Norboo

I have a road bike (Trek 5200 carbon fiber frame) that has too aggressive geometry for this tired old body.
I recently bought a Trek D.S. 8.6 but seems pretty slow but comfortable.

What is a good comfortable bike to do a century on?

guidoStow

A big part of century comfort is a saddle you are comfortable on, a position that lets you ride efficiently without strain, gearing that will let you handle the terrain and clearance for large volume supple tires. There are material partisans who claim their choice of material is best, but if you get these four things solved there are a lot of choices that would work well.

Tailwinds!

mtn.cyclist

This is comfortable for me. I had a professional fit to set it up, which was life changing and I can't recommend it highly enough. Lots of comfort "features" built in like curved seat stays, titanium frame and saddle rails, carbon seat post with a little set back, carbon fork, 28mm tubeless tires. I added some headset spacers to raise my position a little and double wrapped the ergo shaped handle bars. That makes them a little softer and, more importantly for me, bigger diameter. You have to be somewhat prepared for a century length ride. I don't know your level but if you've never ridden more than an hour or something you're not going to be comfortable on a century ride. Be sure you have some saddle time in on similar terrain. Stay hydrated and take in enough calories on longer rides. Good luck, have fun!

bikemig 

I think a bike that you can use a 28 or even a 32c tire is going to be comfortable over long distances.

dim

I've owned several bikes over the past few months .... my most comfortable bike for longer rides is my Surly Long Haul Trucker .... it's not for fast riding/strava records though, but saying that, even with it's 26 inch wheels and wider tyres, it's not too slow

fit's me like a glove (that's the most important aspect together with a decent saddle) ....

mprelaw

If the frame fit sucks, tires won't make a difference.

Norboo

Fit was never an issue.

Norboo

Tried the 28's today for a short ride on my Duel sport hybrid, it's a rough ride but I will know more tomorrow after 25 mile test ride. You maybe right, 32's might work well but still would,like so other options to explore before deciding. Thank you

guidoStow

I use Compass 38's on my brevet bike. They are infinitely more comfortable than 28s. I weigh 195 and use 40psi front/50psi back. Comfortable and very fast...

tourisme

In my experience, "slow" and "comfortable" aren't usually compatible. One of the things that new riders struggle with when riding centuries, and longer distances, is just maintaining their posture and position on the bike, and the longer it takes, the more likely they are to get uncomfortable.

Whatever suits you, suits you, but personally I wouldn't recommend a hybrid as a century bike. Too upright a riding position means too much weight on the saddle instead of being spread between saddle, pedals and bars, flat bars offer too few hand positions and too much wind resistance in tough conditions, more weight than is necessary. Get a road bike that fits.

stevoo

Depends on the road conditions you plan to ride on. Just did the Tour of Unknown coast last weekend with a buddy. We each have new bikes this year. The roads were awful and really bumpy, pot holes, some gravel etc.
Each of our bikes rode way different.
One was pretty smooth, the other beat the living snot out of the rider. We had same tires and similiar tire pressures.
My suggestion is to rent your prospective bike and ride it on the roads you plan to use it on.
It sucked for him as his new bike rides so bad if the pavement has any bumps at all. Especially while decending a mtn at speed.
Marketing hype is just that. You need to test out your perspective bike and see if it does what you need.