Description
SIRRIS F43 CMX TUNE
RIDE IT ONCE.
REGRET EVERYTHING ELSE.
F43 CMX
THE WORLD’S BEST COMPACT
E-MOTO FORK. PERIOD.
An oversized, race-built F43 chassis paired with our CMX-tuned closed cartridge damper — built for elite control, razor-sharp handling, and unreal front-end confidence. This is the strongest, most durable, highest performance fork available.
You need to ride it to believe it.
It’s that good.
SPRING RATES
Sirris offers two weight ranges when selecting your CMX Tune F43 fork for Zero XB. (Listed weight ranges are rider weight without riding gear on. 15 pounds of riding gear is calculated into the weight ranges)
140 lbs - 180 lbs (Medium = 3.6/3.2 springs)
180 lbs - 220 lbs (Heavy = 3.6/3.6 springs)
Fork spring rates listed above are left side/right side.
Installation Guide:
TOOL-FREE COMPRESSION ADJUSTERS
NEW FOR CMX — Allows for quick compression adjust without a screwdriver.
Enjoy nearly 30 clicks of quick external adjustability.
DIRECT MOUNT STEM
DM READY — New CMX fork is designed with a Direct Mount (DM) setup, so the stem you’re already using will bolt right up—no hassle, no extra parts.
DROP CLAMP OPTION
BIG WHEEL OPTIONAL — Allows for fitment of 21” wheel by raising the front end an additional 25mm while retaining 220mm travel. (Raising the front end maintains balance of the bike if paired with a longer shock that raises the rear)
NEW AXLE & BRAKE MOUNTS
ULTRA STIFF AND CONFIGURABLE — Axle and drop out assembly promotes front end feel and steering precision. Replaceable caliper mount brackets allow for caliper upgrades.
FORK SPECS:
Architecture
Upside down fork
Travel
220 mm
Free length
775 mm
(drop clamp option adds another 25mm of extended length)
Fork Spacing
178 mm - allows for unlimited tire choice (dirt or street)
Fork weight
4 kg per leg (driven by sturdy construction required for the forces and speeds encountered when pushing these bikes to their limits without compromising performance)
Stanchions
Ø43, high tensile steel with hard chrome
Outer tubes
Seamless 7050 aluminum, type 3 hard anodized coating
Drop outs
6061 aluminum, type 2 anodized coating
Replaceable caliper mount brackets allow for caliper and wheel upgrades
Axle
Ultra-high tensile hard chromed axle increases steering precision and confidence
Triple clamps
Billet 6061 aluminum, type 2 anodized coating, 2 color options (blue, black)
Optional drop clamp allows for 21” front wheel conversion (black only)
Steer tube
Seamless 7050 aluminum, type 2 anodized coating
Damping
Symmetrical, adjustable closed cartridge with spring backed modified IFP
Damper bodies
Seamless 7050 aluminum, type 3 hard anodized coating
Rebound
Dual side high tensile steel spring, adjustable
Adjusters
External tool-free compression, rebound adjustment
(rebound adjusted using tool)
Seals
NOK MX seals
Bushings
Daido MX bushings
Guards
High impact PP, 210-degree wraparound
