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Yep. Same idea. Some of the designs Iâ€™ve seen are pretty elaborate
Genius! The Facebook group is great as it has a wide range of solutions. Mine is just a pvc pipe down the center of my elite direto and some small inflatable bags under the outer legs. I donâ€™t know that a full on platform would do much better
I can say the standing efforts feel less harsh on the quads since you aren't stuck in an awkward position trying to pedal when the trainer is fixed.
Next up is to work on my saddle/position because I know I haven't found the right combo yet. Current setup is ok but I've really got to fiddle with the position and tilt more before trying a different saddle.
I ordered the DYI kit from SBR and found the board design on the Rockr Plate Facebook site. Actually created a template of the boards with holes pre-drilled and then transfered the template to the final boards so as not to make a mistake. 3/4 in. birch boards. Will probably coat the top with Truck bed liner paint or just some carpet/rubber matting.
The benefit of the DYI kit was all the HW was included, including the mounts for my Kickr. You could get it yourself and maybe save $50. I spent about $200 all in.
I thought I might lose some power on it, but that hasn't been the case at all. It is a little bit louder than before, but the carpet or coating should solve that part of it.
I had saddle sore issues going longer than an hour on my Hammer when I first got it. The rocker took care of that problem, and my longest indoor ride was 4 hours. Itâ€™s stull not going to feel as natural as rollers however, but the rocker does help a lot.
My thought is that what you need is a roll axis that goes through the contact patch of the rear tyre, and up through the handlebars or so at the front.
In practical implementation, you could make the trainer (at the rear) tilt at floor level. But the front needs to move differently. The easiest practical way I can see to achieve this is with a 4-bar linkage supporting the front axle, with the lower pivots slightly wider than the upper pivots.
I'll draw a picture if this doesn't make sense.
OK, I'll try, but I am mostly fluent in Engineer.
Imagine something like this thing:
But instead of mounting the fork in a rigid frame, replace those two vertical links with bars that have a hinge/pivot/balljoint at each end.
From front on, it would look like this:
The green would be the frame of my contraption, and the blue triangle is the (imaginary) lower portion of the front wheel (that you have removed).
I think that would make for a much more natural feel. If you tilted the linkages forward slightly from vertical it would also provide some simulation of steering effect.
And people pay how much for a Kickr Climb? (In fact this could be nicely integrated with one...)
Plus rocker plates are a crude simulation of real motion.
Option B would be to mount the front wheel on a roller (passive or electrically driven), so you can move it quite freely and completely naturally.
<royalty cheques to matty at mattyisafreakingenius dot com>
As you say, the problem with current rocker plates is the pivot point is too low. When you lean, the wheel slides side to side as well. I actually recorded myself riding up a hill over a line I drew with chalk to try to estimate how much motion there was. Based on my crappy video and some equally crappy math, I think the actually pivot point is somewhere around 3 inches above the ground, but this obviously depends on how much you're leaning, how hard you're pushing the pedals, etc.
I have two design ideas to deal with this but neither is 100% there, IMO. The first is the basic version, where you have a board that the bike and trainer sit on , and that board is attached to an outside frame. The board is attached to the frame with pillow block bearings on the frame and linear motion bearings on the board, with a short shaft front and back. I would include a compression spring over the shaft. This would allow a slight back and forth motion, raise the pivot point, and allow side-to-side rocking. It wouldn't allow for any "sliding" of the wheels, like you illustrate.
My more complicated design also involves the board for bike/trainer, and a frame. This time though, there would be a second bottom board, with the rocking motion between them, typical to how most designs are. I would use only pillow block bearings so it only rocks. I would then suspend the boards, attaching at the bottom board, to the frame. I thought about 4-point linkage (I notices my wife's glider ottoman uses that design) but I decided it would be limiting. I would just use a short steel cable, pulled out to the frame from the bottom board at perhaps a 35-45 degree angle. Gravity would bring the board back to the middle so no springs needed. This would allow side-to-side, front-to-back movement, including allowing the rear to move more than the front.
I haven't built either of these but I'm planning to build something soon.