Ridley Helium SLX eTap review

Lighter, rarefied Helium

Our rating 
4.5 out of 5 star rating 4.5
GBP £7,400.00 RRP | USD $7,500.00

Our review

The Helium SLX matches exceptional climbing pace with glorious ride quality
Buy if, You want a wolf in sheep’s clothing, as those simple, classy looks cloak an aggressively fast, but refined ride
Pros: An exceptional frameset with breathtaking acceleration that is well matched by its wireless groupset
Cons: 4ZA’s wheelset performs well, but can be a little grabby under hard braking
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The Helium SLX is the most successful combination of a Ridley frame with in-house brand 4ZA finishing kit and wheels so far. It not only looks like a bike designed to romp through rolling countryside and soak up abuse, it rides like one too, only faster, and with more ease.


The 4ZA Cirrus Pro 30 wheelset is a £500 option, replacing the Fulcrum Racing 5s listed, and feature carbon rims spinning on DT Swiss 240s hubs. The internal width is conservative compared to current trends, but does expand the Vittoria Corsa G+ 25mm clinchers to a useful 26mm, creating greater volume, more usable grip and comfort.

Their shallow, blunt profile is agile and aerodynamically efficient, and the accelerative difference light wheels can make to a bike can never be overstated. Fitted to the Helium SLX’s sub-1kg frameset and premium componentry, the result is impressive.

Increasing pace needs a mere thought and increase of pressure on the pedals, but it’s the way this Ridley coaxes you to greater performance with seemingly minor inputs that becomes addictive.

The 4ZA Cirrus Pro 30 wheelset is an additional extra

Long, steep climbs that are usually a grind became gradients to be attacked. On a local rollercoaster stretch of road, sustaining speed over every switchback is nigh on impossible except for the days when everything clicks. On the Ridley, that was every day.

Since what goes up must plummet down, the Helium SLX is a stable descender, a little active at the front on rough sections, but nothing to be concerned about.

Flatland velocity is even easier to generate, and simple to maintain. But all this speed would be less accessible without fine ride quality, and here the SLX builds on the cosseting characteristics of the old Helium SL. With pressure at 90psi, the tyres suck up potholed roads like 35mm ones at 40psi.

One-piece bar and stem combos can be a recipe for harshness, but 4ZA has created a buzz-killing setup, with a comfortable anatomic drop, ideal hand positions, and aero tops that are grippy enough when climbing.

Increasing pace needs a mere thought and increase of pressure on the pedals
Russell Burton

Fitting a screw-in BSA bottom bracket shell to a press-fit 30 shell and choosing SRAM’s 24mm GXP axle is unusual, but doesn’t unduly affect the Ridley’s performance. It should ease maintenance though, and wider spaced bearings are always a good thing.

SRAM’s eTap groupset excels again, creating clean lines and ensuring slick, fuss-free shifting, and with the 52/36 and 11-28 combinations fitted here, perfect race-ready gearing.

The hoods are beautifully ergonomic, and the Red rim calipers are still some of the best available, with great power and modulation.

Zipp carbon brake pads handle stopping duties well, with decent initial bite and progressive power, although under hard braking, I did find the rims a little grabby with some squeaking. Vittoria’s Corsa tyres seem to roll fast, and handle predictably, save for the noise they make when cornering.


There are no real aero considerations here, the fork legs have truncated profiles, but the frame tubes are otherwise shaped to be laterally rigid, efficient and compliant, which is a fairly all-encompassing range of qualities, but ones the Helium SLX owns.

Product Specifications


Name Helium SLX eTap
Brand Ridley

Available Sizes XXS XS S M L XL
Rear Wheel Weight 1370
Wheelbase (cm) 98.5
Top Tube (cm) 56
Standover Height (cm) 80
Seat Tube (cm) 51
Chainstays (cm) 41
Bottom Bracket Height (cm) 27.5
Wheelset 4ZA Cirrus Pro 30
Weight (kg) 6.3
Trail 7.1
Stem 4ZA Ursus integrated
Shifters SRAM Red eTap
Seatpost 4ZA Cirrus Pro carbon
Seat Angle 74
Saddle 4ZA Cirrus Pro
Rear Tyre Vittoria Corsa G+ 700x25mm
Bottom Bracket SRAM GXP
Rear Derailleur SRAM Red eTap
Headset Type Integrated
Head Angle 72
Handlebar 4ZA Ursus integrated
Front Wheel Weight 1070
Front Tyre Vittoria Corsa G+ 700x25mm
Front Derailleur SRAM Red eTap
Frame Material Helium SLX, HM unidirectional carbon
Fork Offset 3.75
Fork Helium SLX, HM unidirectional carbon
Cranks SRAM Red eTap, 52/36
Chain KMC X11
Cassette SRAM Red 11-28
Brakes SRAM Red
Frame size tested M