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Fox Float R Evol users need some input

CO 2.0

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Just wanted to know what you guys using Fox Float R Evol front shocks are setting your pressures at on the evol and main chamber on your M8?
 
I would like to know as well? and did you find them really tight to slip on through the eyelet at the top on to the bolt?
 
Yeah wtf. I couldn't slip them on for the life of me. Lubed them up, added heat and everything. The eyelets are ever so slightly smaller than the stock spacers. Since I didn't want to force them on and have them get stuck on there, I took the dremel and sanded down the inside of the 2 top back eyelets that rest on the shoulder of the bolt. Kinda messed up that I had to do that imo...
 
Yeah wtf. I couldn't slip them on for the life of me. Lubed them up, added heat and everything. The eyelets are ever so slightly smaller than the stock spacers. Since I didn't want to force them on and have them get stuck on there, I took the dremel and sanded down the inside of the 2 top back eyelets that rest on the shoulder of the bolt. Kinda messed up that I had to do that imo...


Used the dremel as well. They are definetely on there now and they will not come off if someone tries to swipe them. My buddy who has bought a set as well has a call into fox but it looks like the OD of the bolt is a little larger on the newer sleds than Fox thinks it is?????? Brutal you pay that much for something and it is not correct WTF.:face-icon-small-dis
They do look awesome though

DSC_0333s.jpg
 
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the part number for the carriage bolt the top of the shock mounts on has not changed since 2002. We have a 2006 M7 in the shop for shock service so I measured the shoulder on the carriage bolt. It is slightly smalller than the 2011 M8 we are trying to put a set of Evol Rs on. The sleeves in the stock zero pros or standard floats can accomodate the differences in the OD of this carriage bolt but the ID on the reducer sleeves in the Evol Rs is to tight and will not allow for this apparent variance in production tolerances.
 
I'm using the X-evols and am running 30#in both chambers and the rebound at 6 and compression at 8 and high speed at 2turns
 
I'm using the X-evols and am running 30#in both chambers and the rebound at 6 and compression at 8 and high speed at 2turns

You are only running 30psi in the evol chamber? Seems really low? From the factory new, mine were set at 140psi in the evol chamber and 55psi in the main chamber with the rebound set at 11 clicks back from full clockwise tight. Seems pretty good just jumping around on it in the garage but that won't tell me much.

What ride height are you guys at? From fully extended to when I get on and jump around on the machine, my ride height drops about 1.125".
 
30 Psi is way too low, this will make the sled into a stink bug. You are going to want to start around 65 in the main and 180 in the Evol, make small adjustments from there. Remeber to lift the skis of the ground when making adjustments!
 
You are only running 30psi in the evol chamber? Seems really low? From the factory new, mine were set at 140psi in the evol chamber and 55psi in the main chamber with the rebound set at 11 clicks back from full clockwise tight. Seems pretty good just jumping around on it in the garage but that won't tell me much.

What ride height are you guys at? From fully extended to when I get on and jump around on the machine, my ride height drops about 1.125".


Mine came the same way from the factory. ride height drops roughly the same as well.
 
Is everyone running these with the reservoir on the bottom, is it possible to run them with it on top?

I was wondering the same thing considering the stock floats are opposite orientation. Instructions say the evol chamber needs to be mounted on the bottom on all applications.

Klimbing, let me know what you end up with for settings once the snow falls.
 
30 Psi is way too low, this will make the sled into a stink bug. You are going to want to start around 65 in the main and 180 in the Evol, make small adjustments from there. Remeber to lift the skis of the ground when making adjustments!

at those pressures my front end was front end would not move on 20ft drops, and mine are X 's not r's and the combined pressures are 60psi which is what i run in a std float!!!! and at 30+30 the front end feel the same as it did with the std float and the same height
 
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On Evol type shocks (including Evol X), you typically want the Evol chamber to be higher then main chamber air pressure. Remember the Evol chambers primary job is to help control bottom out. The main chamber air pressure controls ride height, and 60-80% of normal riding.
For most riders a main chamber air pressure in the the 45- 65 psi is the norm and 85-125 for the Evol.
Some of your top pro snocross racers usually do not use more then 170 in the Evol chamber on 100 foot gap jumps.
Rebound adjustment can also have a minor effect on compression dampening.
On our website we have a down loadable air spring pressure chart for basic recommendations. That is www.tomssnowmobile.com It is under Fox focus located at the top, scroll down to "Fox Shox tech center".

The reason you are having trouble installing the new R shocks on the Arctic Cat, is mostly due to production tolerances on the diameter of the bolt from OEM. It appears Cat may be migrating toward a larger diameter bolt to help standardize that bolt. Fox can address that issue as soon as Cat determines the final bolt size. Until then you may need to slightly modify your sleeves to fit the bolt. Test fitting the sleeve before trying to install the shock will save some time. The best bet would be to drill the sleeve if it needed to be enlarged.

Tom
 
On Evol type shocks (including Evol X), you typically want the Evol chamber to be higher then main chamber air pressure. Remember the Evol chambers primary job is to help control bottom out. The main chamber air pressure controls ride height, and 60-80% of normal riding.
For most riders a main chamber air pressure in the the 45- 65 psi is the norm and 85-125 for the Evol.
Some of your top pro snocross racers usually do not use more then 170 in the Evol chamber on 100 foot gap jumps.
Rebound adjustment can also have a minor effect on compression dampening.
On our website we have a down loadable air spring pressure chart for basic recommendations. That is www.tomssnowmobile.com It is under Fox focus located at the top, scroll down to "Fox Shox tech center".

The reason you are having trouble installing the new R shocks on the Arctic Cat, is mostly due to production tolerances on the diameter of the bolt from OEM. It appears Cat may be migrating toward a larger diameter bolt to help standardize that bolt. Fox can address that issue as soon as Cat determines the final bolt size. Until then you may need to slightly modify your sleeves to fit the bolt. Test fitting the sleeve before trying to install the shock will save some time. The best bet would be to drill the sleeve if it needed to be enlarged.

Tom


Cheers Tom

Thanx for the great info

KK
 
Great info Tom, thanks.

I originally tried to drill out the aluminum eyelet with one size bigger drill bit but it kept catching. Not to mention the force I had to apply to it with a vise to hold it in place. Even with a towel it still slightly damaged the eyelet (nothing major though). Sanding with the dremel was much easier and took less vise pressure to keep the eyelet in place. So no damage was done to the eyelet.

Klimbing, are you gonna keep that orientation of the mounting? It both has its bads. First is that with the shock body low it will get knicked more easily from low lying debris. With the orientation the way Fox recommends is that the evol chamber sits low and gets hit by debris. Hmm, not sure which orientation would be the most "safe" for the shock... With the evol chamber down it definitely sticks out further away from the ski and lower A-arm making it more of a rock magnet. I swapped my orientation with the evol chamber up. It definitely looks better. A Boondockers employee told me he has his evol chamber up for the same clearance reasons I mentioned.
 
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Great info Tom, thanks.



Klimbing, are you gonna keep that orientation of the mounting? It has its good and bads. Good is that the shock body isn't low so it won't get knicked as easily from low lying debris. Bad is that the evol chamber sits low and gets hit by debris. Hmm, not sure which orientation would be the most "safe" for the shock...


They are going to stay where they are for now....... as I don't think I can get them off without damaging something. They are on really really tight
 
Got to change sides left to right and the chamber will fit with the top orientation. If you just flip them over while on the same side as before they will hit the A-arm.
 
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