So i have two coil 40s and one air
I cant ride for a while so i decided to whip my junk air fork that came on my used mondraker summum into shape. I had ridden it once or twice with the air fork and it felt like shit, so i swapped my coil on.
The air fork came with 200 volume spacers in it and was filthy inside and out. I decided I wanted to give it the best shot against the coil forks, make it a dual air.
A. Positive and negative chambers can be adjusted seperately
B. The seal wont have to slide across a notch, prolonging seal life and likely less friction.
C. Float or gold oil can be used instead of slickoleum and wont migrate to the negative
D. Air volume can be adjusted by adding moar of the aforementioned oil.
Machined a "butted stancion" that is/was for the damper side or coil forks, normally they have a short recess for the coil topout plate and a groove for a spirolock type snap ring. Had to machine the recess larger and deeper for the air sealhead and the odd air snapring. This was done to get a stancion with no internal dimple. I also checked some of the "non butted" way way old like first kashima stancions and the ID is much smaller and would not be possible to use with the air piston.
I drilled the center hole.
The piston on a 40 does not connect the negative with the piston rod. In stock configuration the footbolt vents the rod to the lower, on a 36 the inside of the rod does contribute to the negative spring and the footbolt is sealed fron the lowers. Im not sure why fox decided not to use the rod for negative volume on the 40, maybe the gigantic negative bulb on the piston is amply sufficient. But for better or worse the 10cc of rod volume is incorporated into the negative volume on my fork. Although i could add moar oil to the negative to change the volume if i felt the need. I drilled the center of the piston in the lathe and installed the mrp fulfill valve in place of the footnut can be seen in the background
For the damper I used an NBO fit RC2, the new rebound pistion, the newer sealhead, MOAR shimz, i usually add one face shimz, on this one I added two, hoping to have enough damping to run without the HSC adjuster donking up the curve.
Im recovering from a surgery so no ride report, but putting 5psi moar air in the negative than positive sure does seem to make the thing more supple makes it "more coil like"
It cost about 50$ for the fulfill valve which is pretty expensive for what it is. and a 24 pack of corona to get my friend to chuck the stancion in a big lathe (my 10" lathe doesnt have a big enough throat to allow a long part like a stancion to pass through)
This fork carrys two more secrets, on the outside
Can you spot them?
I cant ride for a while so i decided to whip my junk air fork that came on my used mondraker summum into shape. I had ridden it once or twice with the air fork and it felt like shit, so i swapped my coil on.
The air fork came with 200 volume spacers in it and was filthy inside and out. I decided I wanted to give it the best shot against the coil forks, make it a dual air.
A. Positive and negative chambers can be adjusted seperately
B. The seal wont have to slide across a notch, prolonging seal life and likely less friction.
C. Float or gold oil can be used instead of slickoleum and wont migrate to the negative
D. Air volume can be adjusted by adding moar of the aforementioned oil.
Machined a "butted stancion" that is/was for the damper side or coil forks, normally they have a short recess for the coil topout plate and a groove for a spirolock type snap ring. Had to machine the recess larger and deeper for the air sealhead and the odd air snapring. This was done to get a stancion with no internal dimple. I also checked some of the "non butted" way way old like first kashima stancions and the ID is much smaller and would not be possible to use with the air piston.
I drilled the center hole.
The piston on a 40 does not connect the negative with the piston rod. In stock configuration the footbolt vents the rod to the lower, on a 36 the inside of the rod does contribute to the negative spring and the footbolt is sealed fron the lowers. Im not sure why fox decided not to use the rod for negative volume on the 40, maybe the gigantic negative bulb on the piston is amply sufficient. But for better or worse the 10cc of rod volume is incorporated into the negative volume on my fork. Although i could add moar oil to the negative to change the volume if i felt the need. I drilled the center of the piston in the lathe and installed the mrp fulfill valve in place of the footnut can be seen in the background
For the damper I used an NBO fit RC2, the new rebound pistion, the newer sealhead, MOAR shimz, i usually add one face shimz, on this one I added two, hoping to have enough damping to run without the HSC adjuster donking up the curve.
Im recovering from a surgery so no ride report, but putting 5psi moar air in the negative than positive sure does seem to make the thing more supple makes it "more coil like"
It cost about 50$ for the fulfill valve which is pretty expensive for what it is. and a 24 pack of corona to get my friend to chuck the stancion in a big lathe (my 10" lathe doesnt have a big enough throat to allow a long part like a stancion to pass through)
This fork carrys two more secrets, on the outside
Can you spot them?
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