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Cannondale F-Si Carbon 4 2021 Mountain Bike

About the product This product is now out of stock



About the productCannondale F-Si Carbon 4 Hardtail Mountain Bike, In Alpine 2021

Fast, agile and snappy is how we’d describe Cannondale’s F-Si Carbon 4. This all-carbon hardtail mountain bike is a true weapon and just as fast up the hill as it is down the hill. With a racing-oriented geometry and choice of components that is catered to creating a lightweight racing machine, the 2021 F-Si Carbon 4 is one of the fastest mountain bikes in Cannondale’s range.


Detailed explanation

The BallisTec Carbon frame comes with a tapered headtube and a Speed Release thru-axle at the rear. Paired with the Lefty Ocho 100mm fork, this is one of the lightest frameset combinations out there, and it’s completely geared towards racers. Cannondale’s Wheel Sensor also gets you a speed, route and distance info by connecting to your phone.

The drivetrain is a combination of SRAM’s SX and NX Eagle series for shifting, and Shimano’s excellent MT500 hydraulic disk brakes. It’s a 1x12 drivetrain with a wide range cassette at the rear and a 34T chainring at the front, which is simple but works very well.

The wheels are a lightweight combination of WTB’s STX rims with a 23mm internal width and a tubeless-ready design, and Schwalbe tyres. Both come with an Addix compound, which sticks to dry surfaces and allows you to push the F-Si Carbon 4 as hard as you can and beat those Strava times, both up and down the hills.

And even though this is a racing bike, you still get a pair of comfortable grips and saddle that come in handy when you’re doing longer training sessions. Overall, the 2021 F-Si Carbon 4 is a true racing weapon that you’ll love.


Technical features:

  • BallisTec Hi-Mod Carbon frame is an extremely lightweight frame with excellent stiffness, strength and durability.
  • SAVE micro-suspension in the rear triangle give the frame shock absorption to increase comfort and greatly improve traction.
  • Integrated wheel sensor that shows you accurate speed, distance and route info, and reminds you when your bike needs service.
  • 1x12 drivetrain is simple and reliable, yet has you covered in just about any scenario.
Great customer service from Damian Harris Cycles, always on the other end of the phone if I needed.


CATEGORYMountain Bike
AVAILABILITY Out of stock, please call for availability
Model Number C25501M
Model NameF-Si Carbon 4
FrameBallisTec Carbon, SAVE, PF30-83, tapered head tube, Speed Release 12mm thru axle, Ai Offset
ForkLefty Ocho, 100mm, Chamber Damper with remote lockout, OppO Spring System, tapered steerer, 55mm offset
RimsWTB STX i23 TCS, 32h, tubeless ready
Hubs(F) Lefty 60 / (R) Shimano MT400 12x148mm thru-axle
SpokesDT Swiss Competition
Tires(F) Schwalbe Racing Ray Performance, 29 x 2.25", Addix Compound, tubeless ready, (R) Schwalbe Racing Ralph Performance, 29 x 2.25", Addix Compound, tubeless ready
CrankSRAM X1-1000 Eagle DUB, 34T, Ai offset
Bottom BracketSRAM DUB PF30 MTB83
ChainSRAM SX Eagle, 12-speed
Rear CogsSRAM SX Eagle, 11-50, 12-speed
Rear DerailleurSRAM NX Eagle
ShiftersSRAM NX Eagle, 12-speed
HandlebarCannondale 2 Flat, butted 2014 Alloy, 31.8mm, 3-deg rise, 8-deg sweep, 760mm
GripsFabric FunGuy
StemCannondale 3, 6061 Alloy, 31.8, 7-deg
HeadsetIntegrated, 1-1/8 to 1.5", sealed angular contact bearings (Integrated steer stop size small and extra small only)
BrakesShimano MT500 hydraulic disc, 160/160mm RT54 rotors
Brake LeversShimano MT500 hydraulic disc
SaddleFabric Scoop Shallow Sport, steel rails
SeatpostCannondale C3, 6061 Alloy, 27.2 x 350mm (S), 400mm (M-XL)
ConnectivityCannondale Wheel Sensor

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Size guide

Mountain bike sizing chart (Mountain bike)
Feet and Inches Centimetres Inches Size
4' 10" - 5' 2" 148 - 158 13 - 14 XS
5' 2" - 5' 6" 158 - 168 15 - 16 S
5' 6" - 5' 10" 168 - 178 17 - 18 M
5' 10" - 6' 1" 178 - 185 19 - 20 L
6' 1" - 6' 4" 185 - 193 21 - 22 XL
6' 4" - 6' 6" 193 - 198 23 - 24 XXL
Women's mountain bike sizing chart (Mountain bike)
Feet and Inches Centimetres Inches Size
4' 10" - 5' 2" 148 - 158 13 - 14 XS
5' 2" - 5' 6" 158 - 168 15 - 16 S
5' 6" - 5' 10" 168 - 178 17 - 18 M
5' 10" - 6' 1" 178 - 185 19+ L
Cannondale F-Si Carbon 4 Hardtail Mountain Bike, In Alpine 2021
Cannondale F-Si Carbon 4 Hardtail Mountain Bike, In Alpine 2021

Shipping & returns

Due to the size and weight of most bikes, a charge would apply to shipping remote regions, offshore UK and Ireland.

The courier will require a signature for your delivery. If no one is available to sign for your goods, the courier will leave a card with instruction of where you can collect it.

Working days are Monday to Friday unless otherwise stated. There may be circumstances beyond our control which cause delay and in such circumstances we will endeavour to deliver the goods as soon as they arrive from manufacturers.

Read more about our Shipping & Returns Policy, here.


Our flexible finance options mean you can purchase this product with a minimal deposit (or call us and arrange a deposit that suits you). Before applying for finance, please ensure you have read the information on eligability.

Apply for finance online through v12Finance

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