MTB fork seal kits

How to choose your MTB fork seal kit

A fork that sticks at the start of travel, weeps oil or has lost its suppleness is rarely worn out: it just has tired seals and degraded oil. A kit costing a few tens of pounds will restore its original performance.

Dust wiper kit or full kit?

• Dust wiper seal kit : the two visible seals at the top of the lowers, plus the foam rings that hold lubricating oil. This is the 50-hour service, which can be done at home in an hour.
• Full seal kit : dust wipers, internal seals, damper and air spring O-rings. This is for the annual or 200-hour service.
• 200-hour service kit : sold by fork model, it includes everything needed for a full service, with nothing left out.

Identifying the right kit

• The model and generation of the fork (A1, B1, C1…): this is why orders go wrong nine times out of ten.
• Stanchion diameter : 30, 32, 34, 35, 36, 38 or 40 mm.
• The brand : RockShox, Fox, Marzocchi. SKF kits fit several Fox and Marzocchi forks and often offer lower friction than original seals.
• The model year, indicated on the fork decal or in the part number etched on the lower leg.

When to service

• A oil film running down the stanchions after every ride.
• A fork harsh at the start of travel, sticking over the first few millimetres.
• A squelching sound or friction under compression.
• As a rule: 50 hours of riding for dust wipers, 200 hours or one year for a full service. Halve these intervals if you mostly ride in muddy conditions.

Oil matters just as much as seals

When reassembling, use the recommended bath oil volume and viscosity for your model. Too much oil and the end of the travel hits a hydraulic wall; too little and the guide bushings run dry, damaging the stanchions — irreversible damage.

To find out more: How to service your MTB fork

See also: Fork cartridges and spare parts · Shock seals and bushings · 29-inch MTB forks