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Calling all Shimstackers. We need shim changes for our 06 YZ250 for Hare Scrambles.

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We have a new (off the showroom floor) 2006 Yamaha YZ250 (2-cycle) that needs some simple tuning to the suspension for Hare Scrambles.

Now I know that there is no simple solution to suspension tuning, I am looking for a simple chart or reference to get the stock shim settings and what would generally be needed for decreased high speed damping and a bit less low speed damping for Hare Scrambles.

My son ran (2-years ago) C-class and took second in district.

Last year he ran B-class and took first.

He is now running A-class and generally takes first in class and 3 or 4 overall.

He is pretty fast and is experiencing too stiff of a suspension when racing where his 2002 Honda CR250R (that has been revalved by Pro-Action) is almost picture perfect for him. I am trying to explain his general race speeds here folks, not bragging, as we know there is always someone else out there faster on any given day.

I can say that the Pro-Action revalve required us to revalve twice (each time softer) for both high and low speed until we felt quit comfortable.

Where we really need a more plush suspension is in the woods portion when especially in corners navigating roots and square edges (high speed damping too much). We need to lessen the high speed damping and we can do the work ourselves.

I am a bit mistified as to why Yamaha would not at least offer spring rates, riding conditions, rider ability, and shim valving specs for general application.

We can work with suspension tuners, but racing on the weekend does not afford us much tunaround time before the next race when the tuners are generally 75 miles or more away from our household.

Any web references you can think that would help?

Help!

Signed Shimmey.

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I would post that in the suspension forum but you might have a hard time getting somebody to give up their secret stacks.

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I thought that I'd try the posting area specific to the Yamaha YZ 2 stroke area. This bike had changed its suspension from a KYB position sensitive to a KYB speed sensitive configuration from 2006 to present. My concern was I'd get general or generic responses that did not take into consideration the newer speed sensitive system. I will let the post bake hear a couple of more days and if nothing happens, I'll try the general suspension area.

Thanks for your input.

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I know this isn't what your looking for but for 06 Dirt Riders best suspension settings for offroad were FORKS: 14 out comp. 6 out reb. SHOCK Sag 100 HS comp 1.25 comp 14 reb. 10. Also how much does he weigh? Meaning are the stock springs correct for his weight. I also have an 06 and these setting worked well for me, hare scramble, enduro, general off-road from woods to desert.

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My son is 6'-2" 180 lbs with all his riding gear (including water pack).

The square edged stuff is a big issue for him. He experiences deflecting (bars get pushed back up and wheel leaves ground in square edged corners and obsticles). I have experienced the same thing and the deflection makes our wrists hurt (stinger)... something that could lead to future wrist issues\inflamation\cronic pain\etc...

The deflection is quite scaring coming into a corner at speed ans all of the sudden the front end is off the ground and the front plows straight.

We had the same issue prio to getting out 2002 Honda Cr250R suspension revalved by Pro-Action.

There is no issue with worn parts, sticktion, missalignment with the suspension and all components are torqued to specification.

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change 17x32x0.1 to 8x32x0.1 then add a 18x0.1, stack remains same from 30x0.1 to 16x0.1 then add 15x0.1, 14x0.1 and change the 2x14x0.25 to 2x12x0.25. Try this on comp stack with 330cc oil. if you need to go softer remove 1 of the 20x0.1 shims from mid valve, leaving 2x20x0.1, 18x0.1 etc if you need more info pm me. Clicker settings 12comp, 9reb

Hope this helps.

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