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e*thirteen Sidekick Hubs Promise to Eliminate Pedal Kickback with ‘Revolutionary’ Drive System

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A quick glance at the state of the mountain bike in 2024 will reveal a lot of high-pivot designs. One of the motivations for the latest crop of high-pivot bikes is their ability to mitigate chain growth and pedal kickback – but what if you didn’t need an entirely new frame design to do it? What if it was as simple as changing your hub?

That’s what the new e*thirteen Sidekick hub promises, well, that and more. By decoupling the drivetrain from the rear wheel when coasting, the Sidekick system claims to reduce drag, noise, and vibration while improving suspension performance by “eliminating pedal kickback in nearly all situations”.

Sounds good? Let’s dig in.

How Does Sidekick Work?

Sidekick starts with a proprietary freehub mechanism that contains an extra pawl. The pawl is on a ‘timed pusher’ which allows the drive pawls to retract from the ratchet ring when coasting. Essentially, the drive pawls can slide up and down ramps on the pusher a certain amount before sliding all the way up to engage the drive ring. But until the drive pawls engage the drive ring, the wheel is free to rotate, separated from the drivetrain.

For the system to work, there has to be a deadband that allows the wheel to rotate before the pawls engage. Since not all riders and frames will need or want the same amount of deadband, it can be changed without tools from 12º to 15º or 18º.

Benefits

To validate the system, e*thirteen has done extensive testing with a team of extremely talented racers including Aaron Gwin, Rónán Dunne, Rémy Métailler, Fabien Barel, and more. Using a BYB telemetry system with a 1000Hz/sec sampling rate, e*thirteen found that the Sidekick allows riders to spend 7% more time in the mid-stroke of the suspension range (11-70%), while allowing 44% more (cumulative) use of the shock travel in that range.

Sidekick was also responsible for 20% less crank movement than a traditional hub, which is where the elimination of pedal kickback comes into play.

Claimed Rider Comfort & Speed Benefits

  • Assists riders to maintain a neutral position on downhills
  • Flat pedal riders will experience less kickback at the pedals, providing a planted feel with more comfort and control
  • Eliminates drivetrain clatter and chain vibration when descending
  • Allows for smoother and quieter shifting 
  • Whisper quiet when freewheeling
  • Reduced drag equals free rolling speed

Claimed Suspension Performance Benefits

  • Eliminates pedal kickback in nearly all situations, giving a “chainless” feel while descending
  • No change is needed in rear shock compression and rebound tune
  • Simplifies suspension setup window by allowing free suspension movement (no pedal kickback!)
  • More active suspension while braking
  • Spend up to 50% more time in the mid-stroke (sweet spot) of rear wheel travel giving the feeling of more available travel

How Does Sidekick Compare to Other Products like Ochain?

I asked this question to e*thirteen co-owner and engineer, Greg Thrash, since it seemed like two products with a very similar goal. According to Greg, “the most significant difference is how the two devices mitigate kickback… with Sidekick, the cassette has to rotate through the deadband before the ratchet can engage, so there is zero resistance to chain movement during that period. With O-chain, those movements are resisted by a spring. So fast, dramatic suspension events that feed tension into the chain don’t affect the suspension with Sidekick, whereas with O-chain, they may be blunted by the spring but are still present.

A secondary effect, but probably what you notice the most, is that the normal chain vibration and noise you perceive as you ride over rough surfaces just isn’t there since the cassette can rock on the axle freely both forward and backward without any intermittent ratchet engagements.

On top of that the hub is nearly silent. There is a single pawl in the system that makes it work, but it has a very light spring activating it, so you can’t hear it operating over the sound of your tires on the ground.

Between the super low drag pawl and your suspension working better, your bike seems to roll super fast, corners better, carries more speed; everything seems to work better.”

Who is Sidekick for?

Many of those reasons are also why e*thirteen is marketing this to more than just downhill racers. Advertising it as beneficial for everything from aggressive short-travel trail bikes to full DH bikes, as well as Class 1 ebikes, the Sidekick system has benefits for a wide range of riders. Namely, improved suspension performance, lower drag, less noise, and reduced fatigue.

