We Go Behind the Scenes of the SR Suntour Durolux EQ R&D.

First spied way back in February, SR Suntour updated their Durolux fork to sport a better negative air spring, adjustibility and less trail chatter.

Pete caught up with SR Suntour’s Christoph Boesl and Arnaud Hacquard to chat through the development of their new Durolux EQ fork and how they go about offering something altogether different than other fork manufacturers.

What made you decide to make update the Durolux fork?

CB: According to our Refined Simplicity approach we´re continuously striving to improve our product and make it more simple in terms of handling for our wide range of customers. And of course we are competing in a challenging market in many ways that doesn’t allow for taking a rest.

In this case the new EQ system (air negative spring) allows for a bigger air volume that gives us more room for adjustability from comfort (more linear) to a very sporty setup with increased progression.

Also the range based on riding style and rider weight is now bigger so we can replace three different coil negative springs this way.

Last not least the ratio between positive and negative chamber is always ‘ideal’, which gives the rider always best riding performance (20-30% less chatter as a result on the handlebar measured by data acquisition).

Once you had made that decision, what happens next?

CB: The starting point to change product comes from different sources’ feedback.

Experience and feedback from business customers (OE), media tests, our World Cup riders and ambassadors and of course also private customers we´re tracking by our service, via social media or which we meet out on events. Last not least we ride ourselves. We discuss in product meetings on a global level and then we issue a whitebook of what we want to achieve with it, mainly driven from our offices in Taiwan, USA, France, Italy and Germany. With this feedback the task goes to our R&D office in Bologna for final concept and design.

Who is involved in that process and what do they do?

AH: Different categories of people are involved in the process. Sales, marketing, service and engineers, people from OEM side and aftermarket side and then some experienced EU and North American SR Suntour employees in addition of some official sponsored riders for the first samples testing. We can collect the first feedback and share with R&D colleagues about what is positive and what should be improved or modified.

The idea is also to test durability with different type of riding and to have different categories of users to give their impressions. This way we tend to make forks which can fit all type of users. Of course also getting data and facts in lab and field plays a big role in the development process. We want to proof what we feel and replace product only if we made it better.

How much of the development process is done in-house?

AH: 100% of the development process in done internally. From first drawings up to the production stage.

Design and development coming from mainly European side from Italy and France in close cooperation with our head of R&D in Taiwan, final engineering done for production by our R&D in Taiwan.

What did you know you did and didn’t want to do with the Durolux?

CB: Improve, but keep parts and handling as simple as possible. On paper you can have the best performing product, but if it´s too complicated to adjust for the majority of people, the final result on the trail might not be satisfying. A good example is the R2C2 cartridge. 4-way adjust is complicated especially as you cannot feel the high speed on the parking lot. So we make it easier by only giving five and four steps on high speed compression and rebound respectively.

Same for the service and the cost involved, basically every trained dealer should be able to run a good basic service at low cost with as few special tools as possible. One of the reason besides durability to go with the PCS concept instead of bladder-based cartridges.

How do you ensure your forks stand out against the competition?

AH: What we are aiming for is offering high quality products, simple to set and maintain, at a decent price. We focus on offering the best quality/price ratio products and this is where we are.

PCS in 2016 was our own way for good reason, competitors had to follow.

We also integrate detachable fenders and offer mounting points for city fenders/ e-bike commuting for most of our MTB/E-MTB forks.

How did you achieve that with the Durolux EQ?

AH: The new Durolux EQ fork versions (RC2 and R2C2) offer new features and better performance with no increase of the recommended retail price. We even offer a new RC PCS (cartridge with low speed rebound and compression adjust and forged crown instead of hollow crown) version for 639€ for those who are on a budget but want to benefit from the new EQ system.

Did you make any changes to the PCS for this fork?

AH: The R2C2 PCS cartridge coming with the new Durolux EQ offers the latest update. It is a new rebound piston part which offers a faster recovery on the high speed rebound management.

How do you adapt your Refined Simplicity template for a new fork?

AH: As mentioned before. We want our products to be simple in terms of handling for any customers. The fork has to be easy to set on both damper and spring side. An example, we designed the R2C2 and RC2 PCS dampers so we can also offer a readable high speed dial, with a minimum amount of positions and giving a clear indication of where you are in the range. Beside that, the product has to be QSP (quick service product) which means it remains accessible for maintenance, with no specific tools required and less time to spend wrenching.

How many prototypes did you have before you settled on the production chassis?

The development was mainly done on the stanchion (transfer port), negative spring assembly and volume spacers. So we didn’t have many prototypes for the complete fork as the chassis was already finalized and produced with the coil negative spring version of the Durolux36 Boost.

Beyond prototypes, what form did your testing take?

CB: We have R&D staff in different countries and most of our mechanics in the different offices were former riders or are experienced in supporting our WERX teams even on the World Cups.

So basically, this is the chronology for the testing step:

1- Virtual testing and calculation in simulations

2- Making sure together with some selected riders and staff to put as many kilometres on each product as possible – testing of initial feel, durability and longevity, basic functions

3- Refinement by getting input from high level WERX riders for example in WERX camps

4- Refinement also for the target customer by ourselves, but also by gathering early feedback from OE customers

Favourite moments?

CB: Every time somebody is having a good time with our product you can call it a favourite one. We´re really following a passion and shared good times are the best.

Any disasters?

CB: No disasters, but taking part in such a process right from the beginning is both boon and bane as even suspension right from the beginning is not always smooth business. But very grateful though, anything else would be a complaint at the highest possible level.

Anyone to thank?

CB: Honestly, all the bike riders out there, no matter if electrified or not, no matter if off-road or on-road. I guess we´re not automatically better people, but we´re sitting on the best means of transport.

Gives you fun, supports your well-being, protects our environment if handled carefully. And this is what our company wants to promote and support.

Check out the SR Suntour Durolux EQ fork on their website here.

Read all our product development interviews on our Features page here.