Author Topic: Mountain Bike Tires  (Read 448 times)


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Re: Mountain Bike Tires
« Reply #15 on: May 11, 2012, 06:33:22 pm »
Yep, Jim has.

But I do have a question. There was a rubber O-ring around the rear shock. That is what you used to see how much the shock was sagging (getting compressed). The guideline was that static compression just from body weight was about 25% of the travel.  That rubber ring is gone from Lynn's bike.  Do I need to get it replaced?  Does it serve any other function, such as cleaning the piston before the dir would get dragged into the seals?

Kinda figured you'd played with the settings.  Sorry for questioning a perhaps obvious thing.  Have you found some good settings yet that are working for you?

As for the rubber ring, I don't think that it serves any cleaning function, as the business end of the piston (that which sees all the travel) is going to get dirt on it no matter what.  The ring will never be in that zone -- as soon as you start pedaling it will move further and further away from the shock seals.  But it is useful for checking sag, as you say.  You can check sag two ways:  using this ring and the length of it's deflection from unweighted to weighted; or by measuring the entire length of the shock when weighted and unweighted, and comparing the two values.  The latter, however, requires a second person to wield the tape whilst you sit astride the bike.  Whereas the ring allows you to do this solo.  Quick and easy replacement for the ring:  a medium size zip tie, snugged up tight to the piston, free end trimmed.  Works on front forks too.
« Last Edit: May 11, 2012, 06:40:19 pm by Svend »