What About High Engagement Hubs?

It seems the bike industry has been pushing relentlessly toward higher and faster-engaging hubs. The Sidekick system seems to fly in the face of that, so what gives? According to e*thirteen, while those high-engagement hubs might help you out of a tight technical spot, they won’t improve suspension performance. In fact, they might hurt it stating, “while coasting at 15 mph (25 kph) a hub with 1-degree engagement can engage over 1000 times per second, leading to significant pedal kickback and poor suspension performance. A hub with 18-degree engagement in the same scenario can engage over 60 times per second, also resulting in a high likelihood of pedal kickback.”

Hub Construction

None of this matters if the hub isn’t up to the task, so e*thirteen spent a lot of time obsessing over the details to make Sidekick durable enough to stand up to the world’s top racers. A steel axle ensures the hub is stiff enough and strong enough for World Cup DH abuse, and a captive thread endcap system allows for tool-free cleaning and maintenance. The ratchet ring is replaceable along with all parts for serviceability.

At 452g for a Boost hub, the Sidekick hub is on the heavier side, but it’s likely less added weight than the extra chain and pulley to create a high-pivot frame design. J-Bend hubs will be available to build into your own wheelset, or e*thirteen will offer complete builds with their new Grappler Flux and Sylvan rims as well.

Hubs and wheelsets will be offered in all modern sizes and freehubs to fit most bikes and drivetrains.

Sidekick Hub Specs

  • Driver: XD, Microspline, HG, mini-HG, 7-speed integrated cassette
  • Size: Boost, Super Boost, 157x12mm, 148mm DH 
  • Axle Material: Steel 
  • Spoke count: Boost, Super Boost 28h, 32h / 157x12mm, 148mm DH 32H 
  • Spoke type: J-Bend
  • Bearings: 6903 / 6808
  • Engagement: 12° / 15° / 18° Adjustable Deadband
  • Material: AL 6061-T6
  • Weight: Boost (XD) 452g / Super Boost (XD) 450g / 157x12mm (7-speed) 652g / 148mm DH (mini-HG) 459g
  • Color: Black/Sterling Silver
  • MSRP: 499.95 $/€ (UK £469.95), 589.95 $/€ w 7-speed integrated cassette (UK £559.95)

New Rims and Wheels

It wasn’t enough to just have a revolutionary new hub system, e*thirteen wanted to offer the whole package as well. That’s where the new Grappler Flux and Sylvan rims come in.

The Grappler Flux rims are designed for “huck-proof durability” while the Sylvan rims are designed for aggressive trail, All-Mountain, and light e-bikes.

Grappler Flux Rims and Wheels

Grappler Flux Features

  • Low-profile designs: 17.5mm height Enduro carbon, alloy, and DH alloy / 20mm height DH carbon
  • 30mm Inner Width: Provides exceptional lateral stability while optimizing modern tire profiles
  • Available in high-modulus carbon or welded 6069-AL constructions
  • Optimized Carbon Layups: Specifically designed for DH and EN rims to balance durability, weight, and exceptional compliance
  • Hookless Flanges: Offer set-and-forget tubeless security and resistance to impact damage

Grappler Flux Benefits

  • Engineered compliance reduces impact forces and vibration, enhancing comfort and reducing rider fatigue
  • Tuned compliance improves traction and tracking and reduces wheel deflection in rough terrain, without compromising a high-performance ride feel
  • The same legendary toughness of our World Cup LG1 and Grappler rims
  • Lifetime free replacement policy on carbon rims / 5-year crash replacement on alloy
  • Suitable for both mountain and class-1 e-bike use

