Bicycle Mechanics - Quick Tire Question (I Hope)....

Hey all...

Very quick question, I hope, from a guy who, in the past few months, has gone completely cycle-phsycho in love with riding, fixing, restoring, bikes....

I very recently picked up a beautifully kept 1989 Nishiki Sport 12 speed. I got her all tuned up, cleaned up, tweaked up, and just about ready to take on some long rides & commutes, except one thing, the tires. They are pretty old and crapped out.

Right now, they have 27 x 1 1/4 inch wheels and tires, the front semi-slick, the back your basic Bell cheapies. On my main bike, I've become VERY accustomed to my 700 x 23 and would like to take the Nishiki to a skinnier tire on it's current stock wheels.

I'd like to go to 27 x 1 1/8th faster/semi-slick tire but because I can't find any at the 1,000 LBS's, before I go and do the online thing, get them, see they don't fit, cuss and swear at the cycle gods, then deal with online returns, I thought I'd ask you brilliant fellow cycling freaks. I've searched various threads, sheldon brown, etc, but the info just seems all over place and is starting to get a little gobbly-gooky...

So, will they fit?

Or are they too narrow and these wheels are destined to hold 27 x 1 1/4 tires?

Thanks so much for your help!

Edit --- Oh, here's an updated photo of my 19 year old baby:

http://img300.imageshack.us/img300/9261/dsc0003nishiki800nj8.jpg

Probably they'll work. It depends on the inside width of the rims. I think that Sheldon Brown has a chart on his website that has the answer that you need.

Thanks! Yeah, I've gone through his site, and have read that page a number of times. I guess I'll take the tires off tonight and start measuring. It's amazing how messy the tire sizing has been over the years. You'd think something as simple as circles would be pretty straight forward.

Thanks! Yeah, I've gone through his site, and have read that page a number of times. I guess I'll take the tires off tonight and start measuring. It's amazing how messy the tire sizing has been over the years. You'd think something as simple as circles would be pretty straight forward.

What can I say?

A bike is a pretty simple machine but every single part on it, if you dig into it, gets more involved. The basic concept is simple, the execution isn't.

The quicker somebody gives you a pat answer, the less likely it is that they understand what they are talking about. If your rims are too wide for your tires, you'll get frequent pinch flats.

good point..... Just was hoping this was one of those simple "hey noob, of course they do/don't fit!" kinda questions. I'll do some measuring tonight. I put these guys in my cart at nashbar:

http://www.nashbar.com/profile.cfm?sku=12750

Then make the call tonight.

Just find it funny/ironic that, as a guy with a chemistry degree, who studied physical chemistry, engineering calculus, etc, etc, for years, can get baffled by something as seemingly simple as a tire size on a 20 year old bike!

lol.

Oh well. Thanks for the advise grouch.

Remember that you're only allowed to take pictures of your bike in front of a white garage door...

Remember that you're only allowed to take pictures of your bike in front of a white garage door...
Sum ppl are in love with bricks. :)

OP, so u already knew the answer, but are lazy to take off the tire to measure? Did u think we have remote tri-corders or sumthing?

No... this weekend, I did everything but take the tires off and measure. She's running great now. I just figured I'd buy 1 1/4ths....

But at work today, the thought of going to 1 1/8th was nagging me. And so I read back up on it again, and just figured I tossed the question out to you guys (who are much more knowledgable than me) here to see if anyone had the quick "yay" or "nay".

It's cool, I'll pull it off and go through the motions.

Thanks anyway!

And yeah, the multi-colored bricks.... has a kinda urban-camouflage effect, eh?

Just find it funny/ironic that, as a guy with a chemistry degree, who studied physical chemistry, engineering calculus, etc, etc, for years, can get baffled by something as seemingly simple as a tire size on a 20 year old bike!.

Why do you find that ironic?

The older that I get and the more that I learn, the more I realize how much I don't know. Even worse, the body of knowledge for stuff that I think I have a pretty good handle on is changing at a faster rate than I can keep up. If you thought your chemistry degree should have somehow infused you with knowledge of bike tire sizes, you probably wouldn't be a very good chemist either because you would have stopped trying to learn.

I'd have no qualms about swapping to a 1-1/8" tire.
You would be going from-
630-32
to
630-28
(MM)

Yes, they will fit. Trouble is not too many of those 1 1/8s available.

I've gone down to 27x1" on rims that originally had 27x1-1/4" tyres. These where single-section Araya rims of some sort. Worked perfectly fine and I eventually rebuilt the front-wheel to 18-spoke radial for fun. That lasted for about 1-year and about 7000 miles until I plowed into the back of a parked car.

thanks all..... after a bit of measuring, and double checking, and re-checking this thread, I went ahead and ordered the 1 1/8ths from nashbar...

On a fun note, put on my Xero Lite 700/23 wheels and a 6 speed freewheel I had, really cool. Liked the look, rode pretty smooth (needed more tuning). When I get the new tires, not sure where I'll put the 27s, either on the Nishiki or on the World Tourist Single Speed... Probably do some test rides and make the call... Until then, the Nishiki is back in the basement, waiting for her tires.

Anywhos... thanks again all.

And the irony, my dear grouch, comes from the intense mathematics, the constants, and the exactness from my studies back in the day. Pretty straight forward stuff, of course with new discoveries come adjustments to the old way of thinking and computing, but still, pretty straight forward....

Then you take a bicycle tire, where it should be pretty easy to come up where measurement points for labeling and purchasing, diameters, circumferences, & widths, pretty straight forward too, right? But, somewhere along the way, somehow, in the bicycle universe, 1 1/4" stopped equaling 1.25". And when that happens, yeah, I'm not ashamed to ask for a little help to make sure I'm not about to blow $40.

;)

I have an '86 Schwinn Traveler which was originally stocked with 27 inch wheels (and 27 X 1 1/8 tires). I was short a decent 27 inch tire once and still wanted to ride it, so I put a modern 700 wheel (with a 700 x 25 tire) on the front of the bike. With a slight adjustment, the brake pads fit and worked fine on the slightly smaller rim. I now favor this setup (27 x 1 1/8 tire on back, 700 x 25 tire on front) on this bike.

The 1 1/8ths fit perfectly. Bike looks & rides impeccably! Thanks again for your help guys....