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Discussion Starter · #1 ·
Hello all. First post...and yes I searched but could not find a relevant answer even though this is a highly discussed topic, I know.

When addressing stiction on a front fork (and I assume make/model notwithstanding unless I am missing this as well??), is that initial breakaway force needed to start the fork travel created from the dust wiper seal sticking to the stanchions or the air spring and/or damper piston sticking to the legs....or am I still off? If it matters, I am talking about a 2019 RS Revelation RC.

Thanks in advance for some good insight :thumbsup:
 

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Depends what is the worst fit.

Bushings can be the worst (if they are tight) and air seals usually second worst (i.e. X-fusion twin quad-ring air piston) with dust wipers a bit below (unless they're very tight).

But if everything is good and seals all lubricated and sized correctly you're good.
 

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Discussion Starter · #4 ·
Air spring seals primarily, whether fork or shock. The lack of them is a major contributor to the supple feel of coil-sprung suspension.
So is it a logical assumption that even a top shelf air sprung fork will suffer from the same thing then? Or is there a price point on an air sprung fork where that super supple feel is comparable to a coil sprung fork? Just seems odd to me that this is even a problem in this day and age of technology yet there's not shortage of complaints it seems.
 

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Discussion Starter · #5 ·
Depends what is the worst fit.

Bushings can be the worst (if they are tight) and air seals usually second worst (i.e. X-fusion twin quad-ring air piston) with dust wipers a bit below (unless they're very tight).

But if everything is good and seals all lubricated and sized correctly you're good.
Yeah I get that at least with the bushings since this fork is literally brand new. Might just need to be ridden to clearance themselves. But I've also read where you need to service the lower legs....even on an out-of-the box new fork. What kinda nonsense is that??
 

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Everything has a tight fit from new so it can "break in" to a reasonable level of friction. Making a perfectly friction-less fork from the first bounce would either take a huge extra manufacturing cost or become loose/leak very quickly.

Seals sitting for a while will also "grab" as well as the oil will drain out of the foam rings

This is just a fact of producing a product that is relatively light that takes a huge beating. Forks are getting better but you can always go just that tiny better no mater how good it is...
 

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Yeah I get that at least with the bushings since this fork is literally brand new. Might just need to be ridden to clearance themselves. But I've also read where you need to service the lower legs....even on an out-of-the box new fork. What kinda nonsense is that??
I generally have a couple rides then drop the lowers. With the small amount of oil that lubricates the lowers it has always been a good idea after break in to do such even if the level was spot on.
 

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You have a RC damper. The harshness you feel isnt from seal stiction, its the damper.

You'll never get a seal to be SO smooth that it erases a 4 inch tall square rock. Tiny pebble chatter, maybe, but thats not the hand smashing soreness you get from a normal trail ride. Thats all the damper beating you up.

I've had a lot of crazy butter smooth coil moco forks, and they're still jackhammers. Sure, the tiny tiny bump compliance is very smooth, but thats not all that important unless you're just riding smooth gravel trails.

Old dual air forks could be setup to be basically frictionless, but same thing. It didnt really matter since the damper couldnt hold up.

The exemption is binding bushings. Thats not very common, but it'll cause nuts stiction.

You need to retune or replace the RC damper.
 

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Yeah I get that at least with the bushings since this fork is literally brand new. Might just need to be ridden to clearance themselves. But I've also read where you need to service the lower legs....even on an out-of-the box new fork. What kinda nonsense is that??
Greasing the top bushings and seals will make the fork slide far better initially. Otherwise you've got to wait for oil to work it's way up.
 

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Hello all. First post...and yes I searched but could not find a relevant answer even though this is a highly discussed topic, I know.

When addressing stiction on a front fork (and I assume make/model notwithstanding unless I am missing this as well??), is that initial breakaway force needed to start the fork travel created from the dust wiper seal sticking to the stanchions or the air spring and/or damper piston sticking to the legs....or am I still off? If it matters, I am talking about a 2019 RS Revelation RC.

Thanks in advance for some good insight :thumbsup:
Based on your post, I will assume you are experiencing stiction issues with your Revelation. If so, hopefully this will help:

My wife has a new 2019 Revelation RC on her Fuel EX and the fork had stiction issues during initial travel. I'm sure her light weight made the issue worse. I dropped the lowers and the fork looked to be low on oil and grease. New oil and Slick Honey reduced the stiction a lot, but things could have been better. Next, I replaced the RS seals with a low friction kit from Push. Problem solved! The fork is buttery smooth now.
 

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Otherwise you've got to wait for oil to work it's way up.
What about that trick I saw in a video where you invert the bike for 15 seconds, then flip it upright and pump it a few times? Gets the oil down to the top and then you wipe it around when you pump it, I guess.

I never remember to do this but it seemed like a cool trick when I watched it a little while ago.
 

