The Fox 34 Performance fork is a mid-travel suspension fork designed specifically for trail riders who demand performance, reliability, and efficiency on diverse terrain. With its optimal balance of weight, stiffness, and tunability, the 34 Performance excels in fast, technical trail environments. This guide provides a comprehensive breakdown of installing, adjusting, maintaining, and optimizing the Fox 34 Performance, along with troubleshooting tips, compatibility guidance, and a comparison to similar models.
Tools Required
- 5mm and 6mm hex wrenches
- Torque wrench [paid link] with Nm scale
- Crown race setting tool
- Shock pump (for air pressure tuning)
- Suspension grease
- Allen keys [paid link] (various sizes)
- Torque wrench [paid link]
- Isopropyl alcohol and clean cloths
Installation of the Fox 34 Performance
Proper installation ensures structural integrity and optimal fork performance. The Fox 34 Performance is available with a tapered steerer tube and fits 29-inch or 27.5-inch wheels depending on the specific variant.
Steerer Tube Preparation and Crown Race Fitting
Before cutting the steerer tube, measure twice with your headset and spacers in place. Use a pipe cutter or fine-tooth hacksaw, then chamfer the edge to prevent wear. Fit the crown race with a setting tool to ensure alignment and tight fitment without damaging the bearing seat.
Star Nut or Compression Plug Installation
For aluminum steerers, a star nut is typically used. Insert it using a dedicated tool, aligning it at a 10-15mm depth. For carbon steerers, use a compression plug, ensuring even preload.
Headset Assembly and Torque
Install the fork into the head tube, align spacers and stem, and torque the top cap bolt just enough to eliminate play. Finish by tightening the stem bolts to 5-6 Nm, ensuring even clamping.
Brake and Axle Interface
Use a post-mount adapter if required for larger rotors. Center the caliper over the rotor before torquing bolts. Insert the thru-axle and torque it to 12-15 Nm. Check wheel centering and rotor clearance.
Adjusting the Fox 34 Performance for Optimal Performance
The Fox 34 Performance comes with a FIT GRIP damper and EVOL air spring, both designed for broad tunability.
Setting Air Pressure
Use the rider’s weight in gear to determine baseline air pressure. Fox provides a chart for reference. Add air with a shock pump and confirm sag is around 25-30% of total travel.
Rebound Damping Adjustment
Use the red dial at the bottom of the right fork leg to fine-tune rebound. Begin with the factory midpoint setting and adjust based on rider feedback. Too fast causes pogoing; too slow leads to poor traction recovery.
Compression Damping via FIT GRIP
The top dial on the right leg adjusts low-speed compression. For technical trails with lots of hits, keep compression low for suppleness. For climbing, add compression to maintain support and minimize bobbing.
Maintenance Requirements and Intervals
Maintaining the Fox 34 Performance extends its life and keeps performance consistent.
Lower Leg Service (Every 30-50 Hours)
Remove the lowers, clean out old oil, and inspect the foam rings and seals. Replace if worn. Apply fresh suspension-specific grease to seals and reassemble with correct bath oil volume (typically 10cc per leg).
Full Damper and Air Spring Overhaul (Every 100-125 Hours)
This service involves disassembling the damper and air spring. Replace O-rings and seals as specified in Fox’s service kit. Bleed the damper using the recommended fluid and vacuum method for best results.
Inspection and Torque Checks
Regularly inspect for stanchion wear, crown creaks, and axle interface tightness. Retorque crown bolts (if applicable), brake mounts, and axle to factory specs.
Troubleshooting Common Set-Up Issues
Riders may encounter performance irregularities after installation or tuning.
Inconsistent Travel or Harshness
This often stems from incorrect air pressure or poor sag setup. Recheck with full gear and adjust as needed. Also verify that the negative spring has equalized via the reset procedure (compress fork deeply once).
Excessive Stiction or Lack of Small Bump Sensitivity
This usually indicates dry or dirty seals. Perform a lower leg service and ensure foam rings are saturated. Use only Fox-approved suspension oil.
Brake Rub or Rotor Misalignment
Ensure calipers are mounted square and the thru-axle is properly torqued. Wheel dish should also be verified if rub persists.
Customization and Tuning Options
Beyond factory settings, the 34 Performance can be customized to meet specific rider needs.
Volume Spacers
Adding volume spacers increases progression, ideal for aggressive riders who bottom out too easily. Removing them softens end-stroke ramp, useful for lighter riders or those preferring linear feel.
Aftermarket Seals and Lubricants
Upgrading to SKF low-friction seals can reduce breakaway force and improve small bump compliance. Switching to higher-quality bath oils like Fox 20wt Gold enhances long-term performance.
External Adjustments and Tokens
Install compatible tuning tokens or aftermarket compression knobs for better ergonomics or tactile feedback during rides.
Compatibility with Other Drivetrain and Cockpit Components
The Fox 34 Performance must be paired with appropriate drivetrain and cockpit components.
Rotor Size and Brake Compatibility
Accepts rotors from 160mm to 203mm, depending on brake caliper and adapter compatibility. Ensure calipers align with post-mount spacing (74mm).
Headset and Frame Compatibility
Designed for tapered head tubes (1.5” to 1-1/8”), and accepts most integrated or external headset systems. Verify frame crown race diameter and steerer tube insertion length.
Handlebar and Stem Sizing
Use 31.8mm or 35mm stems with proper torque. Ensure enough steerer tube protrudes to accommodate bar height and rider preference.
Comparing the Fox 34 Performance with Similar Models
When selecting a trail fork, it’s helpful to contrast features and benefits with other forks.
Fox 34 Performance vs. Fox 34 Factory
The Factory version includes the FIT4 or GRIP2 damper and Kashima-coated stanchions. While both offer excellent stiffness and weight, the Performance version prioritizes value with nearly the same chassis but fewer adjustments.
Fox 34 Performance vs. RockShox Pike Select
The Pike Select offers DebonAir spring and Charger damper. The 34 Performance is generally lighter and slightly more supportive off the top, whereas the Pike offers plusher mid-stroke support.
Fox 34 Performance vs. Marzocchi Z2
The Z2 shares some internals but is heavier and uses a different damper design. The 34 Performance offers better tunability and a stiffer chassis for aggressive trail use.
Frequently Asked Questions (FAQs)
Q1: What wheel size is compatible with the Fox 34 Performance?
The fork is available for both 27.5-inch and 29-inch wheels. Verify the specific model variant before purchase.
Q2: Can I upgrade from the FIT GRIP damper to FIT4 or GRIP2?
No, the chassis is not compatible with FIT4 or GRIP2 due to internal differences in damper size and routing.
Q3: How many volume spacers come pre-installed?
Most 34 Performance models come with one or two spacers, depending on travel. Refer to Fox’s tuning guide for exact counts.
Q4: Can I install the fork on a hardtail frame?
Yes, as long as the axle-to-crown measurement and rake are within the frame manufacturer’s approved limits.
Q5: Does the Fox 34 Performance support e-bike use?
Some variants are e-bike rated. Look for the specific e-MTB designation when purchasing.
Q6: Is the stanchion coating different from the Factory version?
Yes, the Performance uses a black anodized finish, while Factory uses Kashima. Performance is slightly less slippery but still highly durable.
Conclusion
The Fox 34 Performance is a robust, trail-specific suspension fork engineered for precision and dependability. It offers a refined balance of comfort, control, and efficiency, making it a worthy upgrade for riders seeking trail-optimized performance without the premium cost of Factory models. With proper setup, maintenance, and occasional tuning, it consistently delivers confidence-inspiring trail handling across varied terrain.