Big moto performance. Bombproof durability. The new Sirris R38 shock brings real big-bike suspension technology to compact e-motos, using proven internal architecture shared with the larger R46 platform and an oversized chassis built for serious abuse. While other shocks in this class fade, leak, and fail, this one is engineered to keep charging. To accommodate the massive shock for smaller bikes, Sirris teamed up with Prickly to develop an R38 specific linkage (sold separately). Engineered for precise fitment and optimized geometry, this custom linkage raises the rear of the bike by 25mm to accommodate the 289×78 Sirris R38 shock. Note: the stock E-Ride Pro linkage WILL NOT WORK with the new R38 shock. CMX fork drop clamp can be added to raise the front by an equivalent 25mm. Sirris offers two weight ranges to choose from when selecting your R38 shock for E-Ride Pro SR. (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 = 90 N/mm spring) 180 lbs - 220 lbs (Heavy = 100 N/mm spring) PRODUCT SPECS: Architecture Piggyback, steel spring Stroke 78 mm Length 289 mm Weight 3.3 lbs / 1.5 kg without spring Adjusters 2SC = Two Stage Compression (Independent high-speed and low-speed adjust) • Tool-free low-speed compression adjust, 18 clicks • High-speed compression adjust, 24 clicks (20mm hex) • Tool-free rebound adjust, 24 clicks • Spring preload adjust Damping R38 shares the same high-flow base valve cavity architecture as the larger R46. Massive oil flow delivers true moto-level damping feel, control, and consistency. Pro-level CMX (Compact Motocross 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 each bike model and designed to pair perfectly with Sirris F43 CMX 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-spec internal floating piston system manages shaft displacement with precision, maintaining consistent damping feel under repeated hard hits and high heat loads. Shaft Same shaft as R46. 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 A new smaller diameter body, spring, retainers, and hardware package reduce overall size while preserving the oversized internal flow characteristics that define the shock’s ride quality. Seamless 6061 aluminum, type 3 hard anodized coating, ACME thread Piston The 38mm high-flow main piston uses true powersports architecture. Slightly smaller than the R46 piston but built with the same philosophy, it delivers massive tuning range and consistent damping performance far beyond anything in this category. 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 Body Cap New upper body cap engineered for tighter chassis fitment without sacrificing internal oil flow performance. Ultra-durable chrome plated, teflon-lined spherical bearings. Lower Eyelet New lower eyelet maintains maximum rebound oil flow to the shaft and metering rod while fitting smaller bike platforms. Ultra-durable chrome plated, teflon-lined spherical bearings. Bottom out MCU bumper Top out Rubber bumper Seals HNBR