See, for this fall-winter-early-spring, I’m considering putting my A bike on the trainer for the same reason. Not only can I spend time in the more aggressive racing position, but I like to use my B bike outside during the bad-weather months. Switching a bike from the muddy outdoors to a trainer in the living room is a pain.
I use my “A” bike, its the only bike I have, Scott Spark RC 900 WC. On the trainer for almost 2 years without issue. I’m not great about wiping sweat off my bike but I have a Lasko and 2 other fans on me, as well as a towel that I constantly wipe off with. I have yet to find a rusted anything.
I did that to a bike’s headset when I started riding the trainer a lot; I started using a folded full-size bath towel (fold it in quarters) over my bar/stem and have not had an issue since. Wash the towel with the bibs after the ride
I use my A bike and also my only bike for 2 years on Zwift and TR. 1st year I used a wheel on trainer and 2nd year Kickr Core. I have not noticed any damage or corrosion yet. If I get the opportunity to own 2 bikes I’ll definitely have one dedicated to the trainer for the convenience and less wear and tear on my outdoor bike. But for now I’m not concerned about it.
This. I changed my bar tape after 3 months of trainer use (with a sweat towel) and my handlebars were so corroded I had to swap them out. I had never seen anything like it, aluminum turned into white powder.
That might be the most common issue (or head sets), but the bars is a HUGE safety issue. I’ve seen them pics of them broken, which would be so bad inside, and potentially fatal outside.
Check your aluminum bars and keep 'em dry if at all possible.
One piece carbon bar/stem FTW!
Huh, another reason for me to look into carbon handlebars eh?
I could care less about breaking anything, but there is no way I can be arsed to do all the miniscule amount of work to take the bike on and off!
Old bike on the trainer all the way for me. It’s the same frame and set up identically so no way I’d bother with A bike.
Precisely.
I just use an old bike on the trainer, set up approximately like my main bike. As I’m in erg mode almost all the time I just stay in the same gear, so I can’t see the point of deploying my lovely Ultegra 2x11. The old bike on the trainer is not as effciient as my real bike so my effective FTP on the road is higher 
As far as I know Canyon still warns that using their bikes on a trainer voids their warranty — and they sell Wahoo trainers on their site and of course the pro teams sponsored by Canyon use trainers!
I had the paint start to bubble where the internal cable routing entered the frame.
I never cleaned my sweat off the bike though…
And ironically Canyon have a professional eCycling team, that use Canyon bikes on Wahoo trainers!!!
Yeah, I remembered hearing about it, but wasn’t sure anymore. Canon is really playing it ridiculous.
Was immediately thinking the same thing.
And if Alex isn’t snapping frames on his trainer, I’m pretty confident the average user is going to be just fine 
I have my oldest bike and groupset mounted on my trainer, doesn’t even have brakes anymore. I only take it off if I want to use the trainer to help me fit something on another bike before I take it outside.
Not at all concerned about hurting my other frames though it is nice not worrying about sweat corrosion etc since I’m using all old stuff that may never see the road again.
For me the primary advantage is that my road bike stays near the door ready to go ride outside and the trainer is just a matter of me hopping on when I need it. The less I have to do before any workout the better.
Cannot say that the crack occurred due to using on trainer but steel-frame seat tube developed a crack at the seat post slot that propagated around the tube and into the top tube. Manufacturer warranted the 15 year old frame & repaired it (replaced the 2 tubes & painted; cost of shipping 1-way only). The defect was found during a spring tuneup after riding on a trainer all winter. Pre-existed the trainer?.. dunno. Am gun-shy as i like the bike… need to get a trainer-only bike (& less hassle as noted above)