Chumba Racing VF2 / Lefty Build part 1

Today I begin the project of building my next mountain bike. It is going to be a Chumba VF2 with a Cannondale Lefty fork and a lot of new components from various manufacturers. I am going to go pretty deep with the build, I have found there is usually a lot of interest in this kind of thing.

Oddly, the starting place for my build is the front hub. The hub is made by this great little company called Project 321. They also made a Lefty fork adapter, a Lefty truing adapter and a Lefty hub cap, which we also carry. But this new hub is my favorite piece so far, at least without riding it. Weight, without hub cap and bolt: 115g. Those caps are 11g.

It has a lot of great attention to detail and is worth a close look. Lefy forks use hubs specific to the fork. They are not QR, 20mm or anything like that. The hub axle is integral to the fork leg, and the hub does a light press fit onto the axle. The result is super low flex, in spite of appearances. I feel the Lefty has less flex than any QR fork. It is in a league with 20mm thru axles. The hub a real gem. I hate to mention Chris King at all, but they are the standard here in my opinion. And this hub being made in the USA with this kind of craftsmanship begs the comparison.

What is interesting here is the way the seal is done with an extra snap ring for a better seal. Lefty hubs all seem to wrestle with the issue of getting a little better seal and this is the best approach I have seen.

Cannondale makes a Lefty hub, but so does Mavic, Crank Brothers, Shimano and others. This is how Mavic, Cannondale and some of the others add an extra seal to the Lefty hub. It is a hard plastic cover. They are known to create drag and not seal all that well.

Compare this with my Chris King headset, which will also find a home on my project. Sorry I don't have a hub laying around to compare with, it may be different. But King headsets feature this extra metal snapring around the whole bearing seal. It is an elegant way improve the seal without extra flanges, o-rings or plastic strips. And Project321 chose to go this route on their Lefty hub. So far, so good. I am waiting on much of the build, including the rest of the parts needed for the wheelbuild. I hope to start that next week.