The Fox 38 Factory GRIP2 has earned a reputation among aggressive trail riders and enduro racers for its exceptional control, tunability, and stiffness. Engineered for demanding terrains and heavier-duty riding, this fork brings precision to the forefront. Built around a 38mm chassis and the highly regarded GRIP2 damper, it stands out in the Fox lineup for its robust performance and advanced adjustability.

Tools Required

• Torque wrench [paid link] (Nm specific for axle and crown bolts)
• Allen wrenches [paid link] (4mm, 5mm, 6mm)
• Suspension grease and shock pump
• Isopropyl alcohol and clean rags
• Suspension oil (Fox 20wt Gold or as specified by Fox)
• Seal driver kit
• Flat blade screwdriver or pick for seal removal

Installation Process

Proper installation of the 38 Factory GRIP2 fork ensures safe and optimal function. Begin by verifying steerer tube compatibility with your bike’s headtube. The 38’s steerer is tapered (1.5” to 1 1/8”), compatible with most modern enduro frames.

Insert the steerer tube through the headset, ensuring bearing preload is correctly adjusted via the top cap. Tighten the stem bolts to manufacturer torque specifications. Secure the thru-axle (15QR x 110mm Boost) once the front wheel is properly seated.

Brake caliper installation should be done using post-mount adapters if necessary, depending on rotor size. Carefully align the caliper to avoid rotor rub, tightening caliper bolts incrementally while squeezing the brake lever to center the pads.

Adjustment and Setup

The Fox 38 Factory GRIP2 offers high levels of customization, primarily through its GRIP2 damper and air spring.

GRIP2 Damper Tuning

The GRIP2 provides four-way damping adjustment:

• High-speed compression (HSC) and low-speed compression (LSC)
• High-speed rebound (HSR) and low-speed rebound (LSR)

For baseline settings, refer to Fox’s rider weight chart. Typically, compression adjustments help balance support and compliance, while rebound controls return speed after compression. LSC and LSR affect ride feel over small bumps and in technical terrain, while HSC and HSR tune response to larger hits and landings.

EVOL Air Spring Setup

The EVOL air spring on the 38 offers plush initial travel and a progressive mid-stroke. Set sag to approximately 20–25% by adjusting air pressure via the Schrader valve on the left leg. Volume spacers can be added to increase progressivity if bottoming out frequently, or removed for a more linear feel.

Maintenance Requirements

Routine maintenance keeps the 38 Factory GRIP2 functioning smoothly and prevents premature wear. Fox recommends 40-hour lower leg service intervals and full damper rebuilds at 125-hour intervals or yearly.

Clean fork stanchions after every ride. Avoid pressure washing near seals. Use isopropyl alcohol to wipe seals and stanchions, and inspect for oil residue or damage. During lower leg service, replace wiper seals and foam rings, inspect bushings for play, and refill with correct oil volumes.

Troubleshooting Common Set-Up Issues

Several common setup mistakes can impair performance.

Harsh ride quality often stems from too much HSC or insufficient sag. Reduce HSC and check air pressure to improve small-bump sensitivity.

Brake dive may indicate excessive LSC. Increase LSC incrementally to balance support without compromising traction.

Packing down through rough terrain usually means rebound is too slow. Loosen LSR (and HSR if needed) until the fork recovers between hits.

If top-out clunk is heard, verify air pressure and check that rebound isn’t set too fast.

Customization and Optimization

Personalization is a key strength of the GRIP2-equipped 38 Factory. Riders can fine-tune performance through:

• Volume spacers: Adjust end-stroke ramp-up without changing spring rate.
• Aftermarket decals and bolt kits: Add personal aesthetic touches.
• Upgrading to Kashima-coated stanchions (standard on Factory model): Enhances durability and smoothness.

Heavier or more aggressive riders may benefit from increasing air pressure and compression damping, while lighter or more playful riders can tune for more suppleness.

Compatibility With Other Drivetrain Components

The Fox 38 Factory GRIP2 fork is neutral in terms of drivetrain compatibility but requires consideration of axle standards and brake mount types.

It accepts 15×110 Boost front hubs, common on modern trail and enduro bikes. Rotor compatibility supports 180mm minimum rotors, with adapters allowing up to 203mm setups. Ensure front wheel and brake setup are compatible to maintain optimal braking and steering precision.

The fork is not affected by derailleur or chainring choices, but headset type must match its tapered steerer.

Model Comparison: 38 Factory GRIP2 vs. Competitors

When compared to alternatives like the RockShox ZEB Ultimate or Öhlins RXF38, the Fox 38 Factory GRIP2 often leads in small-bump compliance and fine-tuning adjustability.

• ZEB Ultimate offers a slightly stiffer chassis but fewer damper adjustments (Charger 3 has three vs. GRIP2’s four-way).
• Öhlins RXF38 impresses with plushness but is heavier and less tunable.
• Fox 36 is lighter but lacks the chassis stiffness of the 38, making it less suited for aggressive enduro racing.

The 38 Factory is best suited for riders prioritizing descending performance and extensive tuning options.

Frequently Asked Questions

Q1: What is the recommended air pressure for the Fox 38 Factory GRIP2?
A1: Air pressure varies by rider weight. Refer to Fox’s setup chart, but typically ranges from 60 psi for lighter riders to over 100 psi for heavier ones.

Q2: How often should I service the 38 Factory GRIP2?
A2: Perform lower leg service every 40 riding hours, and a full damper and air spring service every 125 hours or annually.

Q3: Can I use the 38 GRIP2 on an e-MTB?
A3: Yes, the 38 is e-MTB rated and ideal for the added weight and stress of electric mountain bikes.

Q4: What rotor sizes are compatible with the Fox 38?
A4: The minimum rotor size is 180mm, and adapters are available for 200mm or 203mm setups.

Q5: How do I fix a spongy feel in my fork travel?
A5: This may be due to inadequate air pressure, dirty seals, or worn internal components. Check pressure, clean seals, and consider a service if issues persist.

Q6: What makes the GRIP2 damper better than simpler models?
A6: GRIP2 allows four independent adjustments for compression and rebound, offering unparalleled tuning capability for various terrain and rider preferences.