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What about that trick I saw in a video where you invert the bike for 15 seconds, then flip it upright and pump it a few times? Gets the oil down to the top and then you wipe it around when you pump it, I guess.

I never remember to do this but it seemed like a cool trick when I watched it a little while ago.
Does nothing unless it's a new fork that has been assembled dry. In which case it's more like 15 hours.

If a fork is working properly the lube gets up there anyway. If the fork isn't then inverting it for 15 seconds isn't going to help.
 

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Discussion Starter · #13 ·
You have a RC damper. The harshness you feel isnt from seal stiction, its the damper.

I've had a lot of crazy butter smooth coil moco forks, and they're still jackhammers. Sure, the tiny tiny bump compliance is very smooth, but thats not all that important unless you're just riding smooth gravel trails.

You need to retune or replace the RC damper.
I'm confused. What do you mean RC damper? This fork has the Motion Control damper.
 

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Discussion Starter · #14 ·
Based on your post, I will assume you are experiencing stiction issues with your Revelation. If so, hopefully this will help:

My wife has a new 2019 Revelation RC on her Fuel EX and the fork had stiction issues during initial travel. I'm sure her light weight made the issue worse. I dropped the lowers and the fork looked to be low on oil and grease. New oil and Slick Honey reduced the stiction a lot, but things could have been better. Next, I replaced the RS seals with a low friction kit from Push. Problem solved! The fork is buttery smooth now.
This was the next thing I was contemplating...after I get 15 or so hours on it, service the lowers and add the Push dust wipers and foam rings. So it made that much of a diff huh? I was going to ask if low friction dust wipers from Push or Racing Brothers actually worked or is it snake oi... for you, sounds like it actually worked. If this is the case, then it answers my initial question as to what is causing this stiction in the first place. At least it was for you anyway.
 

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Air volume, more than 10ml will make it hydraulic on the spring side. DVO uses a cartridge for the Air assembly so it can take more.

Also using more in the damper leg means more that can be sucked in to the damper over time so if you were to add more you will need to rebuild the damper more often!
 

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What's the hold up on just putting more oil in the fork leg? Volume?

Like that the DVO takes like 20/30ml vs the 5ml my pike called for.
As far as I know:

1) The air in the lowers acts as a spring too. The spring side on an air fork, like the Pike, has its stanchion bottom completely sealed, leaving really low amount of volume, hence 5mL on that side and a bit more on damper side.

2) Risk of damper blowing up. It gets overfilled from oil ingress, if you do not follow service intervals as recommended. Oil migrates into the damper at the lower sealhead, in small amounts over time as oil film makes it past the sealhead. That and they also don't want to over-do the sealhead's sealing ability due to stiction (also weight, cost, etc.). Engineering challenge to create a seal that keeps oil in (and pressure), and also keep oil out, on a sliding shaft that's porous.
 

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My new yari was crazy sticky. I could lean on it and it would just jump 5mm of travel at a time in steps. I tore it down and opened the air spring. There was no grease on the bottom side of the air piston bushing. After Just putting sram butter here i could sense the difference in friction just sliding the shaft freely up and down when not installed in the fork. Next i worked a bunch of butter into the piston seal itself.

For the lowers, after i put the foam rings in, it looked like the area could hold more oil. So i used a syringe to fully soak the foam areas with oil after installation. Then popped the lowers back on.

These things made a noticeable difference and didnt cost me anything but time. Stock fork seals etc.

now that i have a bunch of rides on it, things have loosened up and it feels okay to me.

of course removing that seal friction completely (coil) is very noticeable on very small movements when at sag. So i guess there is a bit more floating on air sensation. (Paradox. :) )

Tip: when i get ready for a ride, i set the bike upside down against my tailgate. Rear tire on the ground. Handlebars on tailgate end. I check tire pressures etc. get gear ready etc. while this is brief. It does give the oil in the lowers a little bit of time to travel upwards into the bushing areas. the five minutes or so makes me feel like its better than none. Especially after the bike sits vertical unused for a week and i know that 5-10ml of oil is doing nothing but sitting pooled at the bottom.
 

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So, I'm running a Yari for the second season. After a lowers service last winter, the fork was noticeably more supple than new, likely due to break in and wear (and fresh lube). I just had a Charger damper and Debonair upgrade kit installed a couple of days ago, and the fork is now super plush. Better parts with seals chosen for lower static friction do make a significant difference in ride quality.

Sent from my Pixel 2 using Tapatalk
 

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I'm confused. What do you mean RC damper? This fork has the Motion Control damper.
Sorry for the mixup, RS does offer a revelation charger RC, but they did have a moco one too that I forgot about. The comment applies doubly the moco RC!

Dont get me wrong, definitely cover your bases regarding seals sticking and lower leg lube being adequate... but that damper chokes and spikes majorly. A charger upgrade, or an aftermarket damper upgrade would transform the fork overall.
 
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