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Existentialism-- Just a bloody good excuse to go riding...

Friday, April 30, 2010


Just found another article where a much better maintenance guide and info on the KS post was done

Did this sometime back...

This is my second adjustable seatpost. Had the reported issue like many with the scratched stanchion. It was sent back to the manufacturer in Taiwan and came back with a new stanchion. But things didn't last long before the scratches started appearing again.

This time I notice that the marks became worse as the post gets drier. It was said to be due to the master bushing (roller bearing according to the manual). Definitely the roller bearings are hitting on the stanchions but not having lubrication sure aggravated the problem. Lastly I guess it also depends a lot on the seat tube angle. The slacker and the more pointed upward the seat is, probably the greater the issue as with all kinds of adjustable seat posts.

The other problem that started appearing as the lubrication disappeared from the stanchion after some usage time after a rebuild/relubing of internals was a slight lateral play. Nothing major and certainly not like the kind of slop found on Joplins.

Better to strip everything down and check again.

Simple enough with a socket wrench and circlip plier and following the in structions on the booklet. While I already noted that the outside of the stanchion was dry and causes some sticking when trying to move the post, first thing noted after stripping was the lack of any oil left inside the stanchion and that is probably part of  the cause of the stickiness as well.

I substituted the recommended 20-30 weight oil with some lubrication for 2-stroke engines.. dunno what they are actually called. Just jet 25ml and took a gamble it wouldn't screw up the o-ring seals (so far all seems ok after a couple of months).

Examined the scratches and determine that apart from being fugly, no harm done. Any prolong dry scratching might eventually crack of pieces of the anodizing around the scratches but with periodic lubing of the roller bearing from the inside should make this post last for awhile.
Put everything back in reverse order. Remember to tighten down the retaining nut at the bottom properly with a socket wrench and ensure the red anodized ring on top is not too loose. Otherwise both will lead to the seatpost being able to be pulled up even if lever is not depressed.

Scratch or not, thing is smooth as silk.

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