Whats this?

[Steve11]

[hornetrider]

Thats a remote reservior for what presumably is your rear shock, though its difficult to tell from the angle of the photo. Got a wider context?

[MTBR]

Part of the rear shock, sometimes called an external piggyback resevoir.
There is a small floating piston inside with pressurised gas one side and damping oil the other. This is connected to the main body of the shock so that the oil in the shock is also under pressure.
Pressurising the oil helps prevent foaming, the canister also increases the total volume of oil. As a result the shock is more consistent and runs a bit cooler.

[Chilli]

Tis indeed. They also get very hot when you've been caning it around for a while!!!

[Steve11]

Just relaised the pic should be turned 90 deg clockwise .... thanks Guys

[biker's nemesis]

Rear shock reservoir off a honda CBR 600 RR. 2003-2006.



ETA: Ahh, it's off your own bike.

Edited by biker's nemesis on Wednesday 6th June 11:12