Grappler Flux Sidekick Enduro Wheel Tech

  • Weight Carbon: Front 900g / Rear 1160g 27.5”, 1200g 29” (Boost, XD) 
  • Weight Aluminum:  Front 906g / Rear 1187g 27.5”, 1206g 29” (Boost, XD) 
  • Spokes/Nipples: Sapim D-Light / Secure Lock Alloy  / 28H/28H – F/R
  • Rear Config: Sidekick Boost 148×12 / Super Boost 157×12  – Steel Axle 
  • Front Config: Sidekick Boost 110x15mm 
  • Driver: XD / Microspline (HG Avail.) 
  • Valves: Quick Fill Presta Tubeless Valves
  • Sizes: 29” Front, Rear 27.5”/29” 
  • Grappler Sidekick Flux Carbon MSRP: Front 799.95 $/€ – Rear 1199.95 $/€ (UK F/R £729.95/£1099.95)
  • Grappler Sidekick Flux Aluminum MSRP: Front 379.95 $/€ – Rear 649.95 $/€ (UK F/R £349.95/£589.95)

Grappler Flux Enduro Rim Tech

  • WeightAluminum 587g-586g / Carbon 560g-580g (27.5”-29”)
  • Wheel Size: 27.5” / 29” 
  • Inner Width: 30mm 
  • Spoke Count: 28H / 32H 
  • Valve Hole: Presta
  • Joint: Aluminum-Welded 
  • Bead Type: Hookless
  • Material: 6069-AL / High-Modulus Carbon
  • MSRP: Aluminum 129.95 $/€ (UK £119.95)/ Carbon 539.95 $/€ (UK £489.95)

Grappler Flux DH Wheel Tech

  • Weight Carbon: Front 1000g / Rear 1170g 27.5”, 1210g 29” (157×12, mini-HG) / 7-speed cassette +180g
  • Weight Aluminum: Front 1009g / Rear 1177g 27.5”, 1219g 29” (157×12, mini-HG) / 7-speed cassette +180g
  • Spokes/Nipples: Sapim D-Light / Secure Lock Alloy / 28H F, 32H R
  • Rear Config: Sidekick 157x12mm / 148mm DH – Steel Axle 
  • Front Config: Sidekick Boost 110x20mm 
  • Driver: 7-speed Integrated Cassette / mini-HG 
  • Valves: Quick Fill Presta Tubeless Valves
  • Sizes: 29” Front, Rear 27.5”/29” 
  • Grappler Sidekick Flux Carbon MSRP: Front 849.95 $/€ – Rear 1349.95-1499.95 $/€ (UK F/R £769.95/£1249.95-£1389.95)
  • Grappler Sidekick Flux Aluminum MSRP: Front 379.95 $/€ – Rear 659.95-799.95 $/€ (UK F/R £349.95 / £599.95-£699.95)

Grappler Flux DH Rim Tech

  • WeightAluminum 587g-609g / Carbon 580g-600g (27.5”-29”)
  • Wheel Size: 27.5” / 29” 
  • Inner Width: 30mm 
  • Spoke Count: 28H / 32H 
  • Valve Hole: Presta
  • Joint: Aluminum-Welded 
  • Bead Type: Hookless
  • Material: 6069-AL / High-Modulus Carbon
  • MSRP: Aluminum 129.95 $/€ (UK £119.95) / Carbon 569.95 $/€ (UK £519.95)

Sylvan Race Rims and Wheels

Sylvan Race Carbon Rims

  • Constructed from high-modulus carbon fiber with a 23mm profile height and a decade-honed custom layup
  • Include a clever valve dock for improved tubeless sealing on asymmetric rims
  • Weighing just 450g (29”), impact strength was tested at 7x previous TRS race carbon rims
  • Backed by a lifetime free rim replacement warranty

Sylvan Race Alloy Rims

  • 6069-AL construction, featuring welded joints and angle-drilled spoke holes
  • Low profile 20mm sectional height for exceptional compliance
  • Weighing in at 567g (29”), they show nearly a 4x improvement in impact strength over former TRS Plus rims
  • Dramatically improve ride feel and control
  • Backed by a 5-year crash replacement policy

