I’m a big fan of rocker plates–those platforms you place beneath your trainer which allow your bike and trainer to tilt side to side. I’ve used various plates for over four years now, logging over 20,000 Zwift miles atop a rocking platform of some kind.
But there’s one thing that really bugs me about some (or even most) rocker plate setups I see, and it’s time to get it off my chest.
This issue isn’t confined to the DIY rocker plate crowd, although I’ve seen it there. And it’s not just a problem for cycling newbies–I’ve watched many expert cyclists make the same mistake.
So what’s the problem? The rocker plates are too tight, often leading to poor rocking form.
What does that mean, exactly? Well, “tightness” in this context refers to how much force it takes to move your bike from side to side. Next time you ride outside, pay attention to how easy and far your handlebars swing when you’re out of the saddle climbing or sprinting. Chances are they’re moving 4-6 inches side to side, without much effort.
Now watch this CyclingTips video where James is trying out the Saris MP1 rocker plate. (I’ve started the video at 6:24, where James is using the MP1):
Notice how small the range of motion is? That’s because the MP1’s leveling springs are very tight.
Tight vs Loose
Are tight springs always worse than loose springs? Not necessarily–there are plusses and minuses for each setup. I chatted with rocker plate wizard Chad McNeese about this, and we came up with a list of pros and cons for tight vs loose springs:
Tight Springs
- Pro: feels more stable, which is nice for new users
- Pro: more comfortable than a typical rigid trainer setup (even a bit of movement makes a big difference)
- Pro: reduces frame stress created by typical rigid trainer setup
- Con: usually results in incorrect bike lean/pedal timing (more on this below)
Loose Springs
- Pro: increased range of motion allows a more realistic feel
- Pro: more comfortable than a typical rigid trainer setup
- Pro: reduces frame stress even more than a tight spring setup
- Con: less stable, requiring more body engagement/rider attention
In summary: new rocker plate users will probably feel more comfortable on a tighter setup, because that little bit of movement takes some getting used to when you’ve been training on a rigid setup. But once you’re used to the motion, chances are you will want to loosen it so you can get full, natural motion out of the saddle.
Bass Ackwards
By far the biggest problem with an overly-tight setup is that it leads riders to adopt terribly incorrect out of the saddle form.
Look at this shot of Peter Sagan winning the 2017 Grand Prix Cycliste de Québec. Note the out of the saddle sprint form of all these pro riders: specifically, that the bike is leaning away from the leg that has the pedal down.
This is proper, natural pedaling form– pulling on the handlebars and leaning the bike add power to the downstroke, as the lean is effectively pulling the pedal up while your leg is pushing the pedal down. And as you lean the bike one way, your body counteracts that lean with its weight in the other direction so you stay balanced.
In fact, it can’t work any other way outside–if the bike was leaning in the same direction as your body and down leg, you would fall over!
GPLama Shane Miller talks about this very problem is his “Round 2 Rockit Launcher” video (below). Around the 2:50 mark he says, “Every video we’ve seen of people out of the saddle on a rocker plate looks like this.” And he’s not wrong–I’ve seen so many bad videos.
But it is possible to have proper out of the saddle form indoors. Here’s a quick demo video I shot which demonstrates basic, proper form out of the saddle on a rocker plate–both climbing and sprinting:
Now compare my form to what I saw at the Saris booth during Eurobike 2019. (Keep in mind this was an experienced, paid rider–and the other booth rider was exhibiting the same form!)
Saris isn’t the only one who can’t seem to market their own product well. Even SBR, whose rocker plate I really love, displays a demo video on their homepage showing this backward form:
Tight rocker plates lend themselves to this poor form because the rider is forced to use their own body weight to lean the bike over.
Proper technique has the bike swinging side to side quite freely while the body stays upright, counterbalancing the tilting bike. But a tight plate requires the body to lean right in order to tilt the bike right, then lean left to tilt the bike left.
Best of Both Worlds
So what’s the solution to this rocking quandary?
Adjustable tightness, and awareness of proper form. That’s it!
