rangerov

The local LBS has a set of 700/20 tires I have been looking at. Will this change the feel of the ride? If so how much? I have always riden on 700/23. I did here that the 700/20 tend to flat less. I am not sure this is true. Thanks in adavance for your input.

sydney

There is no real point to 20s I pass even when they are cheap.

meme

A bit thinner tire requires you to pump the a bit higher pressure for the same amount of load. The ride is a bit stiffer; little bit less rotational inertia (barely noticeable). I haven't gotten to that point yet, but I've a feeling the 700x20 will wear a bit faster than the 700x23 or bigger tires.

ShinyBaldy

actually that's only in theory - someone on 20c may depress the tire because of their weight (how many PSI is a clincher wheel able to support?) resulting in more rolling resistance because the tire's contact patch deforms more than it would on 23c.

This is prob why most - if any use 20c clinchers, they're used on the non-drive wheel. Or if u are really lite...

chzman

I would at least try the 20s. What do you have to lose? a little cash?

From my experience, 20's will make the ride a little harsher. But I think the decreased width decreases resistance because of a smaller contact area. This should translate into more speed. Why would pros ride on 19s or smaller? Why do drag cars use those 4ft wide slicks with a low psi? For a larger contact surface to keep the tire from spinning.

I also think 20s are more prone to pinch flats, but not significantly more than 23s. Just ride on them and i think you'll like them.

sydney

that's just wrong... Everything else being equal,they will have the same contact patch.The 20s have to distort more to get it,therefore more rolling resistance. To get around that you have to increase pressure to get same contact patch....With pros, it's also about tubulars,higher pressure and smaller cross section and less wind resistance. ...BTW, are you a pro?

chzman

Nope, not a pro. Are you?

Sorry for the wrong info. But then why dont we use 25 or 27mm tires?

And when is everything else happen to be equal? Statistical theory? Different tires require different pressures. Please compare each tire at each optimal operating condition.

dwatson

I have 700x21 on my bike now, so I have the best of both worlds. I have riden the 20 and 23, you are not going to see a big difference between the two. My but tells me the 23 are a little more comfortable.

sydney

Everything else being equal,weight and air resistance.I have no issues with 25s. Some woud say that using anything less than 28s is playing racer wannabee.And so the world turns.....I've been known to play a pro on the internet.

Retro Grouch 

How much air pressure do you use? If you are using 700 x 23c tires now at, say 120psi or more you might as well go for them because you are using tire pressures now that are adequate to keep the 20's from pinch flatting.

At equal air pressures the 20,s will have slightly greater rolling resistance and slightly lower air resistance. Unless you are using some kind of laboratory grade instrumentation you'll never notice either. I wouldn't bet either way on that fewer flats story but I'll bet saying that helps them to sell tires.

rangerov

Thanks for the info I think I will pass on the 20's.