Road Cycling - Help An Idgit Figure Out His New Wheels

Hi there. I just got some 700 X 38c wheels for my bike! Unfortunately, the tires that came with them stink and I'd like to replace them immediately. I'm having difficulty finding the ones I want in this particular size. Then I realized I don't know what in the heck 700 X 38c means and furthermore, don't know what kind of tires would fit on them (I see a lot of 700X23 700X25 700X28). As I said, I'm an idgit. Won't you please help?
I asked a lady at a bike shop which tires would fit those wheels, but evidently she was surging with Valium, as she kept saying "well, you can get some big ones or some little ones or some medium ones...". I tried explaining myself more clearly but got the same response. I refused to buy any tires from her, realizing some people are even more of an idgit than myself. Can anyone offer any guidance on how to estimate which tires fit these sized wheels? Thanks.

700mm is the diameter of the wheel, the width of the tyre, would be 25mm, 28mm etc. Your bike might have an upper limit as to the width of tyre it can take, but either of these would probably be okay.

Richard

One more factor: The "C" is a designation for the width of the rim. Basically any tire designated 700 C should fit the rim, whether it is 700 C x 19 or 700 C x 38. 19's are very narrow and 38's are pretty wide. Oversimplifying things a little, narrower tires are built for speed and wider ones for comfort. I ride about a 38 on my touring bike, and a 22 on my racer. Just because a tire fits your rim, it doesn't mean that it will fit your frame. Brake clearance is a consideration.

In a nutshell, any of the tires you have in mind should work. Hope that helps.

Learn all about it here: http://www.sheldonbrown.com/tire_sizing.html

I'm curious: What is it that "stinks" about your tires? And why did your new wheels come with tires in the first place? Did you buy them used?

700x38c is a hybrid bike or touring bike size, usually. What kind of bike do you have?

RichC

Yep
700c is a French designation for a particular rim diameter size. It is used in most racing, touring and hybrid style bikes.
The x38 is roughly the inflated diameter of the tyre.
A rim can take a range of tyres , depending on the width of the rim.
Narrow racing rims : 19-25mm tyres
Light touring/race training rims: 25-35mm
Heavy touring/utility rims : 32-48mm

Note that although these numbers seem precise, one company's 28mm will be the same size as another companies 32mm.

Since your bike uses 38mm you should be able to fit a tyre slightly fatter or thinner. On some bikes the clearance for wider tyres is limited by the frame or brakes, but if your bike takes 38mm, this will not be a problem.

Narrower tyres can be inflated to higher pressure, so will be more efficient. Fatter ones will absorb rough tracks better.
For everyday cycling, there is little need to go wider than 32mm. In this size there are some standard well regarded touring tyres like Continental Top Touring, Panaracer Pasela, and some others as well, but they are only available from proper bike shops.

A good tyre will roll better , last longer and be more puncture resistant. It is the easiest and best value upgrade you can make.

Thanks everyone for taking the time to answer my questions. Since someone asked me some questions, I realized I didn't state my case correctly. I didn't just buy new wheels, I bought a bike with these wheels - that's why the tires were on them. It's a hybrid bike. My opinion of them 'stinking' is because they appear to be out of balance as there's a wobble to them (it's not the rim) and they've got a general purpose middle of the road tread on them and I really prefer 'slicks' for city riding (one of reasons getting myself a hybrid). Thanks again for the input, people!

The best thing to do is look up the rim manufacturer's website and try to find out what tire sizes are recommended for your rim. In practical terms a rim that's optimal for a 37 might take a 32 or even a 28, but the narrower the tire the more likely you'll have problems getting it on and off the rim, and that the tire won't have a deep enough cross section.

A tire that "wobbles" sounds like a tire that's not mounted correctly. Are you sure the wheel is laterally true, and perfectly round?

I assume this is a used bike. or you'd be working with the dealer to correct any problems. If you're new to this, it would not be a bad idea to go to a good local bike shop and have the wheels attended to anyway -- have them re-tensioned and trued, and look at tires while you're there. Messed-up wheels are not uncommon on used bikes, and they don't get better on their own.

You're right that tread patterns aren't necessary for road riding; what counts is how much rubber meets the road. All other things being equal, narrower, high-pressure tires with slick treads are likely to be the most efficient, assuming equivalent rubber compounds.

If your rims are OK with a 28 or a 32, the Continental TopTouring 2000 and the Specialized Nimbus EX are two tires I've had good luck with (eg., no flats, many miles) on commuting bikes.

Good luck, and have fun with your new bike!

RichC

When ever you do get tires, get tires threaded with kevlar, they last much longer.