Most rocker plates use some form of adjustable spring: the SBR ROCKR uses inflatable rubber balls (less air for a looser feel), as does the CoPlate. Chad McNeese’s DIY Rockit Launcher uses foam blocks that can be swapped out to vary the tightness.
Some very simple “single platform” rocker plate designs such as the Axxion Rocker Plate aren’t adjustable since they have no “moving parts”. And the most notable exception to the adjustable norm is the Saris MP1, which costs around twice as much as the SBR ROCKR and CoPlate without allowing adjustment. Ouch.
(I don’t want to bag on Saris too much: the MP1’s build quality is rock solid, and it allows significant fore-aft movement, which the other rocker plates do not. But the spring’s tightness combined with a lack of adjustability is a deal killer for me.)
Embrace the Process
Once you have a plate with variable tightness, set it where you’re comfortable, while being careful to maintain proper out of the saddle form.
Note that if you’ve done a lot of riding on a rigid indoor setup, it may take some hours of riding to adjust your form before you feel comfortable on a rocker plate. This isn’t a bad thing – you’re unlearning unnatural indoor habits and returning to more natural motion.
If you can’t lean your bike to one side without also leaning your body to that side, your setup is too tight. Loosen it up, get used to the feeling of having your core more engaged and your bike a little more free-floating… and enjoy it!
Rock on.
Your Thoughts
Are rocker plates inherently flawed? Just a passing fancy? Or perhaps victims of their own poor marketing? Share your thoughts below!
Nice article, profound research and testing! We shared already the same experience reg the MP1 from Eurobike test rides.
But you forgot to mention the SprintBoard (available in Germany/Euroe) in your list of DIY Rocker Plates 😉
👍🏼 Eric
Hi Ruediger,
I didn’t know about the SprintBoard! Looks like a great solution, basically identical to the SBR ROCKR which is a solid unit.
What about turning the bars? Should that be a factor? In most of the the screen shots form riding on the road, the front and rear wheel are on different planes.
I think that’s a very small part of the realistic out of the saddle feel, although it is there for sure. Sort of like adding forward-backward movement, I don’t think it’s worth what it would take to replicate it inside, when you can get 90% of the out of the saddle experience with a simple rocker plate. My two cents!
I would absolutely have to have turning involved. It drives me nuts having to spend 30 seconds getting my bars straight again after a hard sprint. I wouldn’t pay for it to be part of a branded rocker experience, though, unless it allowed me to mount the bike physically lower on the whole board to get closer to a realistic side-to-side pivot axis.
Over the past 3 years I’ve built three iterations of a rocker now using 2 inflatable balls and isolation mounts for rocking, dampening and adjustment (no moving parts), but I’ve added steering with a cheap lazy Susan from Lowes, with spring return for self centering. A very simple modification that really does make the bike feel much more like IRL for climbs, sprinting and just generally riding around. It would be an easy DIY mod for most of the commercial rockers.
BTW, the front wheel center of rotation is not at the tire’s contact point – it’s about 4″ in front of the contact point. Elite figured this out for their Sterzo.
I made my own rocker for my Hammer trainer. I use 10″ wheelbarrow tire inner tubes for suspension. After some testing with air pressure, I can now swing the bike side to side to the point where I could go over. The tubes might seem like a crude form of suspension, but the ease of raising/ lowering pressure to your liking works.
I was in early on with the SBR rockr and have a few working models including a unit with VERY little centering force and ~4″ of fore/aft movement. It’s great for non race rides; but found out when tired, hypoxic and form breaks down it, it was dizzying to be “out of sync”. It also required constant tinkering to keep balanced(I’m sure this could be be worked out… I prefer the low center force with little to no fore aft currently
After reading GP Lamavs blog re rocker plates and DIY. I also built my own. 3ft Square piece of 25mm thick mdf. Screwed 15mm gas pipe clips along centre line, clipped in copper gas pipe. Inserted thick steel threaded bar into copper pipe leaving it sticking out both ends. Got 2 thick timbers and drilled a hole through and inserted threaded bar with washers either side of timber. Bolted all together n screwed thick timbers to a old large desk top. (whick is longer than bike) Mdf board rocks easily both side to side. Elite Drivo trainer added to mdf… Read more »
Quick question. I have an MP1 on pre-order but after reading your impressions I’m wondering if I should have saved money and stuck with the Sbr rocker. Is the lack of side to side adjustability really a deal breaker? The increased fore aft movement seems kind of meh to me.
