FOX DHX2 Factory Coil Shock: Spring Rate and Setup FAQ

Quick answer

Set your DHX2 Factory up in this order: pick the spring rate for your riding weight and bike leverage, measure sag at the shock stroke, then tune low-speed compression and rebound. The DHX2 is a race-oriented coil shock with a wide adjustment range, so small changes go a long way.

Why spring rate comes before any dial turning

The DHX2 Factory is a coil shock, so the spring carries your weight and the damper controls how that energy is released. If the spring rate is wrong, no amount of compression or rebound adjustment will fix the ride: too soft and you sit deep in the travel, too stiff and you lose small-bump sensitivity. Use the FOX spring calculator as a starting point based on your weight and bike, then confirm with sag. The DHX2 does not include a spring, so order the rate you need separately.

How coil sag differs from air sag

On an air shock you set sag by changing air pressure. On the DHX2 you change sag by changing the spring rate or preload. Preload is for fine-tuning ride height and should not be used to correct a spring that is far too soft. Measure sag with you in full riding gear in a standing attack position, using the shock stroke as your reference. A coil shock typically runs slightly less sag than an air shock, so do not force an air-shock sag number onto the DHX2.

What the DHX2 adjustments actually change

The DHX2 Factory offers a broad tuning range, and the adjustments are best changed one at a time on a familiar trail. Low-speed compression affects how the shock holds up under rider input and in berms; high-speed compression affects how it handles square edges and big hits; rebound controls how quickly the shock returns after a bump. Make one change, ride the same section, and note the difference. The goal is a shock that stays composed without feeling harsh or packing down.

Coil vs air for downhill: the honest trade-off

A coil shock like the DHX2 Factory is chosen for sensitivity and consistency on long, rough descents, where the spring rate does not change as the shock heats up. The trade-off is weight and the need to buy the correct spring. An air shock is lighter and easier to adjust for rider weight, but it relies on a sealed air spring and can feel less planted in chunder. If your downhill riding is lift-served or steep and repeated, the DHX2's coil feel is the reason to choose it; if you pedal up and want quick setup changes, an air shock may suit you better.

DHX2 Factory setup FAQ

How do I choose a spring rate for the DHX2 Factory?

Start with the FOX spring calculator using your riding weight and bike model, then confirm with sag. If sag is far from your target, change the spring rate rather than adding heavy preload. The DHX2 does not include a spring, so the rate is a separate purchase.

How do I measure sag on a coil shock?

Put on your riding gear and stand on the pedals in attack position. Slide the bumper against the shock body, step off gently, and measure how far the bumper moved. Compare that to the shock stroke, not the eye-to-eye length. Use the same method each time so changes are comparable.

What order should I adjust the DHX2 Factory?

Set spring rate and sag first. Then set rebound so the shock returns quickly but does not kick, followed by low-speed compression for support and high-speed compression for big-hit control. Change one dial at a time and record your settings. Return to your baseline if a change makes the ride worse; the wide range makes it easy to over-adjust.

Is the DHX2 Factory worth it over an air shock for downhill?

Choose it if you want coil sensitivity and consistent feel on repeated rough descents and accept the extra weight and spring purchase. Choose an air shock if you prefer lighter weight and tool-free spring-rate changes. Neither is universally better; match the shock to how you ride and climb.

Product facts

• FOX DHX2 FACTORY: Coil spring not included. You must choose and order the correct spring rate separately, so factor that into your setup plan.

  

• FOX DHX2 FACTORY: Super low-friction internals. That reduces stiction, which is why sag and small-bump feel respond clearly to spring and damper changes.
• FOX DHX2 FACTORY: Massive overall tuning range. You can fine-tune compression and rebound to your terrain, but make one adjustment at a time to avoid losing your baseline.