Readers submit stuff to us all the time which we love and encourage, however Bike Hacks had never been contacted regarding a "guest author" type of post. I am no expert in bike trainers, I would rather go ride my bike in sub-zero temps than drip sweat and go no where inside, so when we were contacted by someone with expertise in the area it was a no brainer for a post to add value to overall knowledge base of Bike Hacks.
Ron Fritzke is the one who contacted us and he put together the following article for the site. If you have experience/opinions/advice regarding trainers feel free to comment. All text and pictures are credited to Ron.
How Do Bike Trainers Work?
I'm a new reader to BikeHacks, and I'm duly impressed with the hacking abilities exposed on the site. When Matt agreed to accept a post from me, the 'hack' angle had to be nailed down. No sense posting a boring article like the ones lulling the rest of the internet public into a semi-cognitive stupor. After all, that's what my website's for.
I write a cycling-gear review site and my latest passion's been indoor bike trainer reviews. Matt pointed out that even a commercial bike trainer's essentially a way to hack the weather. And that's true, but there had to be more of a BikeHacks angle to it...
So here goes with my explanation of the three types of bike trainers...with a challenge to Bike Hackers everywhere to insult the sensibilities of cyclists on store-made trainers, especially those who show up to spin classes. It's time to transform junkyard scrap into hacker versions of Kurt Kinetic trainers. There are basically three types of indoor bike trainers in the world. Each provides resistance to the rider in unique ways with various strengths and pitfalls associated with each style.
Wind Trainers Are The Simplest To Hack
If the hacker's looking for simplicity, this would be the type to check out. This most basic of designs isn't much more than a spinning impeller (or for the brave hacker, a propeller) going through the air. There isn't too much that can go wrong with this design, besides severing ears and fingers...or maybe dislodging knick-knacks from the fireplace mantle if the design is too aggressive.
I'm sure you've been exposed to human-powered everglade style boats using airplane propellers and pedals (who hasn't?), so creating a land-locked version of the such a beast shouldn't be too complicated. Wind trainers are the noisiest trainers, with some apartment dwellers finding them horrendous in the 'meet your friendly neighbors' department.
Additionally, intense cyclists will likely find these trainers to be lacking in the resistance department. While a casual rider on a steady state ride may get enough of a workout from a wind trainer, someone looking for an intense workout may do well to look toward a fluid trainer. Then again, if the propeller's big enough...
Fluid Trainers: Intense And Leaky
Fluid trainers provide resistance just like wind trainers do, except under water...sort of. They actually spin an impeller through a thick fluid such as silicone. This is the class of bike trainer that can handle the efforts that even the stoutest of riders can dish out. The harder the cyclist pedals, the more the trainer resists. And I don't mean linearly, either.
Looking at a speed vs resistance graph, you'd see that a fluid trainer provides an intimidating resistance slope that gets steeper and steeper until it almost approaches vertical. These trainers are optimal for riders who'll be doing periodic high-intensity workouts. Fluid trainers are also the type of trainer that have been notorious for leaking all of that precious silicone fluid onto the floor.
So before the Bike Hacker gets too smug about merely spinning an impeller through maple syrup, be aware that keeping the fluid in the chamber's been an ongoing problem that's eluded everyone except those who've manufactured the Kurt Kinetic Road Machine. It seems all of the spinning of the shaft through the o-rings, coupled with the heat generated by a vigorous workout have been too much for first generation fluid trainers.
When the Kurt Kinetic company came out with the predecessor to the Kurt Kinetic Road Machine, they nipped the leakage problem in the bud with a new proprietary design. Instead of having a shaft penetrate into the silicone filled chamber, they sealed off the chamber and coupled the impeller in the chamber to the outer flywheel with the use of magnets. Both the impeller and the flywheel have six strong magnets in them, and when they're put close to each other (on separate sides of the seal) they form a nearly unbreakable magnetic bond. Presto, no need to violate the seal of the fluid filled chamber.
Their design is protected by a patent, so it left CycleOps and the other fluid trainer manufacturers scrambling. I'm not sure what they did in response, but I do know that the number of leakage complaints on all fluid trainers, including the CycleOps Fluid 2 bike trainer have dwindled. I suppose higher quality parts (including o-rings and shafts) translated into more reliability.
Magnetic Trainers Suffer From Middle Child Syndrome
Wedged between wind and fluid trainers are the Mag trainers. Unlike the Kurt Kinetic Road Machine which uses magnets to form a magnetic coupling, mag trainers use magnets to create resistance by repelling one another. By placing magnets in a configuration that exploits the magnets ability to repel each other, Mag trainers create a workload for the cyclist.
In the past, these trainers with all of their moving parts, were famous for starting to rattle and bang. Before long, parts were working loose and smacking into each other. But the bike trainer world has become far too competitive these days for junky products to have survived in the current market, so today's Mag trainers are pretty reliable. But don't despair, there's oodles of room in the Back Hacks world for Mag trainer clunkers and clangers. So put on your thinking-caps and break out the welders.
Innovation's Not Limited To BackHacks.com
Speaking of innovative uses for magnets...during the height of the Nikken healing magnets craze, a patient arrived in my office with a magnet from the base of a CB antenna strapped to his lower back. Seems he'd rather get the healing energy from Trucker Ted's throw-away antenna than spend hundreds of dollars for an undersized splinter of high-tech Japanese magnetic marvel. Go figure...but it sounds kinda hacker-like to me.
If he could read, I'd turn him on to BikeHacks.com.
About the author: Ron Fritzke is a cycling product reviewer with a passion for ‘all things cycling’. A former 2:17 marathoner, he now directs his competitive efforts toward racing his bike…and looking for good cycling products.

Cool. I've been wanting to know more about bike trainers. I've been more of a ride around in the cold and snow type but there are times when that is unappealing.
What about bike rollers?
Posted by: Jody Benedict | 02/09/2011 at 06:04 PM
Jody,
Thanks for reading the article on trainers.
I'm not sure which questions you have about rollers, but I wrote a page on them a while back. It discusses the benefits and pitfalls of the various features. Here's the page... http://cycling-review.com/accessories/buy-discount-bike-rollers/
Posted by: Ron | 02/09/2011 at 08:21 PM