Cannondale Introduces the New F-Si and Lefty Ocho

Cannondale is known for its unique approach to engineering and design. From mountain bikes to motorcycles, Cannondale has never been afraid to try new things. Sometimes they’ve worked out and sometimes they haven’t. Back in 2015 Cannondale launched the F-Si hardtail that introduced the world to its Ai offset and, for the time, progressive geometry. We tested the F-Si and were impressed with just how rowdy a hardtail could be. Fast-forward to today and Cannondale has revamped the F-Si and introduced the eighth version of its Lefty suspension. 


When the F-Si was originally introduced back in 2015, it was one of the first cross-country race bikes to come out with a less-than-traditional design. With slacker angles and shorter chainstays, the F-Si proved that XC bikes could be more capable with the right geometry. For 2019, the F-Si has an updated geometry that blends modern trends with an eye towards the future. 

Cannondale went even slacker with this generation of the F-Si with a 69-degree head angle, and even shorter, with 427mm chainstays, to create a bike that is nimble yet efficient. While the original F-Si used 135mm rear spacing, the newest version has updated Boost spacing with Cannondale’s Ai offset that allows for up to 2.35-inch-wide tires. While most cross-country racers will run a narrower tread, the added clearance will ensure no issues on muddy racecourses and trails. 

The first-generation F-Si had an impressively lightweight frame, but for this year Cannondale was able to shave 80 grams for a frame weight of 900 grams. To achieve this, Cannondale went with an integrated seatpost clamp and refined tube shapes for a balance of strength, stiffness and compliance. Keeping up with current trends, the F-Si frame is 1x-specific with a Press-Fit 30 bottom bracket and standardized tapered head tube. Cannondale also uses a flat-mount design for the rear brake to allow for easier adjustment and maintenance. 


The Lefty was initially introduced in 2000. It was a completely new approach to suspension design with a unique look that has become iconic over the years. Whether you are a believer in the technology or not, it has proven itself over the years. Cannondale has experimented with different versions of the Lefty—from cross-country to the longer-travel versions found on the Jekyll and Trigger trail bikes. Some versions were good and some were not so good. Now the eighth version of the Lefty is here with a completely new design. The Lefty has always had its own personality, and the Ocho is no exception.

 New for the Ocho is a completely redesigned damper that is smoother and lower maintenance than previous generations. With the help of suspension engineer Jeremiah Boobar, Cannondale developed its new Chamber damper and Delta Cage that combine needle bearings and bushings to create a fork that is more sensitive to small bumps and smoother throughout its travel. The Chamber offers an external compression adjustment with remote and rebound adjustments on the bottom of the fork leg. Cannondale also designed the Ocho with its new OppO air spring that has a self-balancing negative air chamber. 

Structurally, the Ocho takes a different approach from previous Leftys with a new industry-standard tapered steer tube. The previous generations used an oversized 1.5-inch steer tube that made stem choices and aftermarket frame conversions complex. While you still have to use a specific hub, the Ocho is compatible with most frames currently on the market. A large part of the F-Si is Cannondale’s Out Front geometry that revolves around the offset on the Ocho. While many brands are going with shorter fork offsets, Cannondale is sticking with 55mm on the Ocho. Cannondale first introduced this with its Scalpel-Si and has carried it over to the Ocho and F-Si. The Ocho is compatible with 27.5- and 29-inch wheels and comes with 100mm of travel.


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