Motorcycle Shock Reservoir Hose Union Seals

Some motorbikes don't have room for a piggyback canister built onto the shock absorber body, but would still benefit from the extra oil capacity & nitrogen bladder that a piggy back container would hold - find out more about different shock styles. So some aftermarket rear shocks (and a handful of rare OEM dampers) use separate reservoirs, away from the main shock body, connected by a hydraulic hose. It's not just about space saving either - remote canisters mounted out in the air flow can cool the oil better for consistent damping even during offroad enduro racing.

Those reservoir hose connection joints need to be sealed effectively from the high oil pressure, so at each end you'll find union seals - either a soft Aluminium Alloy or Copper metal flat washer, or Bonoco (Dowdy) Sealing Washers which features a rubber lip on the inner diameter.

If you're rebuilding one of these exotic race-bred shocks, you should have a look in our Shock Upgrade Parts to see how you can tune it even further, or if you don't own a Rebound, Slow Compression & Fast Compression Adjustable Shock Absorber you should have a look at ours - they offer the ultimate in adjustability.

A quick note for people shipping their suspension to a workshop for servicing too: don't separate the seals on the coilover! It's under serious pressure and means your package goes through the mail soggy and leaking oil no matter how much you think you've drained it - see our FAQ on shipping suspensions.