After spending a few hours on Zwift this weekend I decided to bite the bullet and build a DIY rocker plate. I have reviewed all of the models available for purchase that I could find, and they all seem crazy expensive for what they are. And I’ll need 2 for my house which makes the effort a little more worthwhile.
I’m planning on using a linear motion system to provide the pivot for side-to-side motion and the bearings for front-to back motion. I’m trying to follow the design by Andrew Grabbs We Ride South DIY Rocker Plate Plans
Finding a ~1400mm linear rod (at a reasonable price) has proven to be tricky but I found a great source for a 1000mm guide rail set at VEVOR Linear Guide Rail Set, SFC20 1000mm
I’m planning on either using a single 1000mm rail if I can make that work, or more likely cutting the rail down and using 2 for each rocker.
I’m a little worried about getting the alignment of the rails correct though. Apparently the tolerances will be tight and it can be tricky to get the rails perfect.
The last component that I need is a set of springs to limit the front/back movement. I haven’t dug around yet but the design calls for a 5" spring with an outside diameter of 1" that provides a compression force of ~100 N.
Does anyone have any ideas for a local source? I’m hoping to finish this over the holidays as a DIY project with my son Sagan.
If anyone is interested in building one please let me know and I’d be happy to share knowledge and plans.
I would love a rocker plate. I can’t handle more than 2 hours on the trainer. Your plan looks really cool. I have seen quite a few (actually tons recently) on facebook about people using those little balance pods as a substitute for a rocker plate and also a lot cheaper. They all seem to like them except the one guy whose trainer came off one in a sprint. It’s hard to tell whether these are real opinions or just internet people wanting people to do crazy things. I have balance pods but have not tried them with the trainer
I’m actually going to try with just using the balance pods first (possibly as early as today). But after researching more my conclusion was that they are pretty unstable and make the ride feel bouncy. Although better than nothing at least for trainers that are very rigid.
Apparently a big improvement is just to mount 4 pods between two pieces of plywood with a hole cut to access the pump holes in the pods.
Just watched the first video. Seems fairly simple. But, wondered what the weight limit would be for us 200+lbs Clydesdales.
I know a few who have done the DIY rocker plate thing. @Orrin has one.
I have a Kickr CLIMB which helps in Zwift. It lets you know immediately when a climb starts as it adjusts up. The rollers in Sand and Sequoa’s feel like a roller coaster. That somehow makes it more real. And a vastly different position on the bike when you hit that 17% gradient on the Zwift KOM. My head almost hits the ceiling. Wonder how that could be anchored onto the board?
All that said, I predict this to be a popular thread @KevinGoertz . With offers of cash for you to build one for me !!! Or invite me to the garage and we can do an assemble line build.
Scott Brubacher has built a good one that I’m assuming he is using himself. But maybe he’s open to building another one. I built and still use one of these rocket plates. Pretty easy to build https://youtu.be/WIOElZ-9gLQ
Thanks Alain. I’d also be willing to offer cash for someone else to build
If my prototype goes well I’d be happy to setup an assembly line. Some of the major effort will be designing and cutting the first plate. But once that is done we’d have a template to quickly cut others. And I have a can of textured wood paint (in grey) that should work really well but it takes a long time to dry. Doing a few at a time might be useful Rez Revitalize Advanced Wood & Concrete Resurfacer Paint
@WillA are you interested in a neighbourhood project?
If anyone already has a good template for the plywood plate it would be really helpful!
I’m certainly interested and happy to help out. We might need different plans for different trainers / use cases. Folk with a kickr climb will need a front support that those with a static front may not need. From the reading I have done, different trainers have their legs in different places and need the support in different places as well as the tie downs in different spots e.g. https://omnirocker.com/
I’m actually running a Kickr Bike so might need a very different set of ties downs than most people
I will say 1000mm linear rails aren’t long enough. I built it using them and the front was bending. I brought a second rail and cut it, that was a real pita and needed an angle grinder. I used a drywall square to line up the bolts for the second rod when I added it, and alignment wasn’t too difficult.
The hard part of the build is lining up the bolt holes, mines not perfect and is missing one or two but is holding up for now. I did half of it in the dark when drinking, so that may have been a factor.
Sprinting is different but given that I don’t like sprinting its a non issue for me. it does bounce and move a lot under out of the sadle efforts. The kid makes it move pretty violently but that is probably a challenge he sets himself.
In terms of riding comfort it is night and day for me. I don’t want to admit to riding the trainer for 90 minutes the other day but it happened I got off the trainer without any real discomfort and could have gone longer, in the past I was done at 60.
Thanks Rob. I saw one of your videos with Devin riding…the trainer was definitely rocking
Thanks for the source on the springs! I’ve been trying to find something appropriate but haven’t had any luck yet. I’ll order those from Grainger.
I thought the 1000mm rails (alone) would be a long shot but you’ve confirmed it. I wonder if the 1000mm rail plus a 500mm rail would work to avoid having to make more than 1 cut. I couldn’t find a longer rail without paying an extra ~$100 in shipping.
I was planning on cutting the rails and was hoping that a hacksaw would be enough. But it sounds like I might need to go the power route. Ouch. I assume that is because the rails are carbon steel.
I’m also a little worried about alignment of the bolts so I hope it isn’t too tricky.
I tried just using the hedgehog balls on a piece of plywood this evening to see what it would be like. It was nice to have the additional side motion, but it was very bouncy and the fore/aft motion was too much. Definitely better than no rocker plate, but I do think it will be worth at least having a hinge/pivot instead of just the balls.
Which balls did you use for cushioning? Did you cut out a track in the plywood to allow the balls to roll?
I started with a hacksaw and gave up nearly instantly.
I’m wondering if two 600mm rails might work and if that could be sourced, you basically need the trainer supported and the front.
As for the balls I used
I cut a track on the bottom so they didn’t pop out and sanded the edge well. being inflatable you have some control on how much the plate rocks. More importantly its easier to level the trainer, even a small out of balance position and your body will correct it, this seemed to cause muscle fatigue on one side as you counter lean sub consciously.
Your kids are way past the point of intentionally moving a rocker plate for the fun of it, but it would be interesting to see how someone with there power would move the plate.
Just to update. I’ve been riding this week with a temporary rocker plate. Four of the small hedgehog exercise (half) balls secured on a piece of plywood underneath our trainer. The results are very mixed, The extra side-to-side movement definitely reduces fatigue a little especially on my back and hips.
But the fore-aft movement is too significant and the bike moves forward and back with each pedal stroke. Not good. Plus it feels really bouncy especially when standing or at high cadence. Also not good.
As a result I have also concluded that just strapping the small exercise domes under the trainer wouldn’t work well either.
Since I have already bought all of the parts I’m going to continue with the vertical motion bar which acts both as a hinge as well as spring-loaded fore-aft movement. Although I’m not convinced yet that the fore-aft motion is going to be that beneficial. Using the vibration isolation mounts as a hinge would be simpler and probably give most of the benefit.
I’m hoping to cut the rocker plates from plywood over the next week. After the first set it would be easy to use them as templates for additional sets. I’ll add a picture when complete just in case anyone wants to cut a similar rocker plate. And I can post my full parts list including links and prices.
I finished building two rocker planes for my family this weekend. It took a full two days even with the significant help of my son Sagan. He did a great job and I enjoyed working on the project together.
I decided to document all of the parts I used and detailed steps to recreate with the hope that it might help others create their own. If anyone has any suggestions or corrections please let me know and I will update.
I haven’t gone for a long ride yet, but Sagan said it worked great and made the ride much more natural and comfortable.
A direct (read only) link to my Google doc his here.