Tyres for Zipp 404? 23/25c?

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mimason
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by mimason

PLuKE wrote:Update:

I have fitted a 23c front and 25c rear, which are Michelin Pro Comp mounted on 2016 404's

They feel very supple and smooth, with lack of road buzz which is great, I ran them at 110psi front and 115psi rear with Vittoria latex tubes.

Thanks
Luke


115psi is a crap load of pressure for a 25 rear. I tested this morning on a fast ride and break away group going with more pressure 90f/100r and found the ride too rough and felt I was bouncing around when riding over 28mph race pace. I am going back to 85/95 for tomorrow's 85 miler.

You may want to dabble at 100 or less up front with the 23 as well as under 100 in the rear with the 25 and see what works best for you. enjoy the wheels.

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welchy
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by welchy

I'm running 25 Conti 4Ks on the Zipp 404s 2016s too, they measure around 26.5mm/27mm when mounted up to the rim.

I'm running them front and rear about 100psi, I may switch it to lower on front as well. Running the 25s up front as this is what I had available.. May try 23, but only after this wears as it's very comfy and rides super well.

PLuKE
Posts: 219
Joined: Sat Aug 16, 2014 5:26 pm
Location: Suffolk, UK

by PLuKE

mimason wrote:
PLuKE wrote:Update:

I have fitted a 23c front and 25c rear, which are Michelin Pro Comp mounted on 2016 404's

They feel very supple and smooth, with lack of road buzz which is great, I ran them at 110psi front and 115psi rear with Vittoria latex tubes.

Thanks
Luke


115psi is a crap load of pressure for a 25 rear. I tested this morning on a fast ride and break away group going with more pressure 90f/100r and found the ride too rough and felt I was bouncing around when riding over 28mph race pace. I am going back to 85/95 for tomorrow's 85 miler.

You may want to dabble at 100 or less up front with the 23 as well as under 100 in the rear with the 25 and see what works best for you. enjoy the wheels.


I am new with 25c tyres, as I am 11st/70kg I was under the impression that 110psi was fine on the rear, I found it felt great, no hooping or jarring etc.

I shall have to try, lowering the PSI wouldn't cause an increase in RR, same with a higher PSI?

Thanks
Luke

PLuKE
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Location: Suffolk, UK

by PLuKE

welchy wrote:I'm running 25 Conti 4Ks on the Zipp 404s 2016s too, they measure around 26.5mm/27mm when mounted up to the rim.

I'm running them front and rear about 100psi, I may switch it to lower on front as well. Running the 25s up front as this is what I had available.. May try 23, but only after this wears as it's very comfy and rides super well.


They seem to come up similar then to the Pro Comp's. The 23c runs flush with the brake track, and the 25c rear has a slight overhang, maybe 0.5-1mm seeing as the 404 is 26.5mm wide at the brake track.

Luke

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fa63
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Joined: Mon Feb 19, 2007 7:26 am
Location: Atlanta, GA, US

by fa63

PLuKE wrote:
mimason wrote:
PLuKE wrote:Update:

I have fitted a 23c front and 25c rear, which are Michelin Pro Comp mounted on 2016 404's

They feel very supple and smooth, with lack of road buzz which is great, I ran them at 110psi front and 115psi rear with Vittoria latex tubes.

Thanks
Luke


115psi is a crap load of pressure for a 25 rear. I tested this morning on a fast ride and break away group going with more pressure 90f/100r and found the ride too rough and felt I was bouncing around when riding over 28mph race pace. I am going back to 85/95 for tomorrow's 85 miler.

You may want to dabble at 100 or less up front with the 23 as well as under 100 in the rear with the 25 and see what works best for you. enjoy the wheels.


I am new with 25c tyres, as I am 11st/70kg I was under the impression that 110psi was fine on the rear, I found it felt great, no hooping or jarring etc.

I shall have to try, lowering the PSI wouldn't cause an increase in RR, same with a higher PSI?

Thanks
Luke

Technically speaking, higher pressures result in lower rolling resistance, though not by much. If you are comfortable at 115 psi, then keep it there and enjoy the couple extra watts. Otherwise, you will probably find that lower pressure will be even more comfortable.

Try it, it is free to experiment with air pressures :D

mimason
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by mimason

...and too much pressure results in the tire bouncing over the surface. I think 115 and 25s for most roads is way too high....especially in the wet.

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fa63
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Location: Atlanta, GA, US

by fa63

115 psi with 25 mm tires is high if you are on the skinny side. If you are 100 kg like me, then 115 might be about right :)

I run 100 psi on 28 mm tires in the back. My skinny riding buddy runs 75 psi in the same size.

