SIRRIS R46 TRAIL TUNE SHOCK FOR SURRON ULTRA BEE
Proven at the highest level. Built from real-world feedback.
R46 Trail Tune | 2SC | Surron Ultra Bee 1.2
MORE ADJUSTABILITY. MORE CONTROL.
Now with 2SC (Two Stage Compression), updated Trail Tune refinements, updated bumper, and new graphics.
Trail Tune is a very versatile and aggressive tune that is sporty and supportive, designed to go fast over a wide variety of terrain.
RIDER WEIGHT SPECS:
Sirris offers six weight ranges to choose from when selecting your Trail Tune R46 shock. (Listed weight ranges are rider weight without riding gear on. 15 pounds of riding gear is calculated into the weight ranges)
< 160 lbs (Light = 75 N/mm spring)
160-200 lbs (Medium = 85 N/mm spring)
200-230 lbs (Heavy = 95 N/mm spring)
230-260 lbs (X Heavy = 105 N/mm spring)
260-290 lbs (XX Heavy = 115 N/mm spring)
> 290 lbs (XXX Heavy = 125 N/mm spring)
PRODUCT SPECS:
Architecture
Piggyback, steel spring
Stroke
85 mm
Length
320 mm
Weight
3.9 lbs / 1.76 kg without spring
Adjusters
2SC = Two Stage Compression (Independent high-speed and low-speed adjust)
• Low-speed compression adjust, 18 clicks
• High-speed compression adjust, 24 clicks (20mm hex)
• Rebound adjust, 24 clicks
• Spring preload adjust
Damping
High-flow base valve cavity architecture. Massive oil flow delivers true moto-level damping feel, control, and consistency. Trail Tune damping with fully tunable compression and rebound circuits with high-flow internals that stay cool and consistent.
The result is exceptional pressure balance, faster frequency response, and a level of responsiveness normally reserved for full-size motocross suspension.
Tuned specifically for Surron Ultra Bee and designed to pair perfectly with Sirris F43 forks, it delivers unmatched balance, traction, and confidence at speed.
Reservoir
Specifically designed around the large 16mm shaft and high oil displacement demands. The massive R46 internal floating piston system manages shaft displacement with precision, maintaining consistent damping feel under repeated hard hits and high heat loads.
Shaft
Massive 16mm induction heat-treated hollow shaft with hard chrome finish — delivers extreme structural strength and huge oil flow through the main piston for true moto-level damping performance.
Ø16 mm OD chrome-plated, induction hardened steel, hollow, Ø 5.5 mm ID
Shock body
Seamless 6061 aluminum, type 3 hard anodized coating, ACME thread
Piston
High-flow main piston uses true powersports architecture, it delivers massive tuning range and consistent damping performance.
Ø46 mm, CNC 6061 billet aluminum, type 3 hard anodized coating
Piston band
Hard band
Spring retainer
Seamless 6061 aluminum, type 3 hard anodized coating, ACME thread, with locking feature, manual adjust
Bottom out
MCU bumper
Top out
Rubber bumper
Seals
NBR
The R46 receives an equally focused evolution, led by the introduction of Sirris 2SC—Two-Stage Compression—across the Trail, MX, and SX platforms. Two independent compression adjustments give riders significantly more control over how the shock responds to different types of terrain and impacts.
Low-speed compression allows riders to fine-tune chassis support and control during slower suspension movement, while high-speed compression manages the rapid shaft movement generated by jump landings, whoops, square-edge hits, and sharp impacts.
The result is greater adjustability and more ability to tune the Ultra Bee exactly to the rider, terrain, and riding style—while maintaining the controlled, connected ride feel Sirris is known for.
Isolation Explained
2SC independent adjuster architecture is engineered to maximize sealing integrity, prevent oil bypass, and eliminate piston back-off under high loads.
By isolating adjuster movement from the piston assembly and maintaining high o-ring preload without excessive adjuster torque, the system delivers long-term durability, damping consistency, and robust performance beyond conventional high-speed compression designs.
- Non-translating high-speed and low-speed adjusters prevent piston assembly rotation for enhanced long-term durability and reliability.
- Avoids the harshness and ineffective tuning commonly associated with traditional high-speed adjusters.
- Carefully engineered high-speed circuit minimizes the typical side effects found in conventional designs.
The Trail tune also receives spring-rate refinement, with updated spring rates and clicker settings designed to improve overall balance with the Ultra Bee's linear rear suspension linkage.
NEW BUMPER: The Trail Heavy and higher-weight applications receive a new bumper designed around this updated system, providing a more balanced end-of-stroke feel and improved control through the final portion of travel.
Trail Light and Medium configurations retain the current bumper.
TUNING DETAILS & RIDER WEIGHT RANGE
Listed weight ranges are body weight without riding gear (15 pounds of riding gear is calculated into the weight ranges).
Weights of upgrades (battery, controller, etc) need to be added to rider weight.
TRAIL TUNE Starting point notes:
- This is the starting point based on feedback from test riders, customers, and calculations.
- All riders have 15lbs gear included the calculation
- Light and Medium weight classes have neutral riding position
- Heavy and higher weight classes have rear biased riding position meaning more rear support.
- Stock bike with 18/21, all other bike upgrades need to be added to rider body weight with a 2x upgrade weight.
- Shock preload must be adjusted to give correct rider sag.
- Aggressive/pro riders to consider +1 weight class and drop preload to get sag. Especially if in the upper range.
- Rider preference, riding style, and riding conditions may require a different setup.
- Calculations are only valid for stock Ultra Bee swing arm and linkage with stock ratio.
Example:
- 180lbs rider without gear, 10lbs gear, 20lbs controller/battery.
- Weight calculation 180+(10-15)+2x20 = 215.
- Neutral rider = Heavy tune
- Aggressive rider = Consider X Heavy tune
SETTINGS NOTE: Settings are number of clicks from the closed position (full clockwise). Once they are in the closed position, back them out (counter-clockwise) according to the number of clicks indicated in the chart above to get you to factory settings.
*OIL NOTE: Sirris uses Shell Tellus S2 VX15 (5wt) in the fork cartridge and Shell Tellus S2 VX68 (20wt) as the bath oil. These are cross compatible with other high quality 5wt and 20wt suspension fluids. Sirris uses a semi-synthetic 2.5wt oil in the shock that is also compatible with other high quality 2.5wt aftermarket suspension fluids. You can use 5wt/20wt oils of your preference, Lubefinder.com can be used to source the fork oils. KYB K2C can be used in the shock and has wide availability.
LOWERING KIT
The Sirris lowering kit drops both the front and rear of your Ultra Bee by 28mm vertically, creating a more accessible, confidence-inspiring ride without sacrificing performance.
TECH HELP
Suspension setup, owner's guide, tech help, warranty and more. Learn how to properly set up, use, and maintain your new Sirris suspension products.
