In the grand scheme of things, I'd rather get teeth drilled and fillings inserted, than spend an hour on the trainer.
I'm a big lad even at my skinniest, and my sitbones aren't appreciably larger than most people's. In fact, on Specialized's Body Geometry seat measuring device - a pad of memory foam on a ruler, basically - my ass measures slightly on the narrow side of average, at least for sitbone width. But I'm putting 30% more weight, and throwing an equivalent amount of greater power, than the average roadie, all of this on a surface area that rivals Danilo DiLuca's.
Okay, fine, my surface area is nowhere near that small. But my narrow-ass sitbones are no bigger than, say, Maggie's, and I'm puttin' more weight per square inch on them than he is. So it hurts.
Yep, my ass takes a beating like it was being initiated into a street gang.
On the road, this isn't a problem. I have a nice FiZik Arione saddle, which is about as comfortable as a sofa. It is firm, but a little flexy; narrow, but comfortable. I can't explain why they work, but if you're in the 30% of the population for whom FiZik saddles work, you are in for a treat, they disappear underneath you.
Where was I? Oh yeah, on the road, you rock, hit bumps, stand here and there, and most of all the highly variable nature of your power (pushing hard, soft, middling, standing, coasting) means that your butt both moves around a lot and bears a variety of different loads in a bunch of positions that may look identical, but which vary enough to relieve the pressure.
On a trainer, you don't move around enough, the load is too constant, you rarely stand up, and you basically wear a couple dime sized holes in your ass. At least you do if you are me.
Boredom, severe overheating, boredom, and boredom aside, the aching ass problem is what kills trainer sessions for me. I can go about 10 minutes before my butt starts to hurt; by the 25 minute mark, I'm in hell with actual flames shooting out the legs of my shorts, at 35 minutes any nearby cats have been incinerated and my water bottles have steamed off, while by 50 minutes I'm looking at the clock every ten seconds to see if the clock has hit the 51 minute mark yet.
Since I sort of wrecked my early season by not hitting the trainer last winter when we got snowed in (some lung infection and travel issues notwithstanding) I vowed this year that it would not happen again. This means that I have to be ready to log serious trainer hours if necessary.
I realized I'd have to get rid of Old Blowtorch, aka my Performance fluid trainer, which was nice enough for an entry-level race warmup and short (one hour) rider, but which wasn't up to dealing with my issues.
So I decided to go with the Kurt Kinetic.
Kurt sells a bunch of trainers. The basic Kurt Kinetic is a fluid trainer with a several-pound flywheel on which your tire rests. It comes with an additional 6 pound flywheel, which gives added coast-down and gives the trainer a road-like feel. It isn't great, but the sensation of stomp stomp stomp stomp stomp for a pedaling cadence is definitely diminished. The next model in the line, the Kinetic Pro, comes with an additional 12 pound flywheel that bolts on to that six pounder very conveniently. This gives a *real* road feel. Seriously, once you get into a rhythm and keep your cadence steady, it will feel just like being on the road. It's uncanny.
Either of these basic trainer models can bolt on to Kurt's Rock & Roll base. This ingenious wide-footed base system permits up and down, and side-to-side motion as you pedal. At first it feels a little bit wobbly, especially on the very light 'spring' settings that I had dialed in. Once you get into a rhythm - noticing a theme here - it smooths out considerably and the wobble and bounce pretty much disappear.
They disappear, except for a delightful little bit of wobble and bounce that mimics road vibration and a natural, slight side-to-side rocking motion like you would have on a normal road ride.
The end result is pretty magnificent. I found that the sensation of sitting directly atop two upturned railroad spikes never occurred, and the ride was reasonably comfortable for the entire 2.5 hours I spent doing a zone 2 spin. Yes, I got a little bit itchy around the 90 minute mark, but that probably had as much to do with me wearing a pair of really crap shorts, as with the trainer itself.
Complaints? I still haven't figured out how to mimic climbing on the damn thing, but I have hopes; after all I only have 3 hours seat time on it. It's also a bit pricey, costing in the $400-$550 range, depending on whether you have friends in the industry or a good equipment deal through your bike club. But then most good bike stuff is too expensive if it isn't free, right? The other weird thing is that with the heavier flywheel attached, intervals are a bit tough. Sudden violent power pulses make the rear wheel slip, spitting rubber dust on the floor and failing to transfer power to the flywheels. (The problem more or less disappears with the lighter flywheel). With the Rock & Roll base - no relation to Michael Ball - it's probably not really race-portable. Sure, the legs come off real easy, but who wants to haul a 50 pound trainer rig across a wet field to the warmup area atop the runup at a cross race? Not I, I'll stick to my Schlockmeister 5000 Shitetrainer for that mission.
Good points? It's comfortable for the long haul. It's easy to envision doing long zone 2 rides on this when you're snowed in. It's definitely VO2 interval-capable; the only reason I noticed the wheel spin is that I actually tried a couple real sprints, something I'd never do on a Schlockmeister trainer. The base is enormous, giving it real stability; even though it feels wobbly at first you'd have to dork it up pretty badly to manage to tip this rig over. It's reasonably quiet - you can use this and keep the TV on "Cessna taking off in the distance" volume, rather than "B-52 hitting the water injection right in front of me" levels. And the final good point is that it has good road feel; the heavy flywheel gives it a natural feel, and does not encourage you to develop the trademark herky-jerky trainer pedal stroke.
The bottom line - pardon the expression - is that this is a trainer that even trainer-haters can embrace. It's comfortable enough to do your long base work on while watching Sportscenter (three times in a row) or to do heavy power intervals on. Couple it with a Powertap or SRM and you'll be in indoor, training data, why-ride-outside-I'm-only-here-for-the-dire-suffering heaven. Give it a shot if you're looking for a serious trainer upgrade, that will make your dire winter trainer sessions a lot less dire.
Don't buy it if: (1) your cycling is mainly recreational or commuting; (2) you have very limited space for working out; or (3) you seriously doubt your ability to stick to a hard, rigorous training regime with regular marathon (or short beatdown) trainer sessions.
Buy it if: (1) you need some way to wedge in very serious workouts of all sorts around your busy work and family schedule; (2) you are a serious cyclist (racer, rando rider) who *must* be in shape come spring, and your local weather frequently scrubs your training plans; (3) if you have the discipline to do heavy indoor training, which is still drudgery; (4) if regular trainers' goofy pedaling motion drives you nuts; (5) you have the cash on hand; and, most importantly, (6) if regular, non-flexing trainers simply give you a case of the ass, literally.