Road Cycling - Can I put a 700x28c or 25c on a Giant Cypress LX Rim?

I just bought a Giant Cypress LX for mainly road use (for fitness), but I wanted to make the bike a bit more efficient. My LBS says that I could put a 25c on the bike, so I opted for a 28c. The bike has a 32H rim and comes with 40c tires. I find it suprising that this rim could safely fit such a small tire when the standard tire is a 40c.

Is a 28c tire going to work well on that size rim?

Some damage to a disc in my lower back keep me off of a road bike currently. We will see what a year brings.

Thanks in advance.

28 mm will fit on a rim with a 17 mm inside rim-width which I'm assuming you have now. It's border-line though, but it's supposed to work. I wouldn't do it myself. I would not put 25 mm on anything wider than 15 mm inside width.

About three months ago I went from 38 mm tires & 17 mm rims to 25 mm tires and 15 mm rims. I saved something like four plus pounds in rotating mass. Did the same for the wife's bike. Made the bike sportier, faster and much more fun. Big improvement in handling/cornering.You won't reduce the weight and frontal area enough IMO to just change the tires.

If you do a google search you'll find about four places that sell Mavic Open Pro Rims on Ultegra hubs with Ultegra skewers for about $200.00 a set. Put some Continental Grand Prix 3000 tires (220 gm each in 25 mm) on them (about $100/pair) and you'll fly compared to what you have now.

The best deal (black rims and black spokes) was at Supergo when I did it. However, you have to order by phone from them. Their web site often indicates "in-stock" when they have none and they just pretend they never got the order. Happened to me three times.

Save the old stuff so if you sell your bike so you can transition the new wheels & tires to the new one. I'm in the process of doing just that for my new Ti Cyclecross frame set. The wheel/tire change made me realize that heavy bikes with wide tires are just not not all that much fun to ride.
----------------
When I wrote the above, I was thinking road bike. I didn't know you could get 25 mm tires in 26 inch. I thought yhey were only available for 700. I would think the rim-width limits would still apply.

Al

No problem. I've run road tires from 41 down to 23mm on the same wheels, and mountain tires from 1.25 to 2.3. Everything works.
FWIW, though, if you have a bad back and can't ride a road bike, aren't you working at cross purposes to put skinny road tires on the bike you CAN ride? If you're riding for fitness, there's no advantage to making the bike faster and easier to pedal--what matters is time and speed. Your heart doesn't know if you're going 21mph or only 16 with the same effort, and bigger tires are easier on you.

Thanks Al. I don't have the bike yet, they are getting it from another shop. They are also putting on a couple things like a cycling computer and tire/tubes. I don't actually know the rim width; I looked at Giant's website and found 32H.

Al, from your point of view what problems migh the 28c give me?

Thanks.

Velo Dog - Thanks for the info, I feel a bit better about fitting the 28c to that rim.


FWIW, though, if you have a bad back and can't ride a road bike, aren't you working at cross purposes to put skinny road tires on the bike you CAN ride? If you're riding for fitness, there's no advantage to making the bike faster and easier to pedal--what matters is time and speed. Your heart doesn't know if you're going 21mph or only 16 with the same effort, and bigger tires are easier on you.

I know what you are saying and I know in my mind this is the way I should look at it, but there is something that feels good about pedaling a more efficient bike (even if it is for fitness). I don't expect the bike to be too uncomfortable even though the tires won't give much, but the bike is probably more comfy than I need already with the front suspension and suspension seat post. My back likes the upright riding position more than anything. I guess it might be part "pride" in terms of my average speed, but again there is the cool feeling that every rotation of the crank gets more forward progress from the bike. Since I ride all pavement it just seems like I should optimize this part of the bike (cheap & easy gains) for my typical ride.

Thanks alot

Brownie

Anyone?