PUSH Industries ACS3 Fork Coil Conversion Kit in review
In the “The Lab” we present the latest products and put them through their paces for you. Some undergo long-term tests, while we check others out only briefly. This time we reveal how the PUSH Industries ACS3 Fork Coil Conversion Kit fared.
When it comes to suspension forks, all manufacturers have one goal in common: they want to develop air springs with that buttery smooth coil feeling. So why not use a steel or titanium spring in the first place? Because air springs are easier to adjust and can be finely adjusted to the weight of the rider. They also offer a clear weight advantage and allow you to tune the progression of the travel by adjusting the volume of the air chamber. With the only disadvantage of weight, the PUSH ACS3 wants to combine the many perks of air springs with the one massive advantage of steel springs: they don’t suffer from the stiction and friction of seals and therefore react much more sensitively to small bumps. With the ACS3 kit you can convert any RockShox Yari, PIKE or Lyrik, as well as all FOX 36 forks, to a coil spring. Together with the steel spring, PUSH use an additional air spring which is actuated in the last third of the travel. The so-called Air Bump Stop spring increases the progression of the otherwise linear fork and can be fine tuned with a shock pump. Anyone who has ever performed a lower leg service on their fork will be able to install the € 329 PUSH ACS3 kit. However, if you don’t feel comfortable with that, we recommend you get the kit installed by a professional.
Without a sticker, from the outside the ACS3 Coil Kit is only recognizable by the blue nut and silver ‘Push’ valve cover.
The rubber buffer of the Air Bump Stop spring is designed to reduce noise when the progression spring is actuated. Nevertheless, you can still hear a clicking noise on hard landings and big hits.
In addition to the steel spring, the ACS3 uses an additional air spring for a progressive spring rate at the end of the travel. Its stiffness and hence progression can be easily adjusted.
We installed the PUSH ACS3 kit in a 160 mm RockShox Yari RC with the old Solo Air cartridge. The conversion improved the response of the fork enormously. The modified fork now neutralises even the finest gravel, brake bumps and root carpets and transmit way less vibrations to the hands. It simultaneously provides good support when jumping off ledges and pumping through berms and never dives too deep in its travel. With big hits you can hear a clicking noise when the Air Bump Stop is engaged. Apart from the noise, the Air Bump Stop works incredibly well and with silky smooth performance that remains well controlled at the end of the stroke.
The PUSH ACS3 Fork Coil Conversion Kit significantly improves the sensitivity of your air fork. Models with relatively small negative chambers will particularly benefit from the conversion and perform a lot better than with the original spring, reducing arm pump and increasing front wheel grip. On high-end forks with modern, large negative chambers, the difference won’t be as significant, making the € 329 kit a good investment only for real coil freaks.
Tops
- butter smooth response
- finely graded spring strengths
- low maintenance
Flops
- loud on big hits
- re-conversion to air spring not advisable
Tester Sarah
Duration 7 months
Price € 329 (kit), 85 € (spring)
More info pushindustries.com