I’ll say this, Michael: I’ve used them both. And I would pay much less for the MP1 than for an SBR ROCKR. As I said–the lack of adjustability is a deal breaker, because you simply can’t get natural out of the saddle form with a tight rocker plate.
I’m not sure how you’ll get an accurate road feel without the pivot point being at the point the wheel contacts the road rather than several CM below, in the case of the rocker plate or from the axle in the case of the Neo. That’s just the start though because the typical flywheels only handle the inertia side of things and not the gyroscopic affect of a spinning wheel, the affect of which will be vastly different according to the speed that it’s spinning.
I live just a few miles from SBR. I drove to pick up my ROCKR PRO last fall. Love it but it seems to sap power while sprinting (Sprintapalooza!). I jam two wedges of firm foam under the widest points to minimize rock. For normal group and climby rides, pull the foam out and go. #DIRT
I researched both and ordered the SBR unit. Spoke with folks at the company and they were great about answering my questions. When I called Saris they couldn’t even tell me when the product would actually be available. Given the huge price difference this turned into an easy decision.
We resisted for ages, with a Tacx Neo we had some hinge flex built in anyhow. But after listening to others extol their virtues, we sunk an investment into https://turborocks.co, its not cheap but we have never looked back (700 hours already sunk on fixed). It users air tubes and elastomers, so allows the rock to be fully tuned to suit your style. Want more rock, set psi lower, want it firmer add psi. Love the high quality design but more importantly how does i help? We have found for racing and endurance work it teaches you to pedal smooth,… Read more »
4-5psi [edit}
Hi, I’ve just ordered the turbo rocks plate, have you found you can get the correct form as discussed in the article? (Rocking against the down going leg) I did notice that Turbo Rocks also talk about how the lean is opposite to outdoors with their product which again seems poor sales technique if it can be avoided?? It also seems like rocking with bad form is only going to lose power as some of the pedal force is wasted pushing the bike in the wrong way…… Looking forward to trying it for myself anyway!
That is the EXACT reason I haven’t gone down the rocker path. In fact, I’d venture to say the pivot should probably be about 5 – 10 mm ABOVE the wheel-contact point, as most of us don’t actually sprint in a truly straight line.
I’ve been using a Kinetic Rock N Roll set-up with a front wheel turntable for 2 years now and I think it’s as close to ‘real world’ as you can get (on my budget). I know that my set-up is a wheel-on style but that’s a whole other debate in itself but having the ability to rock AND turn the bars as I do makes the push, wether out of the saddle climbing or sprinting, much more ‘real’ to me.
You make the point that a tighter setup requires leaning your body to get the bike to move, which is not natural or intuitive. Softening the spring may require less effort to get the bike to move, but it’s still not natural or intuitive. That is why so many people lean the wrong way on rockers. Unless the rider can control the tilt-motion without using their weight to do it, rockers will always require a special technique and good timing.
I disagree. Have you ridden a loose rocker plate, Leroy?
The way I have mine set up feels quite natural and intuitive. There is very little “centering force”, so tilting the bike is as easy as… well, tilting a bike!
I just got a SBR. Roughly how many psi is your setup?
Basically zero! Both of the rubber balls are half inflated.
Right folks, 26 inch mtb tube all the way round the plate.In the middle a half pipe the width and height of a mtb bike tyre. This is the rocking part. Because of the weight i wouldn,t go any smaller. Inflate for resistance.As for sprinting watch track riders, i don,t agree with all of the wright up about sprinting looks like the so called experts and experienced people still have a lot to learn although some of them are on the right track .Right thats me finished with a small rant keep on zwifting and have fun.
