Thanks!

Hi there. Interested in your lever design. Can you provide a youtube link showing it? Cameron

Those were the Nashbar rollers. I don’t think they are sold anymore. Maybe you can find some on ebay or Facebook marketplace.

timtak1, hundreds!

Thank you! I am strongly considering getting some.

It does produce some heat but not very much. Less than 100 degrees F.

@@whiterol and Nicolas: I think it's the same concept used in regenerative braking to produce electricity in electric car brakes (or the resverse there-of). I'm reading up on that now. Heat is the by-product, but aluminum, as a heat sink, disapates heat quickly - especially from rotating, so as Roland said, probably no different than riding on black tarmac on a hot day.

I made the brackets out of 12 in. L x 1 in. W x 1/4 in. D Perforated Steel Straps from Home Depot cut to the proper length in their tool rental department (be nice to the employees over there) and bent at an angle. Has worked well.

on my rollers I don't bother to figure out a way to prevent from falling off. Once you get used to riding you won't fall off. I am more concerned about having something for my front wheel to touch. . Generally speaking if you touch that roller wheel with your front wheel, you will likely counter steer to stay up and fall down - just as if someone in front of you in a paceline touches your front wheel (or you touch their back wheel with your front), you are going to go down. . .If you absolutely need a safety net like that, I'd put it on the back wheel area, not the front.

No, it has to be metal.

variable resistance: use an electromagnet. Then get the SDK from Zwift and control the power to the electromagnet from the Zwift output. ..might need to do a little programming, but if you know the concept of eddy currents shown here (passing the conductor - in this case the aluminum roller) through a magnetic field, creates a magnetic brake), then you probably can program what you need to increase or decrease the power to the electromagnet based on the zwift output/input. When you do that let me know because I'm not a programmer, but I bet I could learn. Also might need to use Arduino or Raspberry Pi to create the controller, but again, someone with more brains than me can figure it out and let me know. :) Also note: I've seen the rare earth magnets attached to a metal bar too and reading up on a couple sources for rare earth magnets (see K&J Magnetics), there are various configurations you can use to adjust the amount of force - i.e. one option is to just attach the magnet(s) to a metal bar instead of the wood, and the other to sandwich the magnet between 2 metal bars. Let me know how that works out. I'm building one now for my aluminum rollers with that method. BTW, you can pick up rare earth magnets at that same K&J for about $8 each.

+Don Dupuis Yup I was just reading through the comments to see if anyone picked up on that.

+Don Dupuis - No It' legit, it the aluminum only has to be electrically conductive. Circlar currents get set up in the aluminum that turn them into electro-magnets. Roland has it right. So does Nicholas Cristin, the aluminum would heat up.Part of the energy the cyclist puts in goes into generating heat.

Don Dupuis, they are aluminum rollers. Check them out at Nashbar.com. They are called "Nashbar Reduced Radius Rollers" Then read the description: CNC machined aluminum drums, 85mm in diameter, feature sealed cartridge bearings for quiet, smooth operation. You can read up on how it works here en.m.wikipedia.org/wiki/Eddy_current_brake. Or just try it for yourself.

I litterally laughed out loud. Stainless Steel isn't magnetic. Double wrong.

Not true. I built the same thing 2 years prior and I think Roland had a bit of a sneak peak at it. Copying is a great form of flattery! Mine is adjustable with a small lever on the bars. Check out "DIY Motion roller trainer with resistance" and then read how an eddy currents turns a non magnetic conductive material into a magnet if it is spinning! en.wikipedia.org/wiki/Eddy_current_brake Enjoy!