Sitting out drinking wine and looking at my "old" road bike today. It's a circa 1999 Specialized Allez Sport. I never have ridden it much as its just not comfortable, but I noticed today that the rear tire is a 700x25c, and the front is a 700x23c. Anybody else riding on 2 different size tires? I have been doing that for about 3000 miles on that bike. As the sole owner, it came that way too!

It took you 9 years to notice the size difference?

I've never done it before, but I have a few friends who have different size tires, front and rear.

Look at the Continental Attack/Force pair.

I'll notice an anomaly on a bike but not on most other things. Cars and houses can be really screwed up and I'll never know the difference, but a bike...I'm all over it.

Everything is skewed on 'bents: Mine have 20x1.35/20x1.5 and 20x1.5/26x1.5. (Don't see mismatched wheels on upright bikes much, do you?)

Well, he's never drank wine while pondering his bike I'd guess. Some wine does amazing things for your pondering abilities.....

I mounted up a 23 front and 25 rear on my new Redline SS. But I did it knowingly since these were the two tires that were fronts up to recently and were not all worn and cut up from being rears. See my post in Commuting on the ratio of front to rear flats to know how I ended up with two odd sized "fronts" on this bike. The old rear tires looked like jungle animals had been gnawing on them from the number of cuts and tears.....

Oh, and the bike is riding just fine with this combo. It's only a silly 2 mm's after all.

Yes, to the 25/23 setup. Claimed fewer flats as most flats seem to be on the rear wheel. Also Conti Attack/Force tires are different widths front & rear.

I would just stop drinking or change brands 'cause ignorance is bliss.
Now the size difference will bug you forever.

Sounds like you get to always ride downhill with that combination. Me likey.

28 rear, 25 front. Also been known to run 25 r and 23 f.
Sometimes it's not a planned event but since I have a couple of spare wheelsets they may get intermixed with different tire sizes.
Rigid mtb has different tires front and rear.

Going back to mountain bikes- 15 to 20 years ago it was normal to run different size tyres. But the larger tyre was on the front. Supposedly this was to give better steering. That may work in the "Dry" winters of the US (There must be some bits that don't have too much winter rain)- but over here wide tyres do not work in mud. They skate over the surface of the gloop offering no grip and if I was going to lose traction, I always felt it was better to lose the rear tyre.

Given that there are mountain bikes that have a 29" front wheel and 26" rear wheel, and many recumbents have have 16" on the front & 20" on the back or 20" on the front and 26" on the rear, I don't think your 2mm tire difference is much to be concerned about.

Stapfam, I seem to remember that too but it was in relation to sand as I recall. The wider tire floated over it easier and the rear didn't matter if it dragged its way through as long as it stayed behind the front end.

Around here the Shore guys use 26 fronts with around 2.35 to 2.5 inch and on the rear they like to go with 24's mouting 3.0 to 3.5 if they can shoehorn them into the rear frame area without rubbing. But they do it more for the impact absorbing on the bumps and only partly to lay back the steering angle for a little more stability when shooting down A line at Whistler (think of this as like falling off a mountain but riding a bike while doing so.... )

Funnily enough I thought of sand as one of the possibilities of running a wide tyre on the front- but we don't have much of that over here. And sand would be a reason to run a wide tyre.

Staying on MTB's- I have always found it beneficial to use a tyre as narrow as possible. Less drag on the hardpack we have in summer and provided the tyre has enough knobbles on it- it will get enough grip in the gloop that gets on the trails in winter. This is dependant on ride comfort aswell- but there is a compromise between rider weight- comfort and width of tyre.

I am a lightweight at 150lbs so can run a narrower tyre than taller- well proportioned riders. I have carried over my MTB experience onto the road and use 23's as my only width of tyre. Roll well enough- have durability and do not cause me discomfort. However on a stiffer frame- I can see the reason for a wider tyre- even though I would not have to use one. But I also feel that if you feel the need to run a wider tyre on the rear of a bike-then you might aswell run the same size on the front. Main reason would be Rider weight being distributed evenly on the bike- but it also means that I only carry one spare tyre in my stock for the 3 road bikes I ride.

My girls used to tell me I was clueless...until they got old enough to know I was right all along.

For many years I ran a 23 on the rear and a 20 on the front, with no real problems and in fact still have two of my bikes set up that way.

On the two I ride most, however, I've gone back to 23's front and rear, just so I don't have to change so many tires around, so often, i.e. a slightly used rear becomes the front and the new tire always goes on the rear (but hey, that's just me).

Rick / OCRR

I am clued in about my tires and they match. But as for the rest of life...:/

To answer the titular question, I'd have to say yes. Mostly on a daily basis...

But my tires match. Is that a wash?

The original Continental GP Attack 700x22 front; GP Force 700x23 rear came only as a set. I liked them but I'm not sure that 1 mm made all the difference. Then again I've been clueless all my life - why change now?!


For you really over 50's, you might remember a cigarette that advertised itself as "a silly millimeter longer"...

Sorta remember that. But I do know what LSMFT means.

And I thought the thread title was

Ever been totally useless?

And the response, of course, would have been

Yes, all the time!

Chesterfield 101's ?

Benson and Hedges (if I spelled it right.) "America's favorite cigarette break" was one of their ad campaigns, which featured, among others, the semi-famous 'dismembered glove' hockey ad.