Adding oil to rear suspension preload adjuster

Over the years the preload adjustment of the rear spring tends to "get tired". Turning the adjustement wheel tighter does not lift the bike as it used to. The preload adjustment in the stock Showa rear spring is done by hydraulic oil (jack oil) and eventually some of it (if not all) just disappears. In the following I show how to refill it.

A word of warning: I have heard of at least two preload adjusters that have been broken (the threads have been shot) because the adjuster has been turned with the bike loaded or even just sitting normally on ground.  So I advise that you only adjust the preload with the bike on centerstand in order to prevent extra stress to the adjuster wheel.

Put the bike on center stand and turn the adjuster all the way open (counterclockwise). Then release the bolts of the adjuster so that you can hold it in your hand.

When you have the adjuster in your hand, grab it firmly with a vise grip or similar and open the hose connector. Do not loose the copper washers! 

When the hose is disconnected, store it temporarily in uphill position so that it will not accidentally drain out.

Like this....

Make sure the adjustment wheel is turned all the way open (counterclockwise). Then place it on the floor and after this use a thin screwdriver or similar to push the piston all the way down. 

Next use a pipette to fill the chamber above the piston with jack oil. Fill it all the way.

When you have filled the adjuster, reconnect the hose to the adjuster. Remember the copper washers. Try to tighten the connector in the same position as it was so the hose comes out in correct position.

When the adjuster is in place, turning it clockwise (tighter) should the rear spring get slightly longer and thus it should feel a little stiffer as well. However, if the rear spring has already lots of miles behind, this trick will not bring it to back to "as new" condition. This is just a simple "first aid" to those who feel that their bike seems to sit lower than what it used to.

A more permanent fix to improve the LT's suspension is to change both front and rear springs to Öhlins or Wilbers or similar. I went for Öhlins and the bike certainly feels more stable especially in long sweepers