Cannondale F-Si

84/100
BikeRide Score
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Users (3 ratings)
100
Experts (4 reviews)
83
Cannondale F-Si
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Facts

Gender
Men, Women
Type
Cross Country, Mountain, Non-Electric
Release Year
2020
Brand
Cannondale
Wheel Size
27.5”, 29”
Number of Gears
12 (1x12)
Gearing Type
External Derailleur
Weight
18.50, 19.40, 20.02, 22.30, 25.20 lb
Suspension
Front
Brake Type
Disc: Hydraulic
Frame Material
Carbon Fiber

Summary of Reviews

We have read all expert and user reviews on the Cannondale F-Si. In summary, this is what cyclists think.

18 reasons to buy

  • The F-Si cornered with precision at high speeds, in racing situations.
  • It was deemed ‘striking’, ‘head-turning’ and ‘uniquely good-looking’.
  • Single-tined Lefty Ocho forks weighed only 51oz and handled large hits well.
  • Climbing was considered to be fast and efficient atop the F-Si.
  • A cable-actuated fork lockout system simplifies tuning and maintenance.
  • Powerful Shimano XT brakes impressed on the F-Si 2.
  • A slack 69° head-angle and 55mm fork offset gave a planted and agile ride.
  • New 1⅛ x 1.5 tapered headtubes were now compatible with standard steerers.
  • Asymmetrical rear stays allowed stiffer, symmetrical lacing of the rear wheel.
  • Tire clearance allowed for rubber up to 2.35” in width.
  • The Schwalbe Racing Ray / Racing Ralph combo was fast and grippy.
  • An integrated seat-clamp allowed extra seatpost flex and kept lines clean.
  • Testers reported direct power transference into the F-Si’s back end.
  • SRAM’s Eagle groupset was regarded as reliable and exacting in its operation.
  • The ‘stunning’ carbon chassis design featured internal cabling.
  • A steel Eagle NX Cassette on the F-Si 5 was heavier, yet resilient.
  • Internal cable routing was readied for dropper-post connection.
  • The rear wheel’s ‘Speed-Release’ thru-axle made removal quick and easy.

7 reasons not to buy

  • Experts agreed that descents on the F-Si demanded attention and skill.
  • The ‘Ai’ system means that rear wheel replacements must be very specific.
  • Many testers and owners were keen to see a dropper-post specced on the F-Si.
  • The single-tined Lefty Ocho fork requires a front wheel with a unique hub
  • One expert said the bike came across as jouncy on rugged terrain.
  • A tester was not dazzled by SRAM Level T brakes on the F-Si 3.
  • Fork offset, wide bars and long stems led to slightly twitchy handling that suited advanced riders.

Bottom line

Not a beginner’s bike, but definitely a great option for your first race bike. Years of refinement see Cannondale’s unique technical innovations coalesce into the cross-country beast that is the F-Si. The manufacturer’s iconic Lefty fork, in this ‘Ocho’ configuration, sports superior low-friction sensitivity to small impacts due to the use of needle bearings and a progressive air shock. This sensitivity is perceived as a characteristic of the bike’s racy demeanour. Asymmetric ‘Ai’ rear stays make for a stiffer rear wheel, while an unprecedentedly slack head-angle and 55mm fork offset aims at a stable yet nimble ride. What is the upshot of all this tech banter? The F-Si is a refined, high-performance machine that might be too much for beginners, but which is a proven winner at breakneck speed in challenging conditions. Complete bikes range from around $2K to over $10K, allowing entry on a range of budgets.

Expert Reviews

83/100 based on 4 rated expert reviews
Apply to become an expert
80
BikeRadar
Level 5 expert

Cannondale F-Si Hi-Mod World Cup Review

Level 5 expert

Uniquely-forked, arse-kicking, ultralight XC racer but not for the faint-hearted or under-financed.

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90
Cyclingnews
Level 5 expert

Cannondale F-Si Carbon 3 Review

Level 5 expert

It’s difficult to dispute the stealth, almost Darth Vader-like visage of the Cannondale F-Si… Power transfer is immediate, whether you’re seated or out of the saddle… The F-Si is a lively bike…

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92.5
Solo Bici
Level 1 expert

Cannondale F-Si Hi-Mod World Cup: Next Level [Spanish]

Level 1 expert

The F-Si remains an impetuous and somewhat nervous bike in the fastest descents . It’s very light and responds vehemently to any insinuation.

