Argon 18

EQU.S.375B.3.2

Argon 18 Equation Shimano 105

$2,899.00
Size: S
Color: Podium Champagne
Free Shipping $100+ (bikes/frames exc.) 14 day return window
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Pickup available at Brimstone Bicycles Shop

Usually ready in 2-4 days

Description:

Argon 18 Equation — Carbon Endurance Road Performance With Everyday Value

The Argon 18 Equation is built for riders who want a fast, comfortable, value-packed carbon road bike for long rides, training, group rides, and all-day pavement adventures. It brings Argon 18's performance DNA into an approachable endurance-road platform with intuitive handling, SRS internal cable routing, 32c tire clearance, a 27.2mm round seatpost, fender mounts, and size-specific geometry.

Designed around comfort and confidence without giving up speed, the Equation is ideal for riders who want a refined carbon frame, stable endurance geometry, modern disc-brake performance, and reliable Shimano road components.

Why buy the Equation?

  • Carbon endurance road frame with Argon 18 ride quality
  • Comfortable geometry for long rides, fondos, and daily training
  • 32c tire clearance for rough pavement and added comfort
  • SRS cable routing for a clean cockpit and modern appearance
  • 27.2mm round seatpost for comfort and easy future upgrades
  • Fender mounts for seasonal flexibility
  • Argon Fit System and 3D System for better size-specific positioning

Why choose the Shimano 105 build?

The Shimano 105 build is available in Podium Champagne and Matte Charcoal.

The Shimano 105 build is the best-value Equation option. It is ideal for riders who want a dependable mechanical drivetrain, hydraulic disc braking, DT Swiss E1800 wheels, and the same Equation carbon frame platform at the lowest MSRP in the lineup. Choose it for simple serviceability, strong component reliability, and excellent price-to-performance.

Which Equation build should you buy?

Build Best For Why Choose It
Shimano 105 Di2 Riders who want electronic shifting at a strong value Choose 105 Di2 if you want fast, consistent electronic shifting, a clean modern road-bike feel, and the same Equation carbon frame platform at a lower price than higher-tier electronic road bikes.
Shimano 105 Riders who want the lowest entry price into the Equation platform Choose Shimano 105 mechanical if you want a durable, straightforward, service-friendly road bike with the same endurance geometry, 32c clearance, SRS cable routing, and value-focused carbon frame.

Specifications

Component Group Component Specification
Frameset Frame Argon 18 Equation carbon road frame
Frameset Fork Equation-specific carbon fork
Frameset Headset FSA NO.69 SRS System
Frameset Cable Routing SRS internal cable routing
Wheels Wheels DT Swiss E1800 Spline 32mm
Wheels Tires Vittoria Zaffiro Pro 700x30c
Wheels Tire Clearance 32c / 34mm measured clearance
Drivetrain Front Derailleur Shimano 105 R7100
Drivetrain Rear Derailleur Shimano 105 R7100
Drivetrain Crankset Shimano 105 R7100 50/34
Drivetrain Chain Shimano 105 CN-M7100
Drivetrain Cassette Shimano 105 CS-R7100 11-34
Brakes Brakes / Shifters Shimano 105 R7120 hydraulic disc shifter/caliper set
Brakes Rotors Shimano SM-RT86, 6-bolt, 160mm front / 160mm rear
Other Handlebar FSA Vero Compact
Other Stem FSA OS-167 Omega Pro
Other Saddle Prologo Akero
Other Seatpost FSA Gossamer SB20 27.2mm

Geometry

Measurement Unit XXS
44-46
XS
47-50
S
51-53
M
54-56
L
57-59
XL
60-62
A Seat Tube Height cm 42.0 45.0 48.5 52.0 55.5 59.0
B Seat Tube Angle deg 75.5 74.9 74.3 73.7 73.1 72.5
C Head Tube Angle deg 70.3 71.3 72.0 72.0 72.0 72.5
D Top Tube Length cm 49.6 51.6 53.7 55.8 58.0 60.4
E Chain Stay Length cm 41.7 41.7 42.0 42.0 42.0 42.0
F Wheelbase cm 98.1 98.9 99.7 101.3 103.0 104.3
G BB Drop cm 8.0 8.0 7.8 7.8 7.5 7.5
H1 Head Tube Length 3D (0mm) cm 8.4 10.1 12.0 14.1 16.6 18.9
H2 Head Tube Length 3D (25mm) cm 10.9 12.6 14.5 16.6 19.1 21.4
I Stand Over Height cm 67.3 70.0 73.4 76.4 79.7 82.7
L Fork Length (Axle-to-Crown) cm 38.7 38.7 38.7 38.7 38.7 38.7
R Fork Rake cm 5.2 5.2 4.7 4.7 4.7 4.7
T Trail cm 6.8 6.1 6.2 6.2 6.2 5.9

Fit: Stack and Reach

Measurement Unit XXS
44-46
XS
47-50
S
51-53
M
54-56
L
57-59
XL
60-62
J Stack cm 51.8 53.7 55.8 57.8 60.0 62.3
J Stack 3D (25mm) cm 54.1 56.1 58.1 60.2 62.3 64.6
K Reach cm 35.9 36.9 37.9 38.8 39.7 40.7
K Reach 3D (25mm) cm 35.1 36.1 37.2 38.1 39.0 40.0
Saddle Height Min cm 56.0 59.0 62.5 66.0 69.5 73.0
Saddle Height Max cm 74.0 77.0 80.5 84.0 87.5 91.0

FAQ

What type of bike is the Argon 18 Equation?

The Equation is a carbon endurance road bike designed for riders who want comfort, stable handling, reliable components, and performance-road efficiency without moving into Argon 18's higher-priced race platforms.

Is the Equation good for long rides?

Yes. The Equation uses endurance geometry, a compliance-focused carbon layup, a 27.2mm round seatpost, and tire clearance up to 32c, making it well suited for long rides, fondos, training days, and rougher pavement.

What is the difference between Equation 105 Di2 and Equation 105?

The Shimano 105 Di2 model is the better choice for riders who want electronic shifting. The Shimano 105 mechanical model is the best-value option for riders who prefer a simpler, more affordable, mechanically shifted road bike.

How much tire clearance does the Equation have?

Argon 18 lists the Equation with 32c tire clearance, with a 34mm measured clearance reference.

Does the Equation use internal cable routing?

Yes. The Equation uses Argon 18's SRS cable routing and FSA NO.69 SRS headset system for a clean front-end setup.

Who should buy this bike?

Buy the Equation if you want a comfortable carbon road bike for training, endurance riding, group rides, and all-day road adventures, but do not need the more aggressive geometry or premium component price of a pro-level race bike.

What sizes are available?

This import includes XXS, XS, S, M, L, and XL variants. Missing size/color combinations are included with zero inventory so the product page can display the full size range without overstating stock.

Search-friendly summary: Argon 18 Equation Shimano 105 mechanical road bike with carbon endurance road frame, 32c tire clearance, disc brakes, SRS cable routing, fender mounts, and XXS through XL sizing.

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Return Policy

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