After a short hiatus, there's been a resurgence of coil-sprung shocks and forks hitting the market, but this time around they aren't getting installed on downhill bikes. Instead, they're showing up on everything from mid-travel trail bikes to full-blown enduro race machines. Air-sprung suspension has become incredibly evolved, but there are still plenty of riders out there who prefer the extra small-bump sensitivity that a coil-sprung setup can provide.
Push first joined in on the coil revival with the release of the eye-catching, steampunk-esque ElevenSix shock back in 2015, and last year the Colorado-based company followed up with the ACS3 conversion kit.
Push ACS3 Details• Converts air-sprung fork into coil-sprung
• Kits available for RockShox Pike, Lyrik, Yari, and Fox 36
• Air-sprung bump stop
• Seven spring weight options
• Weight: 367 grams more than stock on a 29" 150mm Lyrik
• Made in Colorado
• MSRP: $389 USD
•
www.pushindustries.com The ACS3 allows riders to convert their 2015-2018 Fox 36, 2014-2018 RockShox Pike, or a 2016-2018 Lyrik or Yari forks from air to coil. All of the components are hand assembled and manufactured in Push's facility in Loveland, Colorado, which helps explain the kit's $389 USD price.
InstallationInstallation of the ACS3 kit is a straightforward process, and if you've ever performed a lower leg service on your fork is shouldn't be too much of a hassle. Even if you've never done anything except add some air and twist a few dials on your fork, Push have created
instructional videos that goes through all of the steps in a clear, easy to understand manner.
I'd budget in an hour for the procedure from start to finish, but in reality it'll probably take much closer to 30 minutes. Basically, you're pulling off the lower legs, undoing the C-clip that holds the air spring in place, removing the air spring, and then putting in the lower portion of the ACS3 kit. The lowers are then slid back on, 20cc of oil is put into each leg, and then the foot nuts are tightened down. After that, it's just a matter of dropping in the correct spring, installing the top cap, and airing up the bump stop to the desired pressure (anywhere between 5-50 psi).
One of the downsides to a coil fork is that it's not possible to control the spring rate as precisely as you can with an air fork, where it's easy to add or remove one or two psi. That being said, Push have seven springs available, which, on a 150mm fork, means there are options for riders from 115 to 240 pounds.
It's also worth noting that once you install the ACS3 kit, it's a relatively permanent conversion. You can't swap your fork back to air, due to the fact that the spring may scuff up the inside of the stanchion, which would allow air to go to where it doesn't belong.
PerformancePush recommends installing their seal kit at the same time as the ACS3 for the best performance, which is good advice, but I kept the stock seals in place in order to reduce the number of variables I was changing. Based on Push's reference chart, I went with a blue spring, which is the suggested choice for riders between 155 – 175 pounds (I weigh 160 lb).
Without Push's nifty Air Bump Stop that spring rate would likely have been on the softer side of things, due to the inherently linear nature of a coil spring. But, with the air chamber inflated to 25 psi the fork sat exactly where I wanted it to, delivering a super-supple feel at the beginning of the stoke, before ramping up to avoid any harsh bottom outs. I also ended up dialing in a little more low-speed compression than what I was running in the fork's air-sprung configuration. This provided a little more support at the beginning of the travel for pushing into corners or to preload before hitting a jump.
One of the selling points of coil-sprung forks and shocks is the superior small bump compliance and on that front, the ACS3 doesn't disappoint. I was amazed by how responsive the fork felt with the ACS3 kit installed – it takes almost no effort to initiate travel, and I found myself taking lines in the wet that I usually reserve for dry days due to the increased amount of grip. The kit delivered an instantly noticeable increase in traction, a sensation similar to running really low tire pressure. The wheel felt glued to the ground, tracking over every root, rock, and bump in the trail without getting bucked off line.
IssuesI didn't run into any performance issues, but at first the ASC3 made more noise than I would have liked. When faced with repeated large impacts the fork made a loud “thwack” noise that sounded similar to a wooden ruler hitting a desk - you can hear it if you turn the volume up in the video. At first, I thought it was the spring knocking against the inside of the fork's stanchion, so I installed more shrink wrap and a healthy dollop of grease to quiet things down. That made a small difference, but the noise was still present - the culprit seemed to be the air bump stop hitting top of the lower shaft. There's a small bit of rubber on the bottom of the bump stop that's supposed to keep things quiet, but it wasn't working as intended.
