Author Topic: Mountain Bike Tires  (Read 446 times)

Svend

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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 »

jim-ratliff

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Re: Mountain Bike Tires
« Reply #16 on: May 11, 2012, 07:37:10 pm »
Thanks Svend. That does make sense. Yes, since the middle of last year it feels like they are working well.  I read somewhere that rebound should be as slow as possible as long as you aren't hitting bumps so frequently aht you wind up compressing the front shock.  Since I subsribe to LivingProof's theory of moderation in all things, we are probably at about 8 clicks out of 11 towards the soft end. And same on the rear shock.


Our biggest learning curve was pulling up on the handlebars to climb - and that coupled with shocks that were rebounding too quickly back then made pulling the front wheel off the ground way too easy.  I've ridden some of those same trails since then and they are actually pretty easy (with the weight forward, the shocks slower, and hands softer, and pedaling less hard in the low gears). I guess that was another difference, the torque that we could generate in the lower gears is day and night from low gears on a road bike.
"If you're gonna play the game boy, ya gotta learn to play it right."

Svend

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Re: Mountain Bike Tires
« Reply #17 on: May 11, 2012, 08:00:11 pm »
I keep forgetting that you're coming from years of road riding.  Must be tough to unlearn all those habits and techniques in the transition to singletrack.  I have never done any road cycling, except as a kid through the neighbourhood on my old 10 speed.  All of my riding in the past 30 years has been on a mountain bike.  What I am "learning" now, is not actually new, but just the relearning of stuff that I already knew years ago, before taking a 15 year break from the sport (read:  kids, house, small business to run....).

In that context, riding on the new bikes is a piece of cake -- lighter weight, suspension, better geometry, better tires, shifters, the works.  All of the skills that Terryl and I learned 30 years ago were on rigid, steel frame bikes.  Tire selection was minimal -- Specialized Ground Control and Panaracer Smoke and Dart...that's about it.  The bike's suspension was our knees and elbows.  But we still ripped up the trails, and got pretty darn good at it, too.  We rode just about any trail we could find, except the rockiest and gnarliest.  But shallow river crossings, steep descents, deep mud were candy to us.

Ah, but what a fun sport it is.  We love it.  Next best thing to skiing, in my books.  Great to hear that you and Lynn are enjoying it so much.  Keep smiling!

« Last Edit: May 11, 2012, 08:45:15 pm by Svend »

bushwacka

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Re: Mountain Bike Tires
« Reply #18 on: May 11, 2012, 08:54:54 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?

doesnt do anything except set sag. Also keep in mind every person is different and most shocks valving is not correct for most people. For true nirvanna PUSH industries can do some really good things for shock tuning.