Sylvan Sidekick Wheel Tech

  • Weight Carbon (29”): 800g/1060g (Boost, XD Driver)
  • Weight Alloy (29”): 920g / 1180g  F/R (Boost, XD Driver)
  • Spokes: Sapim D-Light 28H/28H – F/R 
  • Rear Config: Sidekick 148×12 Boost or 157×12 Super Boost – Steel Axle 
  • Front Config: Sidekick SL 110×15 Boost
  • Driver: XD / Microspline (HG Avail.)
  • Valves: Quick Fill Presta Tubeless Valves 
  • Sizes:  29” Front – 27.5”/29” Rear
  • MSRP Carbon: Front 779.95 $/€ (UK £709.95) – Rear 1119.95 $/€ (UK £1019.95
  • MSRP Aluminum:: Front 379.95 $/€ (UK £349.95) – Rear 629.95 $/€ (UK £569.95)
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25 Comments
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Duzzi
Duzzi
1 month ago

All was good until we came to the weight … almost twice as much as DT Boost hub, It is a downhill only product.

Angstrom
Angstrom
1 month ago
Reply to  Duzzi

The weight of a cup of water for better suspension performance and silence? I suspect a lot of folks would be willing to make that tradeoff.

StephenM
StephenM
1 month ago
Reply to  Angstrom

Except that the weight of a cup of water at the end of the swingarm (unsprung weight) will have a negative effect on the suspension.

Billyshoo
Billyshoo
1 month ago
Reply to  Angstrom

I would if ONLY for silence!!

tertius_decimus
tertius_decimus
1 month ago

Now, THAT is what I call innovation. No sarcasm here. Kudos to e13 and let’s hope they’ll improve on the design and let’s also hope it’ll be successful on the market.

Tim
Tim
1 month ago

Please correct the units. Sample rate is measured in Hz, which is samples/second. Hz/second is not a meaningful unit.

Anonymous
Anonymous
1 month ago
Reply to  Tim

Hz/second is acceleration of frequency (samples/s^2), which makes it in fact, meaningful, but wrong.

Jason
Jason
1 month ago

Is their travel range graph made up? How is it possible that the sidekick hub spends more time in every travel range? Did they just test the sidekick hubs for a longer period?

HDManitoba
HDManitoba
1 month ago

High pivot bikes would still need an idler pulley to prevent inchworm (too much anti -squat) effect when pedaling, right? Or it would lock out the suspension when pedaling and the hub is engaged. It can’t just magically un-engage when you’re pedaling just because it hits a bump.

Maybe I am missing something?

18 or 36 tooth dt ratchet ring seems like a much simpler solution that gets you most of what this does.

That said, silent freewheeling is lovely.

Greg
Greg
1 month ago
Reply to  HDManitoba

You’re correct that under power, nothing is changed. The suspension performance while pedaling is going to be entirely dependent on the bike you’re riding.

Regarding a low engagement hub: You can’t get the same effect with a low-engagement hub because the delay before the pedals engage varies unpredictably—it can be anywhere from zero to the maximum gap between engagement points.

The Sidekick hub, however, adds a fixed and consistent amount of delay (deadband) before engagement, providing a predictable feel that isn’t possible with a hub that simply has fewer engagement points.

HDManitoba
HDManitoba
1 month ago
Reply to  Greg

So it’s effectively the same as an o-chain except a tiny amount of spring force in the o-chain and it adds more complexity in a higher stressed area and more unsprung weight?

Having seen the lack of proper suspension setup among most riders, even good riders, I think there may be bigger fish to fry before this is a needed technology.

Seems like the low friction and drag would be more beneficial or sellable to the roadie’s who buy ceramic derailleur pulleys, but the weight isn’t going to be popular with the weenie side of that crowd. MTB’ers obviously haven’t cared about friction considering the proliferation of high pivot idler bikes. Of course you gotta have something new to market to the lemmings.

I still like the idea of silent freewheeling.

Greg
Greg
1 month ago
Reply to  HDManitoba

“You’re right that the O-chain has a spring to resist chain growth, while in the Sidekick system, the only spring is in the derailleur cage. The key difference is that with pedal kickback, the O-chain can only reduce the effect when it happens, but the Sidekick hub prevents most of those events from happening at all.

