You need a couple of special tools, and the assembly is complicated. (This is opinion based, but quite a lot of it online, there are no measurements.)Ī Lefty is much harder to service than a normal fork. So now the newer ones should have more progressive compression. Previous models, as some bikers on forums complained, had more linear action: they were easier to bottom than normal forks. Post-2013 models have a rubber-sealed leg with bearings further inside and with one plain bearing at the bottom which allows for service intervals as normal forks:

So that means that my just over a year old road bike is for sale. This required almost constant maintenance. The Bad/Mad Boy features a rigid version of Cannondales Lefty fork, and a nice stem. Pre-2013 models of Lefty are not sealed, having the bearings track just under a rubber sleeve. The front of bike will look unbalanced until you get used to it. The axle works only with Cannondale hubs. If you need to remove the front wheel, you need to remove the brake caliper also. You can replace the tire without removing the wheel. The heaviest Lefty is still lighter than lightest carbon 2-legged. Having bearing-fitted 2-legged fork is an overkill and unnecessary weight. Having conventional fork with one leg wouldn't work, such a fork would get stuck. Such solution works with almost same friction under heavy side-loads, whereas sliding tubes, when side-loaded (uneven compression of legs), do get friction losses (rolling resistance wins). While normal forks have round tubes that slide on oil film, the Lefty uses needle bearings on a square profile (same as the front leg of Boeing airliners.): This design is used also on cars where the wheel doesn't have support from the other side. The wheel axle is one-piece with the bottom part, which is stiffer than a quick-release axle (which is not solid at all) and on same level as a 15 thru-axle or 20 thru-axle. The top is attached like a dual crown downhill fork, which is much stiffer than a single-crown. But because of its different construction, the fork is actually stiffer than most 2-legged. The single-legged fork must truly withstand heavier bending forces than conventional forks, simply due to physics and asymmetricity.

Cannondale lefty fork for sale