tire sizes

backlippy said:

Hello,

I have an entry level Trek road bike 1.2. It came with size 700x25 tires on it. When I went online to buy new tires I see that the majority are size 700x23. I was wondering if I can buy these tires or if I would need to upgrade my wheels before the 700x23 tires would fit properly.

Any help would be awesome!

Brian

I am a relative rookie to road cycling. However, in my limited experience, you should be fine. I went from 700x32 cyclocross tires to 700x25 road tires without a problem. BTW, I am going down some more to 23's as well.

Brian

Going from 25 to 23 is no problem. Almost all bikes come with tires that are the middle size range that the rim will accept comfortably; thus you could go up to 28 or down to 23.

Switching from 700cx25 to 700cx23 is no problem at all. Assuming you had your 25mm tires inflated correctly, you'll have to increase the pressure in the 23mm tires by a bit......like 5psi....and you'll give up a bit of comfort.

You can't just arbitrarily make a comment about increasing psi by 5 without knowing more facts, perhaps the OP had the incorrect pressure in the 25's then what? that's right, incorrect psi for the 23's. So your assuming a lot by assuming he had his 25's correct.

So how much does the OP weigh? That's the big question about psi; and what does the max rated tire pressure on the sidewall of the 23 recommend? While that's not the right psi to use, but it does give us a starting point once we know his weight. Typically though you would have about 5psi less in the front then rear, if you, Alien creature, meant that then you would be right.

In 2009, the Trek 1.2 was spec'd with 700x25 tires, in 2010 with 700x23's.
Both have same "Bontrager Approved Alloy" rim. No issuer swapping tire sizes.

Tire pressure is a loaded topic. Here's what Michelin has to say:
The Correct Pressure

And here's a tire pressure calculator:
Bicycle tire pressure calculator

YMMV. ~OG

backlippy said:

Hello,

I have an entry level Trek road bike 1.2. It came with size 700x25 tires on it. When I went online to buy new tires I see that the majority are size 700x23. I was wondering if I can buy these tires or if I would need to upgrade my wheels before the 700x23 tires would fit properly.

Any help would be awesome!

Brian

700X23 will fit no problem. No upgrades required.😄