Another unexpected benefit is how allowing the cassette to move freely helps calm chain vibration—it makes the entire drivetrain feel smoother and quieter. And yes, the silent coasting is pretty great. Hearing your tires on the dirt is kind of a revelation in terms of reading the traction available!

Full disclosure: I work at the company, so of course I’m partial to this system!

will
will
1 month ago
Reply to  HDManitoba

i dunno why people like silent free wheels. you can overgrease most freehubs and itll be silent and work fine you know that right?

in this case its only quieter due to less engagements – the only interesting bit is, indeed, the delay it adds.

FritzP
FritzP
1 month ago
Reply to  will

The 3 drive pawls disengage completely and the other pawl is only lightly sprung. Overgreasing only works for a while and can impede engagement, especially in the cold. I had an i9 hydra for a short while. Overgreasing only made it slightly less noisy for about a half hour of riding then it was back to BUZZZZZZZZZZ.:( I’ve also ridden the Shimano rear hub which was nearly silent and the difference is very apparent. Hearing the tire/soil engagement is great.

HDManitoba
HDManitoba
1 month ago
Reply to  will

Because the buzzing is annoying. Grease only lasts so long and has other problems as someone else mentioned.

It’s worse on road and gravel bikes because I feel like you coast more.

One of the beautiful things about bikes is the silence. Sucks when someone else is riding around with a speaker blasting music or riding an i9 hub. There’s enough noise pollution all the other parts of my day.

JNH
JNH
1 month ago

Call me stupid, but what advantage does this offer over running a 24pt hub for 15 degrees of float when coasting? Unless you have a bike with a truly wacky suspension arc the hub won’t catch the ratchet unless you pedal.

Veganpotter
Veganpotter
1 month ago

Not remotely cool enough to need this but it’s awesome

edge
edge
1 month ago

eThirteen: Hay we have the most ratchet splines for super quick engagement!!!!!!
Aso eThirteen: “Hey look at us!! We have the solution for too many ratchet splines!!!

Sergey
Sergey
1 month ago

Imagine an uphill on enduro bike with 28T at front and 52T at back – pretty common in mountains, right?
But with this hub’s 18 degrees of free stroke at the hub it will translate to 33!!! degrees of free stroke at cranks. Of course I am picking the extreme, but to prove a point – this system is very gear dependant. o-chain on the other hand is not.

Last edited 1 month ago by Sergey
seraph
seraph
1 month ago
Reply to  Sergey

So what you’re saying is that I should run this hub AND and O-Chain?

Sergey
Sergey
1 month ago
Reply to  seraph

no, my point is that ochain will give you consistent free angle at pedals, e13 will highly depend on a gear. 28/52 at 18 degree setting will give you 33 degree of engagement at pedals. 28/10 at the same 18 degree setting will give you 6.4 degrees at pedals. 33 to 6.4 discrepancy on 10-52 cassette.
If you set e13 hub right for your downhill range of gears – it will be too much of a free stroke for uphills, or vice versa

Last edited 1 month ago by Sergey
HDManitoba
HDManitoba
1 month ago
Reply to  Sergey

Good point, though on an uphill you are less likely to allow the chain to go slack and un-engage the hub ratchets.

But for pedaling, the springs in an o-chain could work as an advantage because it may stay pulling chain before it hits the hard limit and start to engage hub earlier.

Motorcycles have cush drives. Mostly street bikes but they prevent snapping chains and help keep traction by not suddenly applying all torque instantaneously to the wheel and tire.

Sergey
Sergey
1 month ago
Reply to  HDManitoba

“You are less likely to allow the chain to go slack and un-engage the hub ratchets” only if the uphill is smooth, like a fireroad. Technical climbs often demand to adjust crank position before a steep ledge or any sort of step, I don’t know how to say it correctly.
So this system basically makes more freestroke at the cranks in lower gears, where we need faster engagement (alright, only on technical climbs, but still), and less freestroke at higher gears, where it could be beneficial for lowering the pedalkick on downhills.

HDManitoba
HDManitoba
1 month ago
Reply to  Sergey

Good points.

andy
andy
1 month ago

so doesn’t this have more slack when starting to pedal???

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