Review: Suntour Auron PCS RC2 fork

By Eric McKeegan

The Auron fork isn’t new, but the PCS damper is a new addition to the Auron lineup. PCS stands for Piston Compensator System. The piston in question keeps the air and oil separated inside the damping cartridge. The piston is spring-loaded to be able to move (compensate) for changes in oil volume due to heat and pressure buildup during long descents. When air and oil mix inside a fork, bubbles form. Bubbles and effective damping can’t coexist. The PCS damper can be tuned, serviced or rebuilt without any specialty tools.

The chassis is a combo of a hollow crown, 34 mm stanchions and magnesium lowers. There was a lot of back-and-forth with Suntour about what fork would be most applicable as an upgrade, and in the end a 100×15 mm axle was deemed most appropriate. Stock travel is 130-150 mm, in either 27.5 or 29. This is a 29er fork knocked down to 120 mm to match up with the Soma Juice and 27plus tires. Suntour just released a 29/27plus version of this fork with 35 mm stanchions and Boost spacing, should that be your jam.

The high and low speed compression adjustments are opposite of what you’ll find on most forks. The high speed compression has a lever with five settings, and low speed is on a small dial with 17 clicks. Since low speed is what works as a pedaling platform, I would expect that to be on the lever. In practice, I was able to dial in both to my preferences and left them alone after that. I did notice there wasn’t a very wide range of adjustment, and nothing that resembled a lockout. This could be a problem with riders at the heavy or light end of the spectrum. What isn’t a problem is the coil negative spring, which comes in three different stiffnesses for flyweights on up to Clydesdales.

The fork comes stock with two volume spacers, which was just fine for my 160 pounds. The air spring does all the right things at all the right times. It is supple but has enough mid-stroke support to prevent wallow. The fork ramps up enough to prevent hard bottom out.

The chassis hasn’t changed much from the last time I reviewed an Auron, and it is still as stiff as any 34 mm fork on the market, save for the much heavier and expensive Ohlins RXF 34. The Q-LOC axle is still the fastest thing on the market, at least once you get the hang of it. One downside I noticed this time around is the handle can be closed without the collet being in the open position, which could lead to a situation where the axle looks secure, but could slide out while riding, so pay attention! The instructions do say to open the collet before sliding it into the fork, but even I managed to close it improperly once.

It wasn’t that long ago that riders were looking to upgrade from a Suntour fork. Now with multiple wins in downhill, cross- country and enduro at the highest levels, more riders are looking to upgrade to a Suntour fork. The Auron is a solid choice for 29er trail bikes that came stock with 32 mm stanchioned forks. With an easily serviceable damper, plenty of tuning options and a sturdy chassis, the Auron is a viable option in today’s crowded trail bike market.

Buy it
-easy to service
-negative spring fine tuning
-upgrade from a skinnier trail fork

Skip it
-need a firm lockout
-only ride name brands
-want a color other than black

Price: $700