Push sent me a replacement Air Bump Stop, which had a thicker piece of rubber in place, along with what seemed to be more negative pressure - it was slightly shorter when aired up to the same pressure as the original. The replacement did the trick, and the noise that had been annoying me before was replaced with a blissful silence. According to Push, if a customer had experienced that problem they would have received the same treatment that I did - a replacement would have been sent out to correct the issue at no charge.
Pinkbike's Take | For riders looking to improve the comfort and traction of their current fork, the ACS3 delivers an incredibly smooth, comfortable ride no matter how rough the trail. However, that ultra-plush performance isn't cheap, and there's also the weight penalty to factor into the equation. Still, it's a very impressive product, and worth considering for those who want to make the switch from air to coil without coughing up the dough for an entirely new fork.— Mike Kazimer |
Mike you should check it out too as his solution is much more simple and usually lighter than stock air-spring systems !
Some of the shit you say is literally baseless.
Yes, the rc3 Evo (i owned one) its a divey fork, but isn't open bath fault. It's just a really bad damper.
Dvo emerald (my current fork) stay high in travel, have strong damping (way better than my fox rc2) and still a open bath fork.
On top of that your comment on going with softer spring for more comfort would probably only result in the fork diving a lot until it gets to the air spring. To which you will tell me you can correct that with compression tuning, to which I'll tell you the same for the CR Conception solution as a good shim stack setup (in his own cartridge for exemple) will sort this out with HSC tuning.
You're most welcome I saved you 200$ or spend the same and have an excellent cartridge instead of stock rubbish found in most forks @pedrosalas7: Like I said, much more simple, 1/3 of the price, lighter than air spring. Exists for 90% of the forks on the market, if it doesn't yet you send your fork and he will make it for your fork. So sure it's you can't control end stroke like the push but that's with 99% of coil spring setup and in this case you also get the weight advantage of air spring, the tracking and begin stroke of spring.
On top of that your comment on going with softer spring for more comfort would probably only result in the fork diving a lot until it gets to the air spring. To which you will tell me you can correct that with compression tuning, to which I'll tell you the same for the CR Conception solution as a good shim stack setup (in his own cartridge for exemple) will sort this out with HSC tuning.
You're most welcome I saved you 200$ or spend the same and have an excellent cartridge instead of stock rubbish found in most forks
Exact same observations are shared by Bike Radar testers in latest comparison 36 vs Lyrik.
With the Charger 1 damper paired with the Lyrik's original air spring I was only running a few clicks of LSC damping before in an effort to get better chatter/small bump sensitivity, but it didn't make climbing or berm-railing very efficient or supportive, and I like to leave my suspension alone as much as possible while riding (I'll firm the LSC for jump tracks and such).
As a consumer building a bike from the ground up, this kit vs a purpose-built coil fork isn't a good buy. As someone with an existing bike and fork, this kit has me begging for a coil in the rear now. I'm stoked as hell to go back to Windrock DH park after getting this upgrade tuned.
The non Evo 55 RC3's were divey. The later generation 2013/2014 solved that problem with a upgraded damper and slightly higher spring rate.
I own both and the 2013/2014 RC3 Ti Evo V.2 is vastly superior to the 2010 55 RC3 Ti.
Got the mrp kit with tunable negative chamber and it's made the difference. Couldn't recommended enough, loads more grip and plenty of support. I can't stand a divey fork
The main difference is in that initial stroke, where the coil spring makes the fork feel more compliant, more responsive to obstacles of all size. That's what was providing all of that traction that let me take stupid lines in the pouring rain. The coil is better at taking the edge of trail chatter.
What's it do worse? Not much - there's a little less mid-stroke support, and racer-types may need to go up a spring rate to get that sporty feel, but it's a good option if you're looking for a plush, grippy feel from your fork.
The other area I find it is good in is in really technical rock gardens--ones where you cant just plow through but you have to make fairly sharp turns. There is a trail I ride with a steep rocky, bumpy, drop to a sharp left turn thats off camber sandy on rock. It's slippery. The fork tracks through that better and I can more easily make the turn. It's a section a lot of people walk or go a into the runout on.
Really those are the two scenarios I notice the difference the most. It added about .75lbs to the fork. The break in on the Push dust wipers seems to be for real. Felt bad at first but it has gotten WAY better.
