction with geometry that can not happen with smaller wheel sizes. For one thing, a wider range of fork/front end geometries “works” than with smaller wheeled brethren.
For instance, I was running axle to crown heights anywhere from 430mm to over 500mm and all were rideable on the same frame. I was using these forks with offsets from 38mm to 51mm and all were rideable, which shows that a wide range of fork geometries is acceptable on a 29″er. It may not be your preferance depending upon the specific set up, but the front ends of 29″ers can definitely be tuned to a preferance. The window of opportunity to do that with smaller wheels is much more limited.
So, numbers do not necessarily mean what they did on 26″ers. In fact, you can throw out everything you knew about 26″er geometries, because 29″ers are a whole different ball game. If there is only one thing you take away from any of this, let it be that 29″ers need there own set of parameters. Not only in terms of front end geometry, but in every component made for the big wheeled bikes.
Following are the links to all of the posts relating to this series for quick reference.