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78
Fiets
Level 5 expert

Review: Cannondale F-SI Carbon 5 [Dutch]

Level 5 expert

It is good to be able to report that this stripped down version gives the same quick impression as its much more expensive brother… the wheels are a lot heavier and the fork less stiff… but this is hardly a hindrance.

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Mountain Bike Action
Level 5 expert

Cannondale F-Si Carbon 3

Level 5 expert

If you’re looking to get your first serious mountain bike, the Cannondale F-Si Carbon 3 should be vying for your attention. Road riders looking to get dirty, look no further… a serious competitive weapon.

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SickBiker
Level 1 expert

New Cannondale F-Si Carbon Hardtail vs. Old F-Si. Which Is Really Better?

Level 1 expert

The A.I. is the best feature for me…the frame will be lighter… so yeah, the 2nd generation has been improved… Do you pay for the brand? …You pay a little bit… Scott will be lighter…

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The Radavist
Level 5 expert

A Cub House Built Cannondale F-Si Hi-MOD Throwback XC Bike!

Level 5 expert

…compared to other contemporary XC hardtails this bike has a slacked headtube, shortened chain stays, and some serious clearance for bigger tires… a super fun and diverse bike that is perfect for both racer weenies and shred dawgs.

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Bicycling
Level 5 expert

The Cannondale F-Si Carbon 2 is a Privateer Racer’s Dream

Level 5 expert

It has the heart and soul of a cross-country racer. The bike feels and performs its best at speed… the fork may seem harsh… But at speed, it’s supportive and precise.

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mtbr
Level 5 expert

Cannondale F-Si Throwback

Level 5 expert

I went back and forth between the F-Si and a more old-school geometry Viathon hardtail… Each time I hopped on the Viathon, I was struck by just how much more I felt like I was about to brake with my face…

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BikeRumor
Level 5 expert

Cannondale F-Si Hardtail & Lefty Ocho Fork on a World Cup XC Course

Level 5 expert

…a longer front end, slack head angle & lower trail combined with short 427mm chainstays… makes the bike do really well both picking through technical sections fast or slow, and still climbing & accelerating quickly.

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Fiets
Level 5 expert

In Depth: Cannondale F-Si HI-MOD [Dutch]

Level 5 expert

At the level of the average Dutchman and on the corresponding Dutch trails I can handle this hardtail perfectly. On a fixed route, the F-Si certainly challenges you to step up a gear.

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MtbCult
Level 3 expert

The Cannondale F-Si 2019 on the Route Albstadt [Italian]

Level 3 expert

The watchword to describe this MTB is certainly “reactivity”… We are talking about a racing vehicle and, as is normal, it is designed to go fast everywhere …

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MTB MAG
Level 5 expert

Cannondale F-Si LTD Edition Test [Italian]

Level 5 expert

It’s almost unique because of its long reach and relaxed head angle…

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banachbrothers
Level 1 expert

Cannondale F-Si SE 19′ XTR 12 Speed [Polish]

Level 1 expert
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MTB-News.de
Level 5 expert

Cannondale F-Si 2018: The fastest XC Hardtail in the World? [German]

Level 5 expert

…a thoroughbred race bike… small adjustments and optimizations bring the frame back to the top… Uphill, it’s definitely at its best. Downhill, it requires good riding technique and a certain amount of getting used to.

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Solo Bici
Level 1 expert

Cannondale F-Si Special Edition: An F-Si to Remember [Spanish]

Level 1 expert

[The Lefty Ocho fork] is sensitive and glued to the ground at all times . When we lock it out, it is firm, totally firm, which in the most extended climbs turns the F-Si into a superfast bike.

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MTBiker
Level 1 expert

Cannondale F-Si Carbon 3 – Hardtail With The Spirit Of The Formula [Slovakian]

Level 1 expert

…the unique fork and a number of innovative solutions… speak for themselves. If for nothing else, I would personally buy this bike because of the new “Lefty”, because riding with it is a real experience.

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bikeWorld.pl
Level 5 expert

Cannondale F-Si Carbon 3 (2019) [Polish]

Level 5 expert

Considering both the level of the frame and the equipment, the price is reasonable – we finally have a bike that belongs in the family of the fastest XC hardtails on the market.

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bikeWorld.pl
Level 5 expert

Cannondale F-Si Hi-MOD World Cup (2019) [Polish]

Level 5 expert

The Cannondale F-Si, as a racing hardtail, is close to perfect – it’s amazingly light and stiff.

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User Ratings

100/100 based on 3 ratings
  • 5 star
    100%
  • 4 star
    0%
  • 3 star
    0%
  • 2 star
    0%
  • 1 star
    0%

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