700x20 instead of 23?

Hi everybody,

I am about to purchase new tyres for my bike. I currently have 700x23 installed, do you think I should change to 700x20? What are the advanatges of each? I use my bike on medium-long rides about 3-4 a week, what do you suggest?

Also, my LBS offer Michelin and Continental tyres, is there a model in particular that I should aim to purchase? I was looking at the Michelin Pro Race tyres or the Continental Grand Prix supersonic, any comments on these?

Thanks!!

 

Hi,
if you ride 3-4 times a week....you should not change from 700*23. with this you get many advantages, such as
* better road grip on wet surface
* a lot more comfort than with 700*20, vety much if surface is not completey smooth
* easier to get them on and off if you puncture

I think you will gain nothing by changing too 700*20.
the tyres you mention are very good from my experience.

ovi

 

Stick with 23mm - sounds illogical but they actually have less rolling-resistance than a 20mm.

Personally, I can never tell the difference between tyre brands whilst riding. I've found the Grand Prix's wear quite quickly, while the Michelin's tend to get small splits in the rubber. At the moment I'm trying Vittoria Evo Cx's and they seem OK thus far.

 

Would not use 20's on everyday rides,just racing. 23's are the choice of most but a change to 25's are happing little by little.

 

GuyStevens: does the thing about rolling resistance apply even if you are really light? I can imagine a 240lb rider on 20mm tyres is going to be really squashing them and so the rolling resistance might be high, but what if you are a 120lb waif?

 

I don't recall it discussung anything about the riders weight, but they do cover the topic of rolling resistance for various tyres.

http://www.terrymorse.com/bike/imgs/rolres.gif

http://www.terrymorse.com/bike/imgs/rolres2.gif

 

Stick with the 23's over 20's unless you're racing to win or something. The 23's offer more comfort and fewer flats. The 20's offer less comfort and more flats. If you're not racing you should even consider 25's. Even more comfortable and less prone to flats. Michelin and Continental both make good tires. Take your pick.

 

I have had very good results with IRC, Avocet, and Continental tires.
20 width tires are lighter, but not necessarily faster, and certainly not more durable or comfortable.
Conti Supersonic tires have very low rolling resistance, but they expensive, wear out quickly and are not very puncture resistant.
Following is a quote from the Continental Bicycle Tire web site:
"My Grand Prix Supersonics lasted much less than the former Grand Prix 3000, is something wrong with the product?

Actually this product is intended for race application, for time trials, generally for people who care very much for weight and the lowest possible rolling resistance.

This should not be the preferred tire for training, for allround application, i.e. for the majority.

We try to tell customers with a tire comparison on the tire box. The Grand Prix Supersonic gets 5 out of 5 for rolling resistance and grip/handling, but only two out of five for mileage and puncture resistance . This very much agrees with your experience. So your remarks are totally right.


We know that quite a few customers bought the Grand Prix Supersonic and should have bought the Grand Prix 3000 or Grand Prix.

Did your dealer promote the Supersonic and did he tell you about the pros and cons of the Supersonic?

Did you pay attention to the tire comparison chart on the box? We are interested in your opinion on this matter because we hate to have people use our products against our recommendation.

People how know about the Supersonic's features do like this tire very much, because it is extremely fast. And they know that the price for ultra light weight must always be paid in terms of mileage and sometimes puncture resistance."
I suggest you visit Continental's site and download their bicycle tire application information from:
http://tinyurl.com/3fmxq
Information on Avocet tires for road:
http://www.avocet.com/tirepages/carbon12.html
If you buy the Conti Supersonics stop back and let us know what you think.

 

It would only be a real advantage in a time-trial and then the difference will be marginal and mostly aerodynamic , or so says the theory .

 

The rider weight is one of the foremost issues in determining tire width. A very lightweight rider doesn't deform the sidewall (the source of most of the rolling resistance) and tread as much in contouring the contact patch to the road. Therefore, different rolling resistance optimizations come in play with differing rider weights. A 100 lb rider probably ought be considering 20 mm very seriously, a 240 lb rider probably should not be looking at 23mm tires.

A rider with too thin a tire for his weight causes excessive deformations in the sidewall in forming the flat contact patch that bouys him up off the road. A rider with too wide a tire sees more deformation (and hence rolling resistance) at the tread than was necessary for his weight.

 

Dont think so.

 

Deformation is a problem if you don't inflate the tyre

Supersonics are very light an if you are seeking a faster ride and enjoy spending $$ on your passion then it sounds good.

23c remove some impact from the road and are said to have less rolling resistance than 20c on rough roads for that reason. 20c tend to be lighter and on a perfect surface and well inflated provide better cornering and rolling resistance.

It depends on your priorities for

Durability,
Comfort,
Speed,
Expense

Hope that helps

Brian

 

Agree with ya on the 25's but with some manufactures the sizing is nominal. I tried a Michelin Carbon (25mm) in the rear for training, and it was too wide. (Would rub the rear chain stays).

 

I haven't had any experience with the newer Continental tires but I definitely prefer the Michelin Pro-Race over the older Continental "Ultra" line. The Ultras tended to form flat spots in the center of the tires very quickly. The dual compound of the Michelin's seem to keep this to a minimum and don't seem to offer and drawbacks.

As far as the assertion that 23mm tires offer less rolling resistance than 20mm, I'd be cautious about accepting that. Of course the only way to know for sure is to retain all other tire characteristics across the two sizes and do your own testing.

I was forced into a situation of purchasing a Specialized tire that listed as a 23mm but was several millimeters narrower than the 23mm Continentals I'd been riding. I only had need to change the back tire and found that the speed gain was easily measurable. (Somewhere in the neighborhood of 1 - 2 minutes over 15 miles!) Obviously the two tires had numerous differences so the speed gain can't be considered conclusive. The narrow tire lasted less than 1,000 miles, largely due to the fact that it was rather old, and slightly dry at the time of purchase. Michelin has certainly made progress over the old "Axial Pro Light" tires in the area of cut-resistance. The Pro-Race seem quite cut-resistant.

 

Mine arent.2 flats in the first 500 miles. I perfer the conti 4-seasons,2000 miles and no flats and going strong.

 

23c can be fast if the vibration from 20c is large. I noticed the difference on my track bike.

Brian