kosmo886

Any thoughts on which of these would be faster? Essentially I’d love to go with the versatility of a 32mm, but don’t want to give up speed if there is much difference between this and the 28mm. What do you think?

Finally...how would these compare to the MAXXIS Velocita 40mm which is described as a high volume endurance slick.

This is going on a Giant Revolt Advanced 0.

Rides4Beer

Probably no noticeable difference in speed, lil more comfort and grip with the 32s tho. I'm running 32mm GP5K clinchers and they're great.

Dean V

You have a Giant Revolt and a Cannondale Topstone?

alcjphil

How bad or good are the roads where you live? Where do you live. Around Montreal where I live roads are frost heaved during the winter resulting in very rough pavement year round. Roads are cracked and broken and poorly repaired. There is a condition on some roads I call "faux pave" feels like cobblestones but doesn't look as attractive. On good roads 700 x 25 is fine, but 700 x 28 feels better. On bad roads a good lightweight tire like the 700 x 32 GP 5000 will glide over the broken pavement much better than a 700 x 28 which will have to be run at higher pressure. The worse your roads the faster a wider tire will be compared to a narrower tire

kosmo886

Just the Revolt. Had the Topstone ordered and when I went to pick it up I was able to do a side by side ride and the comparison wasn’t even close!

kosmo886

I am in MA...roads are crappy typically. I’ve been leaning toward the 32 for this reason as well. Just don’t want to give up much speed. Seems like I will have to replace the 40mm tires that are stock though. They are “slicks” but still gonna loose some speed there.

Iride01 

You keep track of your ride data don't you? Run one set for a full season of riding then run the other set for a full season. Compare rides on the same routes and let us know in two or three years.

WhyFi

You're probably not going to notice any meaningful difference between the two when it comes to ride time over a given course, but you may notice a difference in feel between the two depending upon your weight, roads, riding style, rims, etc. Second-hand experience probably isn't going to meaningfully convey the nuance between the two and, in the end, we're talking about consumables. Buy both, wear 'em out and form your own opinion.

Sy Reene

Put a 28 in the front and 32 in the rear; if the bike's wheelbase gets longer then the 32 is slowing you down. If the wheelbase shrinks then the 28 is slower.

PoorInRichfield

I have the GP 5000 TL in size 700x32c and setup tubeless on my bike and I love 'em. I was previously running 25c and 28c tires. With wide rims (mine are 25mm internal width) and lower tire pressure (~65psi), the 32's are the most comfortable road tire I've ever used. If they're slower than my other tires, I'd have no idea as I don't race (although I tried to ride fast.)

Roads I ride on often look like the following (of which this IS one of the roads I ride), which is why 32's have become my new best friend...

Dean V

How were they not even close?
Did the Topstone have the lefty fork on it?

HTupolev

If you have a reason to err wide, err wide. Even on a perfectly smooth and clean surface where there's no obvious benefit in 32mm over 28mm (except for maybe wear life), the performance penalties of a few millimeters of extra tire width are minimal. It's possible to distinguish the added aerodynamic drag by doing careful testing, and physics allows us to predict and model the kinematic effects of the added weight, but these aren't impacts that are casually noticeable on the bike or when just eyeballing average speed data on Strava.

Hard to say without testing. Some casing construction factors, such as protection layers for cuts and punctures, can have big effects on rolling resistance. When comparing two slicks, the performance differences from these factors can often play a significantly larger roll than more visible things like tire width. In extreme cases it can even be the other way around: even on a smooth road, a fast 40mm slick can sometimes be faster than a slow 28mm slick.

It's likely that the two GP5000 options perform much more similarly to one another than either does to the Velocita.

kosmo886

No lefty fork. Was the 105 Carbon vs. Revolt Advanced 2. both in the 2500-2800 range price wise. Very different ride.

kosmo886

Makes sense. I know none of this is an exact science. will be tough to compare side by side given the need to change the tires. That said, I think it's a safe assumption that the 32mm GP 5000 will be noticeably faster on the road than the 40mm Velocita. I've also read some interesting tests comparing the GP 5000 line and finding that width doesn't matter much between the few sizes depending on pressure and ride conditions, which in the real world are never all that smooth...hence the slightly larger may be just as fast and certainly a bit more comfy.

ups

No real difference in rolling resistance.
https://www.bicyclerollingresistance...endurance-test

Going from a 40 to a 32 is an easier transition than 40 to 28.

smashndash

I think the wide tire discussion is much simpler than most people make it out to be. Think about it like suspension on a mountain bike.

Regardless of whether you have a 23 or a 32, you can run a certain pressure to achieve the same amount of comfort over mild bumps. The difference is that, with big hits, you will crack your rims riding 23s but be fine with 32s. The only penalty to wider tires is aerodynamics (lol) and weight (lol again).

eduskator

Heeeeeeere we go again

Tacoenthusiast

If faster was the real driving factor shouldn't you be on a roadbike instead of a gravel bike?

Go with the bigger tires, it'll be more comfortable.

Wooderson

In the past year, I've ridden GP4K 700 x 25 which were 28mm wide, GP4K 700 x 28 which were 31mm wide. I'm currently riding 700 x 32 tubeless tires that actually measure 32mm, and while they're super plush, they just feel too wide to me. I notice the weight. I feel like the 'wider is always better' mantra is valid up to around 30mm, but beyond that, I do think the weight and aero become a factor. I know this is controversial, and I freely admit that it could be in my head. I don't care what internet rolling resistance studies say, I know how my bike feels on my routes with different tires.

Anyway, I'm mounting a new set of GP5K TL 700x28 this weekend. I think this will the optimal tire for my riding style. I'll probably run them at 65/60 psi (maybe lower, I will experiment), I'm pretty sure I'll get almost all the benefit of the 32mm tires I'm using now. I'll post back in a month or two with the results.

August West

I've ended up with 32mm as my go-to tires. But I ride on a bunch of god awful chip seal roads with plenty of cattle gates for extra fun. If I road on good roads I'd probably drop down to 28mm.

Sy Reene

Exactly.. give it a couple more years, and we'll more sensibly be riding stuff like this.

smashndash

We’re getting closer. 3T is launching a 29i/40e aero rim that’s optimized for 35mm tires. They believe that’s a fine size for regular road riding.




^this is with their old 25i/32e rims