I've been thinking of getting a trainer for some indoor workouts this winter. I guess the two technologies are magnetic and fluid. When I visited the LBS, the kid who waited on me sort of sneered at the magnetic model and said that I "had to have" a fluid trainer. Thing is, there is about a $100 difference to go to the fluid style; I can buy a new CycleOps Magneto for about $180, with the equivalent fluid model more like $280 (and the LBS was trying to steer me to the yet more expensive Kurt Kinetic).

So I thought I'd put this before the "voice of reason" that I usually find in this forum. Are there really any major disadvantages to going with a decent-quality mag trainer for someone our age who is looking to stay in shape and get a good workout, as opposed to being on a serious training schedule? I'd probably just ride for maybe an hour at a time, and just hard enough to work up a good, but not dripping, sweat (or so I say at this time).

Based on your reasoning for getting a trainer, the Mag would do nicely. If you want to compare the ride to outdoors then the fluid would be the way to go. If you are training to race, then the upper end fluids are the tool you need.

At the risk of sounding like a four-year-old, I hafta' ask: But why?

I assume there must be a difference between the drag vs. speed behavior of mag and fluid. what is it?

You can go on line to the Cycleops site and view a comparison of "power curve" of the different trainers they sell. The power curve of the fluid trainer will be a curve where the the effort is compounded by how fast the rider goes. The mag trainer has a straight line increase of force needed to go faster. In real life riding somewhere around 17-19 mph the wind force will compound the effort needed to ride faster and that is reflected in the fluid power curve.

https://www.cycleops.cz/files/trainers.pdf

Doug,

I don't have any experience with fluid trainers, but have used a magnetic one for several years. It will do what you want it to do. What you might look at is the noise factor. I used to use a wind trainer prior to the magnetic and the noise was deafening. I couldn't hear the radio or anything else for that matter. The magnetic does make some noise, but it is acceptable. I don't know if all magnetics are equal in the noise department, but it might be worth asking about.

Fluid trainers use oil to provide resistance. It has the same speed/force curve as air, so it provides the same resistance at the same wheelspeed as you would experience on the road. But not creating gale force winds, it's as quiet as magnetic.

Of the two mainly available fluid trainers, Cyclops and Kurt, the Kurt is quieter and smoother.