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mpulsiv
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by mpulsiv

Grill wrote:
ChanheeLee wrote:I recommend 25c

According to several test, 25c Aero effects are more spectacular.


Let's see those tests... :roll:


Don't make your decision based on personal opinions of others riders with no data to back up the statements http://flocycling.blogspot.com/2016/04/ ... study.html



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mpulsiv
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by mpulsiv

mpulsiv wrote:
Grill wrote:
ChanheeLee wrote:I recommend 25c

According to several test, 25c Aero effects are more spectacular.


Let's see those tests... :roll:


@Grill
I posted this before. Did you click on the link below?
Don't make your decision based on personal opinions of others riders with no data to back up the statements http://flocycling.blogspot.com/2016/04/ ... study.html
Racing is a three-dimensional high-speed chess game, involving hundreds of pieces on the board.

:arrow: CBA = Chronic Bike Addiction
:arrow: OCD = Obsessive Cycling Disorder

mimason
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Location: Florida

by mimason

Fa63, i was riding with a local Shimano rep this morning that is your weight or heavier. Hes a big boy 6'3 and 225-230 running vit corsa g+ 25s at 105.... maybe give that a go.

Grill
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Joined: Mon Aug 20, 2012 12:12 pm
Location: Oop North

by Grill

mpulsiv wrote:
mpulsiv wrote:
Grill wrote:
ChanheeLee wrote:I recommend 25c

According to several test, 25c Aero effects are more spectacular.


Let's see those tests... :roll:


@Grill
I posted this before. Did you click on the link below?
Don't make your decision based on personal opinions of others riders with no data to back up the statements http://flocycling.blogspot.com/2016/04/ ... study.html


Yes, and it confirms that wide tyres kill CdA which is what I was saying. I have loads more data than that also confirms what I'm saying.

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mpulsiv
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by mpulsiv

"25mm tires kill CdA", if that's how you'd like to phrase it. To put this perspective, FLO 60 used in http://flocycling.blogspot.com/2016/04/ ... study.html are measured at 18mm inner, 24.4mm at brake track and 26.9mm at max width. Zipp 404 Firecrest http://zipp.com/wheels/404-firecrest---carbon-clincher are measured 16.25mm inner, 24.7mm at brake track and 26.5mm at max width.

Inner width is the pivot of how wide the tire will measure. When you mount 25mm tire on Zipp 404 Firecrest, it will measure narrower in contrast to FLO 60. In conclusion, 23mm tires could be 4-5 seconds faster in 40km when traveling 30mph speed when mounted on Zipp 404 Firecrest http://flocycling.blogspot.com/2012/11/ ... amics.html
Racing is a three-dimensional high-speed chess game, involving hundreds of pieces on the board.

:arrow: CBA = Chronic Bike Addiction
:arrow: OCD = Obsessive Cycling Disorder

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ProfessorChaos
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by ProfessorChaos

PLuKE wrote:Thanks guys.

I had a look on Zipp's website, and they state the fastest option on Firecrest/wide rims is 23c front and 25c rear, so thats what I have gone with.

Most 23c from what I have seen come in at 25c when mounted. The Zipp's I have are max width of 26.5.

So I went with a 23c front, as per Zipp, I have 23c Schwable One now and they sit flush, so hopefully the Michelin Power Comp do the same, and the 25c rear will help with RR as thats where most of the weight is carried, and less of an aero hit seeing as the air has been moved by the seat post first, and if a flat happened then it would have 2mm of extra rubber to maybe help the rim from getting mashed.

Thats my theory anyway, and Zipp seem to conclude?


Yes this is the best to run a wider tire in the back. 24mm/FR 26mm/RR Turbo Cottons are the best if you're going with clinchers or Turbo All Around 2 if Tubular.

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pdlpsher1
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by pdlpsher1

For those who run different size tires, do you find the front tire get too old since they never wear out? I could see that as a downside. Currently I do a tire rotation when the rear tires is almost worn out. Otherwise the front one will probably last two years before they are worn.

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mpulsiv
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by mpulsiv

pdlpsher1 wrote:For those who run different size tires, do you find the front tire get too old since they never wear out? I could see that as a downside. Currently I do a tire rotation when the rear tires is almost worn out. Otherwise the front one will probably last two years before they are worn.


Tire width doesn't play a role in wear but weight distribution does as much as 30/70. Rear will always wear out faster. Put bathroom scales under the wheels and have someone hold you while you sit on the bike.
Racing is a three-dimensional high-speed chess game, involving hundreds of pieces on the board.

:arrow: CBA = Chronic Bike Addiction
:arrow: OCD = Obsessive Cycling Disorder

by Weenie


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