Order of easy upgrades that get a smoother ride?
 

I have an aluminum 2017 Tiagra Domane with the rear ISO speed coupling and a carbon fork, running 28c Conti 5000 tires. It's a fine ride, though I'd like to make things a bit smoother for some rough pavement patches in my ride. I only ride this bike on the road, so we're not talking gravel-level comfort.

Wondering about ease and cost of upgrades that could help:

1. Seat post - current seat post is round aluminum. Would an upgrade to CF help a lot? Clearly this is the easiest one :)
2. Handlebars - like the seat post, the handlebars are alloy. Would an upgrade to CF help a lot? This would be a bit harder, but I don't mind a project and I've not worked on bikes much before, so this could be fun. This is a non-integrated handlebar with mechanical shifting and rim brakes, so might be the easiest handlebar change? And what about the stem? That's alloy too. Any reason to go CF on the stem?
3. Tires - I changed out from the stock 32c Hard Case lite tires to 28c Conti 5000 on the suggestion of my LBS. I gained a +1MPH average, which was greater and the handling improved, too! But, this didn't help the ride. What if I went with a good 28 tubeless? Rims are TLR. Or should I just go back to 32, but a better 32 than the OEM? But with an internal width of 17, I wonder that 32 would impact the current handling.
4. Wheels - running the OEM Bontrager wheels (622-17), which are alloy and weigh about 1690g. Would CF wheels help a lot here? I'm a little hesitant to invest in CF wheels for this rim brake bike, though. So unless I would get amazing gains here, I am wondering if I can avoid this and just do the top 3?

Choice #3. Had you chosen your Conti 5000 tires in 700 x 32 you would have seen the same improvement in handling and a more supple ride than with your OEM tires. Also, check your tire pressure. If your are running the max pressure your tire is designed for, depending on your weight, you may be overinflated

Fatter tires allow lower pressure (squisyness).'
Gloves can counteract "road buzz" if that's a problem.
CF must have gotten extremely inexpensive for the negligible gains of the parts you list.
Why didn't you mention a CF fork, which could actually make some sense.

OP's bike already has a carbon fork

Thanks. I will optimize the pressure. TBH, I got a new pump with a more accurate pressure gauge (my old one was off by a LOT) so I have to relearn where I want them to be.

What are your thoughts on a seat stem - worth a move to CF? Same on the handlebars?

I have always ridden with gloves, but it's not the constant buzz that's causing issues. It's an area of "new pavement" a nearby town put down. It's like chipped rocks stuck in glue. I think it's called "chip seal" from what I just looked up, and is described as "An inexpensive alternative to asphalt concrete overlay, this treatment starts by having liquid asphalt sprayed onto pavement. Then, a thin layer of aggregate chips is placed on the asphalt, and a new surface is rolled so the two parts combine. Ultimately, a chip seal treatment can extend the pavement’s life for years."

It impacts ride comfort and even steering to a small degree.

There is a huge cycling population in this area, but when I called the town about it they said "don't worry - it will smooth out in a few seasons."

Tires are number one for pretty much any change you want to make to the performance of your bike. Install the widest tires that will fit in your frame and fork then experiment with lower pressures.

Next would be a suspension seatpost - I believe the 'parallelogram' style is more effective than telescopic ones.

Just curious, what tire pressure have you been using and how much do you weigh? My example: I have 700 x 28 tires on one of my bikes, I inflate them to about 75 psi and I weigh about 155 pounds

If the rims are TLR then just run 32mm tubeless tires. Tubeless tires are slightly smoother than tubed tires of the same width.
Carbon seatpost and handlebars do help a little bit, but not nearly as much as wider tubeless tires.

tires and pressure are the best value for the buck IMHO (and a good fit and gel Gloves)

I would go back to 32 mm, high end tires and light tubes

I like cont's 5000 and liked the ride on the 28mm (I am used to a firm ride)

suggestions for you
conti 5000 in 32

vittoria corsa control in 30

rene herse stampede pass (32) expensive but every one who has tried seems to love them https://www.renehersecycles.com/shop...stampede-pass/

A really easy one - thicker or padded or gel handlebar tape. Also - learning to "ride easy" on the rough stuff. More muscle on the downstroke to slightly lift your butt. Easy but secure grip on the bars, bent elbows, forearms acting as shock absorbers. I raced a steep criterium bike BITD on 21c? tires and 110 psi. Sometimes the pavement ended. (We were always told in advance but none of us changed anything.) I found I could do this "float" on the bike and all that banging didn't throw me off, hurt or even matter.

The "ultimate" solution (but that takes you back to square one) - big expensive tubular tires on matching tubular wheels with shallow, very forgiving rims and light butted spokes. "Square one" - this is a whole new (130 year old) game. Nothing about those tires, rims, repair, mounting, road side repairs ... is the same or compatible to anything you've ever used or done. But, the top of the line tubular tires have been called "magic carpets" for a long time. The best clinchers only come close.

I'm not recommending tubulars. They require total commitment. I rode and raced them in the '70s before there were competition grade clinchers (like everybody else). Loved them. Switched for good (so I thought) when I married as being wedded to both a wife and tubulars at the same time, well I think there are laws against that. Marriage fell apart. A few years later I rolled a clincher off the rim on a blow-out and crashed hard. After a decade of wondering "what if" on every should-be-fun descent, I went back for peace of mind. And got reminded, - yes! the magic carpets!

Look at my first paragraph seriously. (My concession to age is I now wrap my handlebars with two layers of tape. In a few years I may be doing innertube wraps and my favorite tape over that.) Being able to "ride light" is a tool you will never regret having. Yes, it is more tiring. (But when racing, it always moved me up the peloton a bunch of places so it was worth the effort; never mind that the ride felt better and safer.) You can read and dream about tubulars. But don't rush into them. I don't want you (or your significant other) cursing me.