Without the rotational mass of the wheels to push and pull against, a rider is just wasting energy and training awkwardly…regardless of getting it to look right, the physics are wrong. There is no doubt that the rocker plates have the added benefit of protecting the frame, but that only takes a sight movement to do this. The vast benefit of movement trainer and the rocker plates is the more natural movement when you tail is in the saddle. The movement takes a great deal of pressure off your bum, fore/aft in a straight movement and side to side in… Read more »
Agree – I built my own rocker last year with some plywood, a 4″ ABS pipe as the fulcrum, and closed-foam blocks as springs. The amount of movement it adds vs. being nailed to the floor has transformed the indoor riding experience for me. I’m not expecting it to mimic the feel of an outdoor ride – just make it “better enough”. Maybe a looser setup would help me keep my core fitness a bit more – I find in the Spring when I’m back out on the road my upper body is always out of shape. But I’m happy… Read more »
The MP1 is adjustable, not having my hands on one…how loose can they get?
It’s not adjustable.
Eric, TurboRocks manufacture a quality product in the UK, The Realplate+ with hundreds being sold throughout Europe & the US. Great feedback & reviews. One is also being ridden by Marco Marcato of Team UAE along with Amateur & Neo Pro Teams here and across the water. Would be great to be included next time. All the best & keep safe, Steve
Does anyone have experience with the Axxion rocker? Looks interesting.
https://m.youtube.com/watch?v=kPZKsACtGMg
Hi Bill, I have sent one to Eric for him to evaluate! I hope he reports here soon. Regards, Max McAllister
Eric, any thoughts you can share regarding the Axxion rocker? Thanks!
I’ll be posting a review soon.
I’ve been riding my Axxion for a couple of months now, after looking at the options it looked like the right one for me. It’s movement is essentially unrestrained (imagine a sideways rocking chair) and gives me a really free feel. I am not much of a sprinter but wanted the movement for comfort which it definitely delivers.
Eric having just built my own without the restriction of pivot placement because I own a neo my pivot is above the deck thus the plate actually swings rather than pivoting mimicking the true pivot point of a normal bike and also naturally self centres and requires Less spring tension that means it’s stable when in saddle and loosens when out of saddle
What a lot of people don’t realize is that when you are out of the saddle, only the bike should move side to side. The body don’t move (its more logical that 7kgs move and 70kgs don’t !). With a very loose rocker plate, you can do exactly the same. Your bike move as freely as in IRL. I love to climb out of the saddle and discovering rocker plates last month (just before the lockdown in France) completely change my experience: today we had the authorization to practice cycling again and I had exactly the same feeling outside on… Read more »
For me it’s not about proper leaning; it’s about the massive improvement in comfort. The little bit of side to side and front/back motion I get from my MP1 make it easier to ride longer on the trainer. I spend an hour or two each week in the winter on rollers before I switch to the smart trainer. I’m lucky to have space for both.
Are any rocker plates large enough for the Tacx Neo Bike or the Wahoo Bike?
I rolled my own rocker plate. The most important features for me were that it needed to be as compact as possible and support steering. It has a welded platform that just barely supports the tacx neo in the back. In the front I removed the front wheel and connected the fork directly to a Sterzo that is on a raised platform. The steering works but I have been wanting to connect it to the leaning of the bike but I haven’t committed to tearing apart the Sterzo to do that. The stiffness is adjustable by foam pad insert. I… Read more »
I built mine using pillow blocks, an axle and tennis balls for rebound, mostly use it because of back pain with the fixed trainer. Wonder if there is any any way to stiffen it up as the speed increase to mimic the gyro effect
I’ve been on a Kurt Kinetic Rock & Roll T-2300 for about three years. I have had no problem with rocking out-of-phase since day one. I feels completely natural to me and swapping back and forth between the my road bikes outdoors and the track bike on the trainer is easy. 30 seconds on either and it’s right back to feeling normal. Honestly, I don’t even notice being out-of-phase during a Zwift session. The added comfort of being on a rocking bike trumps the phase shift for me. BTW, the old Rock & Roll trainers and the new R1 offer… Read more »
I agree with Robert King and would add: It is interesting to see a review of rocker plates and understand their various characteristics. It is clear that there are very many cyclists who are constantly striving for the perfect set-up to mirror IRL in every respect. Many others, like me, are possibly just looking for a configuration that makes indoor cycling a more comfortable and enjoyable activity. The participation and motivation being key. I am an old guy and have pedalled thousands of kilometres on my wheel-on Kinetic Rock and Roll over the last 7+ years, the last 3.5 years… Read more »
I have been working on a design and refining it for almost 20 years, well before any commercial designs came out. I have this problem solved. My trainer has more engineering and expensive components than anyone could imagine. I have been using it on virtual group rides for about the same time, and it works and I get my upper body power into the peddles, much like a real sprint.
