TEARDOWN | FIRST IMPRESSIONS
SR Suntour Durolux EQ
EQ Air Spring
Say hello to the new SR Suntour Durolux RC2. It shares the same robust 36mm crown steerer unit (CSU), with the hollow aluminum crown, as its predecessor. Crisp grey colour aside, the magnesium lowers, with their air-bleeder screws, are unchanged. It has the same highly adjustable RC2 PCS damper. Heck, it even has the same 800 USD SRP.
The significant change is to be found inside the air system. While SR has long relied on a coil negative spring configuration, with four separate spring rate options, the new Equalizer (EQ) air system follows the familiar architecture first laid out by the RockShox Pike fork* with a dimple, or transfer port, in the stanchion to allow the negative and positive air springs to self-balance.
With EQ, Suntour takes a fork that already delivered performance beyond its price and makes it initially suppler, notably smoother, and significantly quieter than the last generation. All that without making it any more difficult to service or more expensive for you.
*Or Fox Float air shock - we'll accept either argument.
Straight up, I really want to dislike the EQ air system. I've always thought the biggest issue with forks using coil negative springs is that companies didn't offer multiple rates and the biggest issue with Suntour specifically is that riders didn't know that they needed to swap rates based on their weight, ride preference, or travel setting.
I've run my Durolux everywhere from 100mm to 170mm of travel just by quickly dropping the lowers and adding or removing clip-on travel spacers. It's a sub 10-minute job, including sorting tools and cleanup, that costs next to nothing. With the EQ that's all ruined as different air shafts are required to change travel while maintaining the orientation of the air transfer port. Those of us who like playing with fork travel may lament the additional expense and time for swapping air shafts, but for the majority of riders this is a 100% improvement without downsides.
One thing to note is that the requirement for the air transfer port in the spring-side stanchion means that the EQ air spring is not a simple retrofit for older SR chassis. It would be possible, and perhaps even cost-effective, to upgrade the air system and CSU at the same time v. buying a new fork, and any Suntour service outfit will be able to quote you on the work soon.
If you enjoy riding the Durolux chassis in a lowered format, Suntour has us looked after as well. Since the EQ air systems share many parts between different models, the air shafts for shorter XC and trail forks can be used in the EQ Durolux. At some point in the future, I'm looking forward to trying the new EQ system in a Durolux dropped to 100mm or 120mm on the front of my Waltworks.
The Durolux continues to be delivered with three different damper options. The basic RC (rebound & compression) is an OE level product that also loses the hollow crown. The R2C2 (high & low-speed compression and rebound) is the highest end damper and by all accounts, SR Suntour has long resolved the damper noise issues I experienced in 2016.
This is my third experience with the RC2 PCS damper, counting my wife's Auron, and setup is straightforward as usual. I'm still playing around with settings v. the new EQ air spring but I'll have some base tune information in my full review once I've had plenty of hours on the fork.
Two riders meet on the trail heading in opposite directions. Some friendly chirping ensues and I hear the words: "Fresh fork! Does it creak yet?" They share a hearty laugh and head in their respective directions. I chuckle. Now that I've heard the same joke multiple times a week for over a month I'll admit it's starting to get a bit old. Not as old as constantly dealing with creaking CSUs themselves mind you, but old.
I have no doubt that SR Suntour - and Ohlins, MRP, CaneCreek, DVO, etc - will all have 38mm-stanchioned single crown forks sooner than later. Heck, does Manitou regret making the Mezzer's measuring 37mm instead of 39mm? Current cosmetic considerations demand it. It's the damn 35mm handlebar story all over again.
I can't guarantee that the CSU on the Durolux won't eventually creak. I'm personally of the opinion that all pressfit interfaces will start to make noise at some point if being ridden hard on the North Shore. I also don't think of bike parts, aside from high-end hubs maybe, as life-time purchases - everything has a lifespan. But, I've seen used Suntour forks abused by Brett Tippie, Garrett Buehler, and James Doerfling that are dead silent with original crowns.
I'm also not going to tell you the e-bike-rated Durolux chassis is the stiffest on the market. But I'd have to reserve an over-the-top incredulous look for anyone claiming it isn't in the same category as any of the big-hitter single crown forks on the market. I'd compare it favourably with the Manitou Mezzer chassis, albeit at a 200-gram weight penalty.
