Hi, I'm new to cycling and I bought a 2011 specialized sirrus sport and all summer haven't left pavement once and realize now I likely won't be any time soon. So, I wanted to get a more narrow tire than the stock 700x32 but I can't seem to find any info on my rims via google. They're Alex AS-14 and I was reading sheldon brown's recommendations for tire size so need to find out my inner rim width. I was hoping someone might know how to get this info or have recommendations as to what size tire I can safely use? Thanks.

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Midway, he answers your question, you can place the screen icon midway to view.

Sounds like you could get away with a 700x28 tire for your bike!

You can measure the inner rim width yourself. What kind of riding is this bike for? Long, fast recreational; around-town; longish commutes?

Any reason why you want to go for a smaller tire width? I think the smallest you'd probably be able to fit on stock rims are 28s. 25s are pretty small and going to be a big jump for rims that should be holding 32s. Wider tires usually mean a more gentle ride and the sirrus sure is a sweet ride.

If you are willing to get new rims for smaller road tries, it really comes down to a question of how much you want to spend at that point.

Thanks for the info. I ride pretty much for fitness/recreation. So I'm more interested in speed than comfort I think. After posting here I was reading some more and was looking at the option of maybe just replacing my rims as well. Not sure if I want to go that far though.

There is no guarantee that you will go faster on 28's than on 32's; narrower, higher pressure is generally lighter but not necessarily lower rolling resistance.

speed comes from your legs!

I was also going to post this bit with my first post, but I didn't want to assume you were thinking/told that thinner tires means faster.

To be honest, just forget about that and do ride the sirrus. While it might be true that you can get 'faster' on thinner tires because of roll resistance or whatever, you said you are new to cycling so your legs need to really be built up to notice any significant difference. If you are riding on the stock all condition sports tires, that is the same brand of tires on the allez, with the exception of thinner width. They aren't bad tires and I am sure there are better ones but it comes down to money again. Personally I am a cheapo so I'd ride those stock tires down first, then switch to something else more road oriented.

You can get 700 X 28c tires on there ok. It will make a bit of difference when you are going up hills. If you keep your tires properly inflated they will be about the same on flat roads.

There are 'touring' flat resistant tires and there are lighter 'performance' tires that make another small improvement, but still not too much. Lighter rims would enable you to put on narrower tires still and possibly use lightweight racing tires. The performance difference would be a little more noticeable, but still not night and day.

Also, smaller tires have a smaller circumference you may have to use a bigger gear when you ride, or spin your legs faster. And lightweight tires generally have more flats.

Personally, I would ride what you have until they are down to the casing, then think about changing sizes when you need new tires anyway. IMHO, you won't gain much by going to a 28.