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Workshop => Suspension and Chassis => Topic started by: andy@maultechatv on January 16, 2014, 12:49:34 PM

Title: Fox Evol Air Chambers Explained
Post by: andy@maultechatv on January 16, 2014, 12:49:34 PM
Here's another video. Enjoy

[video=youtube_share;uTbUj7w3PJA]http://youtu.be/uTbUj7w3PJA[/video]
Title: Fox Evol Air Chambers Explained
Post by: andy@maultechatv on January 16, 2014, 12:52:12 PM
Another

[video=youtube_share;eS_vnAFjf7w]http://youtu.be/eS_vnAFjf7w[/video]
Title: Fox Evol Air Chambers Explained
Post by: rablack21 on January 16, 2014, 01:20:53 PM
Andy, what is your personal take on these air shocks versus the coiled shocks? Which one do you think it easier to tune? Do you think it is worth the money to swap to the air shocks?
Title: Fox Evol Air Chambers Explained
Post by: JoePA on January 16, 2014, 02:32:03 PM
I think i heard him say he liked the standard spring shock over the fox. It's easy to see whats going on and where the crossover comes into plar with the clear sleeves he installed and I trully think it would be MUCH easier to tune the shocks if you could see the piston(s). This is where, i think, It's easier to use a standard spring plus it, once again I think, more consistant over the air setup.

Don't get me wrong I wrode a CRF450 with Fox shocks and WOW it was amazing and much better than my axis but after talking to Andy, my shocks aren't set up right...that will be fixed shortly!
Title: Fox Evol Air Chambers Explained
Post by: Pricecheck on January 16, 2014, 02:35:51 PM
Here's a good question since I run the evol floats. When will fox make an air shock for the rear that is equivalent to the evol's?  It's not a huge issue right now but I'm building a hybrid for my wife and I want the floats since they are easier to adjust and all I have to do is raise or lower pressure for the difference in weight. Being that pretty much all rears are coiled, this leaves me having to choose a shock stiff for her and soft for me in order to work.

Anything in the r&d department that you may have heard of?
Title: Fox Evol Air Chambers Explained
Post by: andy@maultechatv on January 16, 2014, 02:58:43 PM
I like the spring shocks better just for the fact that I can diagnose a problem easier over the phone with them.  Air shocks will dive more too.  

If you are going with an air shock just for less weight I would get an aluminum body spring shock with a titanium spring.  I bet you would be surprised how close they are.

As for a rear air shock I would doubt it for a while.  Did you see Ryan Dungey ran one last year on his supercross bike and it broke before he left the line?

If you think that air shocks are infinitely adjustable externally then you're wrong.  The problem with these is that one shock doesn't meet everyone's needs like they try to make you think.  The more air pressure you run the heavier the valving needs to be internally!  Yes you can get by but that doesn't mean it's right.
Title: Fox Evol Air Chambers Explained
Post by: hontrx265r on January 16, 2014, 05:34:51 PM
I think I like the fox less after watching this video. It looks to always be a compromise on one end or the other. When your trying to dial in ride height, or bottom out pressure your always loosing on one end. I would assume the valving comes into play here as the most important component. However with a coil shock you can keep your spring pressure your valving and change your crossover without the bleed over effect. I've also built the Axis pro airs and they have the adjustable crossover  but the evol chamber on a fox allows the pressure to build faster and greater due to the volume of the chamber. You should do this same thing with the Pro airs to simulate the difference. Your videos are awesome, not one person on here who can't appreciate them. Thank you.
Title: Fox Evol Air Chambers Explained
Post by: andy@maultechatv on January 17, 2014, 07:12:14 AM
The difference with the Axis Pro Airs is that they actually have a crossover. But the Axis crossover is backwards from a spring shock (the more you remove the quicker it crosses over).  I'm glad you see that how the fox evols are NOT as infinitely adjustable as most think and the valving is very important with them.
Title: Fox Evol Air Chambers Explained
Post by: D Bergstrom on January 18, 2014, 01:23:50 PM
Great videos, thanks for taking the time to make them. So you didn't mention it in the video, but I am guessing you have revalved the Evol's to make them work better? What air shock do you think is better and has more potential, Evol's or Pro Airs?

Quote from: andy@maultechatv;22534
I'm glad you see that how the fox evols are NOT as infinitely adjustable as most think and the valving is very important with them.

I have owned two sets of Evols on one of my 450R's, and I always felt the valving was "generic". They were good shocks, but I never was truely happy with them, feel it was all in the valving. I spent ALOT of testing time on them. Wanted to send them off and get some valving work done to them, but just ended up selling them and going back to a standard coil shock. Thinking about going to air shocks on the front of my 250R, but if I went Evol's I would for sure like them revalved. Have aslo thought about the Pro Airs, but haven't really heard much about them. Are the Pro Airs custom vavled, or do they have "one size fits all" valving like the Evol's?

Doug
Title: Fox Evol Air Chambers Explained
Post by: andy@maultechatv on January 18, 2014, 05:05:32 PM
Yes the valving will need changed on the evol. The axis pro air will be specifically valves for your application and weight. Also customer service at axis is way better.
Title: Fox Evol Air Chambers Explained
Post by: andy@maultechatv on January 18, 2014, 05:08:16 PM
To valve a set of evols we will need to know how much body is showing while on the bike and the air pressure your running in the main chamber