Anyone with enough size or aggression, or that is riding tracks where a Durolux isn't enough chassis - should just buck up and get a dual crown fork*. There are plenty of 29" wheeled bikes now, like the Enduro or Megatower, that have fully embraced the freeride ideals of yesteryear - a DH bike that can be pedaled uphill - and I routinely wonder if the only thing keeping riders from doubling up those crowns is the extra cost. I wonder if we'll look back at 38mm chassis single crowns in a few years and wonder why brands didn't just make dual crown versions of their excellent 35mm and 36mm chassis long travel single crown forks.
Suntour is not currently selling an EQ version of their RUX DH fork or a RUX 29er, but presumably product updates are coming, based on a look at what their team riders are running. I'd look for it to be an option that's easily lowered as demand for 170mm+ dual crown forks will grow.
*After checking that it's approved by the manufacturer.
One feature of the Suntour forks that has really grown on me since my first impressions in 2016 is their QLOC quick-release axle system. The stated goal of QLOC is quick wheel removal, and it certainly accomplishes that. A feature that is desirable for some folks packing their bikes inside Sprinter vans or in the boot of their hatchback after every ride.
While I would still love to see a cleaner looking bolt-on version, for those of us who'd rather pull out a 5mm or 6mm hex, the big win for me with QLOC is that the magnesium dropouts don't need to be threaded. I don't know much about manufacturing magnesium lowers beyond the fact that it's really easy to mess it up and having seen some magnesium dropouts flaking apart with porosity I think any design that simplifies the lowers' manufacturing is a solid win.
Intermission - Where's Jeff?
Over the years, I've met a plethora of interesting people taking Jeff's Bikeroom courses. From perfectionist road cycling nerds* Phil & Peter Liu of Veloholic Cycles to the incredibly sweet Mike McIntosh who I think about every time I see a driver no-look-open their door as I ride past parked cars going to and from work using North Vancouver's proven-deadly patchwork of cycling infrastructure.
It was great to have Jason tool up so I could hold the camera while Jeff was busy finishing up the last day of his latest series of Bikeroom classes.
*Said with much respect.
I've known Chris Doll since he was a customer at Different Bikes over a decade ago. He wears a lot of hats. He's a father of three, co-proprietor in the Local Life Juice Bar with his wife Jacqueline, and he's a high school shop teacher with the goal of adding a mountain bike mechanics program to the curriculum.
I've mentioned the opportunities for bike mechanics before here on NSMB.com - with A Mountain Bikers Retirement Plan - and I think it's awesome to see it added as a trade that kids can explore. Thanks Chris!
The new EQ air system really is better from an out-of-the-box-performance perspective and more importantly, it's dead quiet. I could argue if a little negative spring noise is bothering you there are other issues, but if SR Suntour can sell a fork that performs at the highest level but also is quiet like a top-end product, it will help them make inroads with the Fox and RockShox crowd. Particularly when you compare what you're getting from either brand at 800 USD.
I'm certain there are riders who are faster downhill on a top-end Ohlins, Formula, or other boutique fork, and if you have the money, then why not? But for a rider at my level, I'm not giving up anything performance-wise while riding an RC2 Durolux EQ compared to more expensive products.
On my second ride, I had a friend ask me if I think the Manitou Mezzer is a better fork. It's lighter, it's a least as stiff, it's badass looking, it's significantly more sophisticated in terms of tuning, it rides much higher in its travel thanks to IRT, and some riders are going to prefer that. Could I justify the 200 USD price difference to someone else? Absolutely. Could I justify it for myself? Harder to say.
I had months of great riding on the Mezzer and my first impressions here are based on my previous experience with the chassis and damper and a few rides on the new EQ air system. Certainly I'll be comparing the two extensively, along with my previous-gen Durolux, for the final review.
The basic idea of min-maxing is that I can save money on certain areas of my bike to boost up performance where it really counts. There are, however, some products like Magura's Trail Sport or SRAM's Code R brakes, the WTB Vigilante High Grip tire, the PNW Rainier dropper post, or Sensus Swayze push-on grips, where choosing the budget option doesn't give up anything while saving cash on a well-supported high-performance product.
On my Marin right now I'm running this EQ-equipped Durolux RC2 fork, at 170mm travel, as well as The Only Drivetrain That Matters, and combined - fork, cranks, shifter, derailleur, chain, cassette - that setup costs less than just buying one of the latest and greatest top-end 38mm forks. Now, I'm not racing, I know the limits of my courage and abilities, but I'm giving up nothing in terms of fun and riding all the tough terrain I want to.
I have high expectations for the new EQ air system and this chassis I'm very familiar with and that's strictly focusing on performance. Durolux is also a contender for the easiest home maintenance. I'll be riding it into the ground for a follow-up review where I'll also teardown the damper to see the newer PCS guts. In the meantime, there's a bunch more information at SR Suntour.