Betor shock seals

[David Lahey]

Using additional air pressure can also increase stiction. I was another one who frigged around endlessly with air pressure in the forks of my TY175 in the 1970s. Yes the adjustability was a bonus, but anything more than a couple of psi made the forks work poorly in small rocks, which I attributed to the stiction/friction between the seal lips and the fork tubes.
Some bikes like my 1976 Cota 348, and my 1978 RM250C, have low rate coil springs and air pressure combined, and are hell to keep at the setting you want due to the temperature of the air inside changing as you rode. The Cota now has Bultaco Sherpa T springs and the forks work great.

[Takhli44]

Guess I'm with Pop on this one, Haven't noticed any stiction (have seals that are supposed to reduce it) with 12 PSI. Found it stuck a little when my homemade fork brace didn't fit perfect. Had to fool with it quite a bit. Then again perhaps my riding ability (inability) don't allow me to tell the diffrence. I'll watch for a change in the future. Maybe I can shave a couple of points?

Anyone try a stack of washers and/or more or less oil in RL250 forks?

[pop]

I thought stiction didnt really surface untill the fork diameter was around 44mm and/or was coated with the special coating that the forks have these days, and air did cure some chronic seal leaking problems, especially the special seals that had the lips on the outside edge aswell, which didnt work without some pressure.

[pop]

Oh yes Takhli, I used to pile 10c and 20c coins into everything[dimes and quaters in your language] not really worth the money as the coils might start binding .

[FM350]

If you have air assisted forks on a TS bike, then fitting the proper rate springs and using the air caps to bleed air out rather than to add pressure, will improve fork action noticeably. Action of air assisted forks is generally harsher due to increased seal stiction, and as air volume is very low, heat will affect the pressure and feel/action will vary.