CerveloPro1

My kickr bike is a Cervelo R3 with a SL front fork. I swapped my Mavic Ksyrium Pro Carbon SL Clincher wheels on this weekend for an outdoor ride when I noticed that the front tire rubs the fork no matter what. It’s minimal but there and any debris picked up will surely make contact.

I run GP4000 25mm tires at roughly 95-105psi which I’ve heard are “taller” than avg.

My issue is Mavic states that you must use a 25/32 tube and you must run 25mm tires with these wheels.

Anyone have a recommendation for a lower profile 25mm?

Sy Reene

Per link below.. the Corsas measure at 24mm height on their test rim.
https://www.bicyclerollingresistance...orsa-graphene2

REDMASTA

gp5k

Mulberry20

The website BikeTire Rolling Resistance has tire reviews and tons of sizing data. You can compare multiple tires for a variety of metrics.

The Veloflex Corsa and Master are the lowest that I can see at 22 mm. They come carbon wheel compatible now. Those are wonderful tires and much more durable than they appear.

CerveloPro1

awesome information. Never been to that site before. Great! Thanks everyone!

Mulberry20

I haven’t been on the Veloflex in a few years but I am itching to grab a pair.

The family that owns Veloflex co-owned Vittoria at one time, when Vittoria actually made tires in Italy.

nomadmax 

I'd be happy if bicycle tire manufacturers put aspect ratios on tires. I get it that it changes with rim width but the trial and error method leaves a lot to be desired.

CerveloPro1

I need these pretty quick. Going to pull the trigger on some Veloflex Corsa SPS (carbon approved apparently) 25s on eBay. Hopefully they are the same dimensions as the one in the review from 2016. If it measures 22mm in height then ill
be good. I’ll advise how they work out.

Mulberry20

Grand Fondo did a review of the six best tires in its opinion and the Velos were the only ones that were true to size. World Class Cycles in Maine has them but the Masters are out of stock in 25, the tan wall is the only difference.

They are super supple like slippers for your bike, but they are fast too.

canklecat

Continental Ultra Sport II in 700x25 were barely larger than the 700x23. No problems clearing the frame and rear brake bridge on my '89 Ironman. Very under-regarded tires, especially for the low price. Not quite up to the ride of my 2015 or so Schwalbe One V-Guards, but not far from it either for a fraction of the price. And the cheap Contis are more puncture resistant and durable, while still being grippy on fast curves and moderately wet pavement.

But the Conti Grand Prix Classic (the handmade skinwalls) rubbed the rear brake bridge until I wore it down a bit on the indoor trainer and a few outdoor rides. It'll still scrape very slightly when I run through a puddle or wet dirt/gravel.

AnthonyG

There is no such thing as "low profile" bicycle tires. All bicycle tires are 100% profile meaning that they are as tall as they are wide. Low profile means that they are wider than they are tall but the only way you can make this happen is by having some stiffness in the construction that resists the force of the internal pressure to evenly expand the tire in all directions. Since bicycle tires are so light in construction there is nothing to resist even air pressure. Maybe a thick tread can change the profile slightly and as it wears it will wear the profile "flat" but this is minor and not a "feature" of high performance road tires.

Sy Reene

Maybe in some theoretical universe you'd be correct, or perhaps it's true for tubular tires. but in the real world where a tube/tire profile is not really round (eg diagram below), the inflated height of a tire is generally always less than its inflated width as measured from the rim's edge. Here's a list of a lot of tires, each link brings you to a review where both the measured width, as well as height are provided. Good luck finding very many where they're the same and the width isn't in fact measurably wider.
https://www.bicyclerollingresistance...&min=6&minpr=6

AnthonyG

The tires height is measured from the bead. Not from the bottom of the rim. If you complete the circle that the tire is forming then the circle will be closed pretty much at the bead.

CerveloPro1

Great information guys thanks again. I was lying in bed last night and wondered if a tube swap would make a difference. The wheels have a sticker that says “Use 25-32 Tube only”. If I used a latex 25/28 would that work at minimizing the contact?

I guess I’m just perplexed at to how to make the entire wheel fit since you must use a 25mm tire.

Waiting for the Velos to come in. May prime me some Corsa 2.0s just to try and see if those work as well.

Sy Reene

Maybe that's how you measure it, but it's pretty meaningless in reality.. and how do you get a caliper or ruler down where the bead is to take that measurement anyway?

biker128pedal

Conti 5000s in 23mm will measure about 27mm wide. Shorter and narrower than the 25mm.

oh. That’s on a 19.5mm inside width rim.

alcjphil

All that an inner tube does is to fill the interior volume of the tire. Once the tire has been fully inflated, it doesn't matter what is inside

AnthonyG

Any measurement involving wheels and tires are difficult to make. All official measurements of wheel rims are referring to the bead seat diameter (BSD) which is an internal measurement. It's not the bottom of the rim, its not the top of the rim, its in the middle. A 700c wheel rim has a BSD of 622mm. Good luck in trying to measure it.

Bicycle tires are 100% profile so a tire that measures 25mm wide is going to be 25mm higher than the bead + the thickness of the tread.

mikeread

What is the difference between buying a 25mm tyre that measures 23mm and buying a 23mm tyre that measures 23mm!

Surely the only difference is what is printed on the tyre wall. So couldn't you just look for 23mm tyres.

I would ask Mavic to explain the 25mm only instruction, doesnt make much sense to me.

Leisesturm

I agree and was reading patiently through earlier posts to say exactly this. Seriously, I would like a link to the information that we are being given by the o.p. I think something is being taken out of context or some other mis-communication.

canklecat

Try the Continental Ultra Sport II in 700x25 and Conti Grand Prix Classic (700x25 only) on the same rims. There are slight differences, enough that the USII will easily clear my Ironman while the GP Classic scraped the rear brake bridge until it wore down.

But the tread designs are different. The Ultra Sport II is a slick (with Conti's odd arrowhead pattern on the shoulders), while the GP Classic is a 1970s-'80s style tread with a slight raised center rib, and shallow sipes and chevron pattern on the shoulders. And the Ultra Sport II are mass produced (Indonesia, I think) while the GP Classic skinwalls are touted as handmade in Germany. I like both equally well but fitting the GP Classics can be tricky on old school bikes from an era when 700x20 were standard and 700x23 was a "fat" tire.

AnthonyG

Which is all fine. As I said in a follow up post, the height of the tire will be the width + the thickness of the tread.

The Ultra sport II is 100% profile. The GP classic with its thicker tread is OVER 100% profile.
It's standard profile vs HIGH profile.

Sy Reene

All I came up with was eg. link below, if you go to the "Intended Use" section within the top Specifications category

https://shop.mavic.com/en-us/ksyrium...html#1028=3283

shelbyfv

FWIW, my friend is unable to use 25s on his R3. You may find the same.

mikeread

Reading the Mavic info it recommends 25mm to 32mm tyres. I presume the wider internal rim width means that smaller tyres might not be ideal.

I would just find a tyre that fits and not worry too much about what is printed on its side.