The probation period is over, what was once ‘new fangled’ has now been accepted as the standard. Narrow – wide works and riders the world over are throwing away their noisy and temperamental bash rings to run a sexy open chainring setup. Not only does losing the chain-guide result in a simpler drivetrain but it also sheds a chunk of weight from the bike. Once the reserve of SRAM’s mighty but very expensive XX1 drivetrain, the narrow wide tooth profile has filtered down to many companies with CNC machines, and even though there is talk of unlicensed application, there are now many more affordable options available to extend and simplify a 1×10 setup.

The latest company to offer what will surely become the ‘essential’ alternating tooth chainrings is the mighty HOPE Technology with their Retainer Ring. Thinking bigger, they have coincided the release with another product, the T-Rex Ratio Expander, providing a complete solution for those looking for more range from their 1×10 setup, stepping up a gear to 11-40. We checked out some first production rings to see how they performed.

The Retainer Ring brings narrow wide technology.
The Retainer Ring brings narrow wide technology.

Hope Retainer Ring – £45

With many companies now offering CNC’d chainrings there is already a lot of competition in this sector, but HOPEs Retainer ring has a few well thought out features that lift it above the crowd. We were sent a 30 tooth ring to test (available in 30,32,34 and 36), and the innovative features were evident from the moment of fitting. Every time you fit a 1xX setup, the process is normally preceded by a hunt for suitable length chainring bolts and backs, and often with some creative filing! With the HOPE the chainring bolts screw directly into a machined thread in the chain ring, so no female bolt is needed making it much less critical of bolt length. This will also limit the chances of seized chainring bolts when it comes to future removal, a nice touch!

The chainring bolts screw directly into the chainring, no female bolt is needed!  A nice touch!
The chainring bolts screw directly into the chainring, no female bolt is needed! A nice touch!

The retainer ring can be used with 1×9, 10 and 11 speed drive-trains and features slightly taller teeth than most for even better retention. HOPE have also incorporated knowledge gained from riding in grimy UK mud and have machined flutes at the bottom of the teeth to help shift mud from the chain. While mounting the ring, it looked like the spider of the XT cranks would interfere with the chain on the tiny 30t. However, HOPE had already though of that and machined in lugs to keep the chain running a safe distance from the arms of the spider. There is not much technology you can squeeze into a chainring, but this on is very well though out, and fitment was a breeze! The chainring is available in 104 BCD in Black, Silver and Gold and weighs in at a featherweight 42g for the 30T

On the Trail!

The 30T sample we were sent has been running perfectly over the last 3 weeks of testing. Not one dropped chain or issue. The Narrow – Wide profiled teeth grip the chain tenaciously and the drive-train has been quiet (you need to combine these rings with a clutch mech) and reliable. Whether the retention will be as perfect when chain wear starts to become an issue is still to be determined. Even repeated attempts to upset the chain, spirited back pedaling and aggressive maneuvers, could not shake the chain free of the Retention Rings grip. The 7075-T6 aluminium provides a good blend of light weight and strength, and the hard anodized finish seemed durable. Despite the perfect performance from the ring, we would still recommend a light top guide if you are racing against the clock as racing puts very different demands on a drivetrains! For all round riding though, no chain device is needed! We will let you know how it performs over the long term!

Hopes new T-Rex Ratio Expander brings 11-40t range to 1x10 drive trains.
HOPEs new T-Rex Ratio Expander brings 11-40t range to 1×10 drive trains.

HOPE T-Rex Ratio Expander £60

The HOPE T-Rex Ratio Expander allows you to upgrade your existing 11-36 10spd cassette to give an 11-40t range. The T-Rex simply installs behind your existing cassette and replaces one of the smaller sprockets, usually the 17t. Now, there are two schools of thought when it comes to Ratio Expanders, the first are looking for more speed, the second are seeking easier hill climbs. Often derided by those ‘stout of leg’ as a wimpy addition, this is totally missing the point!

Having a bigger range of gearing at the cassette allows you more control over your front chainring size. Here in Scotland, a lot of the local riding is a ‘winch and plummet’ style, fireroad climbs and super technical descents. This is doable, but hard work with a 34/36 ratio, but dropping to a 30 or 32 can see you spin out on the super fast flat out sections. By fitting a 40t T-Rex Expander you can up the front chainring to 34 or even 36, retaining the climbing ability but providing an extra gear for the fast sections, allowing you to drop your mates on the pedals.

The T-Rex Expander can either provide a bigger climbing gear, or allow you to run a bigger chainring for more speed!
The T-Rex Expander can either provide a bigger climbing gear, or allow you to run a bigger chainring for more speed!

On the Trail

When HOPE first presented the T-Rex, it had 42 teeth, but in testing they decided that 40 teeth was enough and offered a better solution to the rider. This means that even short cage mechs can work with the extended ratio, and you do not have to go crazy on the B-Tension screw. Surprisingly Hope also decided to not make the T-Rex a universal fit, so you will need to choose either a SRAM or Shimano Version. HOPEs reasons for this were that by making the rings specific, they could more precisely match the tooth profiles and shifting points on the cassette, improving performance. We have only had the T-Rex fitted for a week now, but the performance has been perfect, you hardly notice the loss of the 17t cassette ring and the greater range at the top is certainly noticeable. Shifting has been faultless onto the big ring, and it all looks super bling. Setup was very easy too, with just a slight adjustment to the B-Tension required to raise the mech off the ring.

Bottom Line

It is early days in the testing process but so far the pairing has been faultless. When you look at the cost of an XX1 or X01 drivetrain, for just £110 you can have almost the same range with HOPEs setup. If you have not switched to narrow/wide yet, when your chainring wears out, give it a go! It is quieter, more reliable and simpler! Compared to X01 and XX1, the HOPE setup uses cheaper cassettes (you need either Shimano XT or XTR 11-36 10spd cassettes, or SRAM PG1030, PG1050 or PG1070 11-36 cassettes) and is the perfect solution for those looking to change to 1×10 while keeping a wide range of ratios. For pure performance, X01 and XX1 will always be king, but if you go through a lot of cassettes and don’t like the idea of stumping up £300 for a new XO1 cassette every season, this could well be the solution for you!

Words and Photos: Trev Worsey

Did you enjoy this article? If so, we would be stoked if you decide to support us with a monthly contribution. By becoming a supporter of ENDURO, you will help secure a sustainable future for high-quality mountain bike journalism. Click here to learn more.