Re-springing a 2017 Alta Redshift MX (and then revalving too)


Silent But Dirty

Alta North
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Canada
How did you diagnose that?
I didn't, my suspension company did.

They say it's common to see poor qc of the anodizing thickness inside the cannister, which can lead to nitrogen bypassing the piston band. My bike is only at 20hrs and the tech said the nitrogen was already 50psi low, as well as showing signs of contamination in the oil.
 

Fod

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CA
I didn't, my suspension company did.

They say it's common to see poor qc of the anodizing thickness inside the cannister, which can lead to nitrogen bypassing the piston band. My bike is only at 20hrs and the tech said the nitrogen was already 50psi low, as well as showing signs of contamination in the oil.
Yeah leaking to atmosphere the ifp pressure is different then bypassing the piston and causing cavitation of the oil. If you like the piston design over a bladder, I recommend the tank if you end up changing it out. Either way look out for other designs that are longer and may interfere with subframe.
 

Silent But Dirty

Alta North
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Canada
Yeah leaking to atmosphere the ifp pressure is different then bypassing the piston and causing cavitation of the oil. If you like the piston design over a bladder, I recommend the tank if you end up changing it out. Either way look out for other designs that are longer and may interfere with subframe.
Thanks for the heads up.
 

Duncan

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Newport, RI
Philip, Thanks for sending the factory developed MX suspension specs.

Out of curiosity I compared the shim stacks in my EX with your chart and summarize as follows:

Base valve shims - mine are exactly same as your MX Alta says.

(why do you not list the four 6 X 28 X .15 shims in your actually on MX, were they really not installed?)

Mid-Comp - I did not dismantle.

Rebound - mine are dramatically different from MX Alta says and actually on MX and Alta MX team.
 

Philip

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(why do you not list the four 6 X 28 X .15 shims in your actually on MX, were they really not installed?)
Good catch! I must have forgotten to list them after I found them. I only bought eight extra 6 X 28 X .15 shims for both legs, whereas the specs call for 16 shims total.
 

Silent But Dirty

Alta North
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Canada
I've finally gotten my 2017 MX back from being valved to the specs Phillip obtained from Alta.

This has completely changed the behavior of the bike for the better. Clearing jumps is so much easier, and I now have the confidence to hammer through whoops!

I have gotten my fork compression dampening out 22 clicks, and it's still at bit harsh, so I am going to try lowing the oil height a bit and see if I like that better.

There was one issue on the shock, where the anodizing in the resivoir is of poor quality, which allowed nitrogen to bypass the piston and mixinto the oil.

Putting a bladder kit in was not an option, as it seems this resivoir was made special for the Alta in order to clear the subframe. New resivoir had to come all the way from Austria.
 

Don Thuren

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Bend, Oregon
Awesome thread I think I'm going to go through tuning my 2017 MX myself. Been wanting to dabble in moto suspension more anyways so good excuse to do it!
 

Don Thuren

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Bend, Oregon
Philip I see in your specs you used the Race Tech compression base, which I was planning on using too.

Did you try the Race Tech low-speed control kit at all, or thoughts on that?
 

Philip

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Philip I see in your specs you used the Race Tech compression base, which I was planning on using too.

Did you try the Race Tech low-speed control kit at all, or thoughts on that?
Yes, I did use the RaceTech base valves. You also have to flip the white/right leg compression needle valve upside down so that you have two rebound clickers at the top and two RT compression clickers at the bottom.

I am not familiar with the RT low-speed control kit, sorry.
 

Don Thuren

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Bend, Oregon
Sweeeeeet yeah saw that with the check needles totally makes sense. I may do the LS bleed kit too, as I hate suspension that is TOO mushy....
 

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