Eric, do you have any contact with the sbr rockr folks? I ordered over a month ago, the page says it takes 2.5 weeks to ship. I politely inquired twice now after 3 weeks and 4 weeks and have heard nothing back. Wondering if something has fallen through the cracks.
It’s been a while since I’ve been in touch with them, but I would just call their number if you want a quicker answer!
Phoned them shortly after your comment and left a polite message asking for an update, three days later and I haven’t heard a peep from them. I’m starting to get worried.
I ordered mine last week and it arrived yesterday…
Thanks for the info!
So that means there definitely is a problem with my order. I don’t know how to solve this, I’ve tried contacting them several times by all available means. Does anyone have a line of contact with the sbr rockr guys?
Update: I’ve finally heard back from someone at the company. Still waiting for my rockr plate to be shipped though.
What about balance [email protected]
I’ve tried a few of these designs and I honestly don’t think any of them get it right in terms of feel. All of them introduce some movement at the saddle to relieve numbness, but none replicate the swaying of the bike in normal motion, let alone sprinting or standing climbing.
For a while I used a big square of plywood with 35mm holes to locate half a dozen tennis balls which worked as well as much more complicated options.
Incidentally – anyone who’s watched Degenkolb sprint might think he learned to ride on a Wattbike!
I have an older Wahoo Kickr, prior to 2017 and the electronics problems. I noticed the Wahoo is selling a new Kickr foot kit called KICKRaxis action feet. It substitutes new foam based feet for the existing feet. Takes about 15 minutes to install. Advertises +- 5 degree side to side motion. I tried it this afternoon, and where my butt usually gets tired after about an hour, I road for 1 1/2 hours with no soreness, and stopped then because I had other things to do.
What’s different (new) in this article vs the older one?
Tweaks to the text throughout. Typically if I republish a post it’s after revising it to make sure information is current. I think the whole “embrace the process” section at the bottom is new, too.
I am happy with the MP1 so far. I got it a couple of days back. hooked it up with my Kickr Bike. You can achieve good form (needs a little will and concentration) even though I also hate the lack of adjustability. might try some hacking on the engineering and springs. Related but other question: I love the forward/backward swing of the MP1. the main reason got it… BUT – I feel I loose a couple of Watts on the Rocker Plate because energy is lost in “rocking”?. Especially on heavy climbs and sprints. is this something someone has… Read more »
Coming from a background riding rollers,, one of the things you lose when riding on a “smart” trainer is the effect the spinning wheels have on your stability. You can prove this to yourself easily. Coast down a street at 5 kph and try to balance with no hands, then do the same at 30 kph. Perhaps an ideal solution would be to have a very loose rocker setup, with a wheel-in trainer (which is what I have), and maybe something to spin your front wheels as well…. sort of like… rollers. Maybe I can use the the old “not… Read more »
I did a bunch of hill training last winter on my KCKR bike for early season races and it transferred to the road much better than I expected, except for the side-to-side motion when out of the saddle. Because I didn’t ride outside at all before the first race, I was caught by surprise on the first few climbs and kind of had to relearn that in a hurry. So I’m really interested in reproducing that motion this winter, and this article & discussion are very enlightening. I’m looking at the SBR pro DIY kit.
I totally agree with the problem you point out, but I am less convinced of the solution. Tons of videos showing people doing it wrong but I have yet to see one where someone tilts naturally on a rocker. It would be nice if there was a video where someone was able to fix this issue by lowering the pressure in their rubber balls (or whatever for their specific rocker) and show they were now able to rock “right.”