Edit: 2nd the Vittoria high end tires. Every Corsa Open Pave, G+ and G2.0 I've ridden have been sweet rides. I've now ridden a couple of their tires in both clincher and tubular. Tubular wins and you need to go 2mm or more larger with clincher for the same cushioning but the quality and super materials are the same. I've got the 30 mm squirtdad talks about in tubular and haven't tried them simply because 28 is plenty.

I find the conti tires to have a terrible ride.

If you want a smoother or less buzzy ride then I'd suggest something from Rene Herse tire line, or the Specialized Turbo cotton, at 70-80 psi

then, yes, bar tape, gel gloves and all the other stuff.

But the tires are probably the biggest single thing

/markp

Tires: you might try the 32mm version of the GP5K, run it tubeless or with lighter tubes.
Handlebars: you might try a carbon bar with some nice cushy bar tape.

Your wheels are fine. And the isospeed seat mast topper - I doubt you'll notice a difference between alloy or carbon there.

Before changing anything, do as mentioned already and lower your tire pressure. Hard to say how low for sure as were missing some info such as your weight but when I want a cushy ride I keep lowering the pressure until it seems like the potholes/bumps etc. may cause a pinch flat. This will take a little trial and error. I use the 25mm 5000's and myself and bike weigh about 230lbs total ready to ride. I can go down to 80psi on the crap roads here without too much worry of pinch flats and your wider tires would allow even less pressure all other things being equal.

That would be a good reason.

If you’re trying to soften discreet bumps, both stems and seat posts are available with suspension. For instance, https://redshiftsports.com/pages/road. But chipseal falls into the category I would call buzz, which can really be tiring. Larger supple tires help as has been suggested. I’ve been happy with Schwalbe Aerothan tubes which slightly improve ride through both suppleness and allowing lower pressure. CF handlebars can help reduce buzz vibration by dampening the ringing due to resonances in the frame tubes.

Thanks all. These posts were really helpful.

This seat post:
https://na.tranzx.com/products/antis...uspension-post

I use it on two bikes. Works great, cheap too.

Upgrade:Tires. Handlebar tape.

The seatpost, handlebar, wheel changes will be very subtle, slight improvements.
I've never tried a suspension seatpost, they probably help. But aren't they more for soaking up big bumps than for rough road buzz? I don't know.

I don't think that regular road bike carbon seatposts have enough effect to be detected in a double blind test with the post covered up so it couldn't be identified. And aluminum handlebars are reliable and affordable. Carbon wheels? expensive. Are even the aero benefits of carbon wheels worth it? and carbon wheels aren't great with rim brakes.

Tires and inflation are by far the biggest change.

Drops
I like riding in the drops on very rough roads. Spreading the jarring load across my palms helps a lot. I have the bike fitted so that drops are comfortable, unlike many riders I know. I have the bars set a bit higher than they do, so I can ride either hoods or drops effectively.

Large tires
I had some 38mm Compass tires on my adventure bike (until one developed a bulge after normal riding.) 38 psi front, 44 psi rear. It was very helpful the day we hit fresh chip-seal, with large gravel chunks on the tar base.

I notice that my Ti adventure bike is "quieter" than my carbon road bike, which is "noisy" on rough roads. I think it's more of a perception of smoothness, the carbon bike absorbs road buzz quite well.

Now I have GP5000 in 28mm. I'd try 32mm if it would fit in my road bike, but that's a bit too tight. I don't like gaps between the tire and frame/fork that are less than about 4mm.

Tire pressure calculators!
These give similar answers and I really like the ride at their recommended pressures:
Sram tire pressure calculator
Silca tire pressure calculator. Very detailed. They recommended a few psi higher on very smooth roads, a few psi lower on rough roads.

At 165 lbs and approx 20 lbs of bike+accessories: 28mm road tires: around 70 psi front, 72 rear. I have been running 68-70 front and 78-80 rear. reducing the rear pressure to 72 was good.

^^^This. Bontrager Hardcase tires are pretty harsh. Choose any high end tire in a 700 x 32 and lower your pressure.

Anything else you do will be hardly noticeable except thicker handlebar tape.

While they may have been shock absorbing at one time, I sincerely doubt any modern carbon bar or (especially) seat post ride any different than alloy. Light is stiff, stiff is strong.

Always wider tires always! Good wide soft supple tires will improve the ride quality of pretty much any bike. Carbon Fiber stuff is not really going to give you enough benefit to make it worth the money but tires most assuredly. Most of my bikes are pretty near maxed out on tire size (without causing issues) and I wouldn't go back to skinnier tires.

If you want more comfort than that: https://cirruscycles.com/products/ki...nsion-seatpost. They make a crabon version of it I am currently running two on different bikes and they are fantastic and will remove all the road chatter quite nicely and it is tuneable for your weight or riding preference.

OP's bike has an Isospeed decoupler, so all the seatpost-based suggestions are not feasible.

There is definitely consensus that tires are the best (only?) change worth pursuing.

Handlebar tape or under-tape cushion would make a difference as well, but it would also change the grip. I went from standard tape to thicker tape and it made my bars feel really thick. It's soft and cushy and grippy but I can't get over how fat they make my bars. YMMV.

My two smoothest bikes have carbon drop bars. Is it due to the bars or due to something else on the bike? Hard to say, but at this point I'd prefer regular tape over carbon bars than cushy tape over alloy bars.

The only problem I have with a suspension seatpost like this is that your saddle height effectively changes with every flex.

Tires! I'm a big fan of the Soma Supple Vitesse EX, and they're currently on sale too:

https://www.somafabshop.com/shop/som...attr=3482,4273