Reservoir fill

This procedure is somewhere between maintenance and a mod. I saw it when I was watching Fred's maintenance videos. When he increased the preload on his rear shock it didn't acutally start working until it was at '6'. I checked mine and it didn't start working until '5'. If you listen to the pump as you increase the preload you can hear the pump change tone when it actually starts pushing fluid. Fred had a trick to fill the pump reservoir so the preload starts working from '0'.

Note: If you plan to do maintenance on your bike I HIGHLY recommend purchasing Fred's videos. It makes doing a lot of the stuff to your bike much easier. I purchased his videos before I even had a Goldwing.

I'm going to hit the highlights of this procedure. For more detail get Fred's videos.


To access the preload pump you have to remove the seat and the right saddlebag. Make sure the preload is set to '0'.


To remove the pump disconnect two electrical connectors (blue arrows) and remove two bolts (red arrows).


With the pump removed you can disconnect the hydraulic line.


Keep it higher than the shock so it won't lose fluid or ingest air.


Dump out the old hydraulic fluid from the pump.


Separate the two halves. You can see the piston in the reservoir. The silver pin is the working part of a potentiometer the computer uses to determine where the piston is...hence the '0' to '25' readout.


You can push the piston out with a screwdriver. I cleaned the reservoir.


Reassemble everything, but here's the trick. Leave about 1/8" between the housings and push the piston all the way down until it stops (you will see the piston in the gap). This adds a little extra volume to the reservoir. What you end up doing is slightly overfilling the reservoir and very slightly pre-pressurizing it. Use 5W shock oil and fill it to the top through the hole where the hydraulic line connects. It only takes 20-30 ml. Reconnect the hydraulic line THEN tighten down the two halves of the pump assembly.

Reinstall everything. Now your pump should actually be working from '0' all the way to '25'.



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