titani

I am trying to make my caad8 smoother. Aluminum frame, carbon fork, 23mm tires. If I swith to 25mm tires, will I have a substantial improvement? I currently inflate to 95psi. Anything above 100psi makes the ride harsh on the cement trail I frequent. Thanks.

rpenmanparker 

Run your front lower than your rear because there is less weight on the front. What do you weigh?

BoSoxYacht

wider tires like 25 mm PRO4 Endurance will help some.

pinoy92231

I used to have 23s on my bike and now ride 25s. Same make and model tires. People say you can run lower pressures on a 25 than a 23 which I do. My bike feels substantially smoother with a little less pressure and with the wider tires.

TrojanHorse

A little lower pressure and yeah, it'll be a little bit smoother. Wider rims, wider tires both contribute.

hueyhoolihan

i've found that my 25mm clinchers run softer even at the same PSI as my 23mms. nice thing is that they can probably be run at a lower PSI too. only drawback is that they weigh a little bit more. most people don't seem to care about that though.

Ice41000

Smoother, yes. Much, no.

Decent carbon or titanium seatpost may help too.

Dan333SP

The brand of tire matters too. I went from crap stock Bontrager tires in 23 to GP4000 SII tires in 25 shortly after getting my bike, lowered the PSI to around 82/90 front/rear (I'm 175) and I could definitely notice a ride improvement with much less road buzz. There are probably other tires with an even smoother ride than the GP4s.

dvdslw

Aluminum frames are a bit more sensitive to small changes like tire size and inflation so you should notice a difference. For me on a Caad10, switching to tubeless made a huge difference in ride quality, something to consider if your wheels happen to be tubeless compatible?

Silvercivic27

23-25 = small differences, not big differences.

NYMXer

I recently switched my Cannondale Super6 Evo w/ Hi-Mod frame from 23's to 25's and am very pleased with the difference in the ride. Not only did the harsh ride go away, so did the twitchy handling.
I run them at 90 psi

Maelochs

I second the carbon seatpost idea, but only if you have a lot of seatpost showing--pretty sure two inches of CF is not a lot flexier than two inches of alloy.

I found an old NOS Bontrager on Ebay for $25 and I'd say (since it is all so subjective) that it really helps, and the cost was minimal--even if it had made no difference I could tell myself that I had saved 50-75 grams (worth 0.01 seconds if I ever climb Alpe d'Huez.)

titani

I am 190 lb.

titani

I guess I should check if the same rim accepts 25mm.

titani

Why do you think wider tires helped with twitchiness? My cadd8 is very twitchy, and I would like to solve that.

RR3

Bigger tires gives you more trail and a wider contact patch dampens any transient response.

Hypno Toad

My Felt Z85 is similar to your caad8, AL frame and CF fork. Funny story, I replaced my tires in June; 700 miles and 4 months later I realize that I'd gone from the factory original 25mm tires to 23mm with my new Vittoria Rubino tires. So, for me, there was no noticeable difference in comfort or performance switching from 25mm to 23mm tires.

For the record, I'm 165 lbs and I typically ride a 100psi on my road bikes.

NYMXer

I am guessing that a little wider footprint was just enough to cause that "skinny tire" balancing act to help ease that awful twitchy handling. I know there isn't a huge difference between 23's and 25's, but for my bike, there was a tremendous difference. Now, the handling is acceptable and the bike enjoyable to ride. I almost was going to sell it because I didn't care for the bumpy, harsh and twitchy ride. As a newbie to cycling, I didn't know what to do but I started a thread here, got some real good advice and made some adjustments. It was worth the effort

adrien

If you also go with an open tubular design (basically a tubular carcass designed for clincher wheels), you will also add to the smoothness. The supple cotton casing allows the tire to move more and allows for a lower pressure to be run. They are more expensive, and they wear faster. They are also sublime in terms of smooth feel, and the grip is extraordinary.

adrien

CAAD is a very aggressive bike, great for crit racing. It will feel "twitchy" to many, and is a reference for a quick-steering and feeling bike. The additional height of a bigger tire will effectively change the trail, which may have some perceivable impact on handling (because the geometry will be a few mm different). The bigger difference will come with more air in the tires, making the bike glide more over imperfections rather than bounce off them.

NYMXer

I agree adrien. My bike is the SuperSix Evo w the HiMod frame that I bought used for a great deal. After my first 30+ mile ride, I wasn't too sure about that "great deal" part. The biggest improvement was switching the tires, I like riding it now.

RR3

Going from 23mm to 25mm tires gives about 20% more air volume. Not much.

A bigger difference in comfort can be felt going to a supple tire from a stiff side walled tire.

Going from say Gatorskins to a Vittoria EVO CX Open Corsa would be an eye opener.

NYMXer

I went from 23 Schwalbe Lugano's to Michelin Dynamic Sport 25's. For me, I like the ride of the Michelin's and they are very affordable too with good thread life and flat resistant.

titani

Good Info. Thanks.

Dan333SP

If you left them at the same pressure after switching, that would explain why you didn't notice. The big ride quality difference from going 23 to 25 comes from being able to run them at lower PSI. For me, I've gone from running 100/110 f/r to around 80-85/90 f/r. Dropping 20 PSI in the rear tire definitely makes a difference, although I was running such high pressures with 23s not out of necessity but out of obliviousness.