If I lived in Tahoe for instance, I probably wouldn't get an ACS-3.
The air spring doens't engage until like the last 1/3d of travel so it doesn't really affect the poppyness of the fork or anything like that on small stuff.
I will say, just from the set up, it's not for the set it and forget it type and it takes a little while to get the spring set up proper for sag and negative chamber
Slower speeds it's ok, at pace it's totally sublime. One oddity since mrp ramp fitted feels faster rebound on normal setting.
You can have fancy high dollar suspension with great tolerances, but having crappy valving is critical. In the dirt bike world, very few riders spend money on Ohlins or other suspension when revalving and re-springing the OEM stuff is a much better use of money. Instead of buying a Pike/Fox, etc with valving that would still not be great, I had Avalanche install their SSS shock setup (and soon I'll install their SSS open bath fork setup). My shock is amazing now. Wish I could convert my Revelation to a coil spring with the SSS damping.
I still prefer the fork/shock spring to set the ride height and the damping and internals control the compression and rebound, rather than having the progressiveness of an air spring confuse the situation.
There's basically only one air fork in the motorcycle world that has staying power (KTM's AER setup) because it is simple to set up and still performs very close to a coil fork. However, many people are still converting it back to coil because it works a little better overall. In a few years it will likely gain more acceptance as they iron out the differences.
The Lyrik/Pike/36/34 are so damn good now, and they've come down to reasonable pricing. Even the second tier forks (Yari, etc.) are amazing (easily the equal of their first tier products from a few years ago). I'm a set/forget type of rider, don't fettle too much with settings. On that front, the coil appeals - but then again, I don't really need to do much regarding air spring pressure either.
Between the price tag and the subtle performance differences/advantages, this seems to be a niche product.
I've been very pleased with pike/lyrik forks for years. I put on a coil rear shock on and suddenly I'm considering this conversion for my lyrik.. I'm going to try the new 2019 air spring ($50) when it comes out before I do the conversion to coil.
What do i like about it? Never having to wonder "is my pressure right? Does it need a little more?" etc etc.
Set. And. Forget.
Truth be told i could probably drop a spring rate for an even more supple ride but i do like it as is. And also enjoy having a little more weight (we are talking grams, people) up front as well.
My next fork will be a coil out of the box. And even if Fox start making them again, it wont be one of theirs.
Also, there is a huge difference in spring rate and travel between a MTB fork and an RC car.
Why people buy a brand new fox 36 for like £1100 and then throw a 300 doller coil in it is stupid and makes zero sense.
That's my 2 cents worth
Ps am biased i run full ohlins coils on my slash.
A few of the places I've seen give options for travel, but not for spring rate. And if it does come standard, what colour do you get?
Cheers
It does seem like RS fork owners are getting loads of options for their springs now. Which is nice considering these are often OEM forks. RS updated their air spring, Vorsprung has their Luftkappe and now Push has the coil sprung conversion. Would be interesting to see a direct comparison between the three.
R.E. rattle - I had the same problem with mine.
the spring is the culprit - if you pull the bottom out control all together and run the stock air cap instead (obvs with no air added) it'll do the same.
Its because the spring is designed for the Pike also, so slightly smaller dia.
If you put 2 new spring isolators on the spring top & bottom that will quieten it up lovely.
Gimme a shout at TF Tuned - I can hook you up.
My Fox 36 RC2 was night and day better after I did the conversion and I made gains in cornering and jumping while also feeling less fatigued after long rides. It's the real deal.
They'll figure it out.
Small bump compliance is marketing but highly subjective so it works, it does get thrown around a lot though. I'm now waiting for tire companies to start using it to market their tires - (which is true, depending on tire compound & pressure, definitely helps with small bumps)
it's not marketing, it's a feature of good forks. if a suspension maker using the fact that their fork has a good quality is marketing, well then i guess everything is marketing, and now the term has lost all meaning
are you trying to say that all forks have SBC? yes, all forks have some. but only good forks that are set up well have good SBC. you'll know when you suddenly stop thinking about your fork when you're riding because it's smoothing things out perfectly. I guess you haven't gotten there yet. maybe one day.
Will this work with a Lyrik Dual air 160/130mm? If yes, I am very interested.
Can't we make a spring from air?