Sirris F43 Fork Spring (Single) | By Sirris Suspension | For F43 Forks on E-Moto Platforms
Fine Tune Your Front Suspension the Right Way
At REV Rides we always tell riders that suspension performance starts with the correct spring rate. The Sirris F43 Fork Spring allows riders to dial in their suspension setup to match rider weight, riding style, and bike configuration. These springs are designed specifically for Sirris F43 forks and are available in multiple rates so you can properly balance your suspension for maximum performance.
Unlike many forks, the F43 platform allows riders to run different spring rates in each leg to achieve an exact combined rate. This makes it possible to create a perfectly tuned setup without compromising overall fork performance. Whether you are upgrading components, adjusting for rider weight, or fine tuning your suspension for racing or trail riding, the correct spring rate makes a huge difference in traction, stability, and control.
Why Proper Fork Spring Setup Matters
Improves front-end traction and stability
Maintains correct suspension sag for balanced handling
Optimizes damping performance from your F43 fork
Allows precise tuning for rider weight and riding style
Supports heavier upgrades such as larger batteries or performance components
Technical Specifications
Spring Length: 445 mm
Inner Diameter: 29.6 mm
Compatible Fork: Sirris F43 forks
Sold As: Single spring (two required per fork set)
Available Spring Rates
3.2 N/mm
3.6 N/mm
4.0 N/mm
4.4 N/mm
4.8 N/mm
5.0 N/mm
5.4 N/mm
5.8 N/mm
Spring Rate Tuning
F43 forks allow riders to run two different spring rates to achieve an in-between combined rate. This gives riders more flexibility when dialing in suspension performance.
Example: A common Sur-Ron Trail Medium setup averages 4.6 N/mm. This is achieved by installing a 4.4 N/mm spring in one leg and a 4.8 N/mm spring in the other. The result is a balanced combined spring rate without requiring custom springs.
Setup Notes
Two springs are required per fork set
Different spring rates can be combined to achieve an in-between rate
Oil levels and clicker settings should remain the same on both fork legs
No separate tuning is required when running two different spring rates
Fitment
Sirris F43 Forks
Commonly used on Sur-Ron, Talaria, E-Ride Pro, Ventus, and other compact e-moto platforms using the F43 fork
Ideal Riders for This Upgrade
Riders dialing in suspension for specific rider weights
Builders upgrading to heavier batteries or performance components
Anyone fine tuning their Sirris F43 suspension setup for maximum performance
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