700x28c to 700x23c

[dauphin]

Would there be any speed advantage to going from 700x28c to 700x23c on my Specialized Sirrus? My LBS owner says the rims can handle 25s or 23s.

 

[gclark8]

Yes very much so. But choose a good tyre, Conti GP4000 or Ultra Gator Skins. For flat bar bikes, run the front 10 psi below the rear, say 90/100.

 

[mikesbytes]

Its not just about size, the quality of the tyres and tubes is important. GClark8 has suggested some good tyres, others may add to that list of choices such as Mitcheln Pro Race 2. Different tyres suit different riders and it should be noted that wider tyres have lower rolling resistence where narrower tyres have better aerodynamics [assuming tyres of the same quality], so it does depend on the speed that the rider rides at. Air pressure is important, there is a correct value for each tyre dependent on the weight of the rider and bike.

Another consideration may be to go to 25mm once your existing 28mm have worn out and then go to 23mm after the 25mm have worn out. 25mm are fairly similar to 23mm in performance and you may find the step from 28 to 25 a little less radical as that of 28 to 23.

I should ask, are you using cleated shoes that have a stiff sole and do not slop around on your feet? A quality cleated shoe will provide a considerable improvement over flat pedals or toe clips.

 

[daveornee]

Would there be any speed advantage to going from 700x28c to 700x23c on my Specialized Sirrus? My LBS owner says the rims can handle 25s or 23s.

http://www.analyticcycling.com/ForcesSource_Page.html
is an equation where you enter the specifications and get the results.
Narrower tires weigh less and have less aerodynamic drag.
Usually they have higher rolling resistance and shorter tread life.
Narrower tires also have lower profile, so you will need to reset your computer to get accurate distance/speed readings. Narrower tires tend to protect the rims less and have harsher ride.
It depends and the riding surface(s) and your weight as to whether the change to skinnier tires is a move in the right direction.

 

[dauphin]

Its not just about size, the quality of the tyres and tubes is important. GClark8 has suggested some good tyres, others may add to that list of choices such as Mitcheln Pro Race 2. Different tyres suit different riders and it should be noted that wider tyres have lower rolling resistence where narrower tyres have better aerodynamics [assuming tyres of the same quality], so it does depend on the speed that the rider rides at. Air pressure is important, there is a correct value for each tyre dependent on the weight of the rider and bike.

Another consideration may be to go to 25mm once your existing 28mm have worn out and then go to 23mm after the 25mm have worn out. 25mm are fairly similar to 23mm in performance and you may find the step from 28 to 25 a little less radical as that of 28 to 23.

I should ask, are you using cleated shoes that have a stiff sole and do not slop around on your feet? A quality cleated shoe will provide a considerable improvement over flat pedals or toe clips.

I been doing a fair amount of riding on 23's on other bikes so I am familiar with the different feel of the skinnier tires. It had occurred to me to step down to 25s first and I may yet do that. I weigh about 82 kg (181 lbs) and I have been running the 28s at 100psi in the front and 115psi in the rear.