riding with different size tyres

If you really need to get that front tire off, Soma Fabrications makes steel cored tire levers. There's no problem with riding two different sized tires. Since most of your weight is on the rear tire, it makes sense. A lot of pros do it on rougher courses like Paris-Roubaix. Also, the Continental Attack/Force tire set has a slightly wider rear than front.

Future-pro said:

well i put on some michelin 700 x 23 tyres on by road bike only to find that there was a cut in the side wall of the rear tyre so ive changed back to a 700 x 25 now my problem is im having difficulty taking the 700 x 23 tyre of my front wheel so now ive got a 700 x25 at the back and a 700 x 23 at the front will this have any effect on the way the bike rides and does anyone now a way of taking a tight tyre off ive already broken two tyre levers on it

I do the same thing but on purpose but I use a 25 up front and a 28 in back. It makes for a more comfy ride and (at least in theory) there's more rubber in a larger tire so it should last longer, provided they don't get cut by road debris.

Doctor Morbius said:

I do the same thing but on purpose but I use a 25 up front and a 28 in back. It makes for a more comfy ride and (at least in theory) there's more rubber in a larger tire so it should last longer, provided they don't get cut by road debris.

And there's the other way; riding with a wider tire up front for better traction in cornering to prevent washouts.

Future-pro said:

well i put on some michelin 700 x 23 tyres on by road bike only to find that there was a cut in the side wall of the rear tyre so ive changed back to a 700 x 25 now my problem is im having difficulty taking the 700 x 23 tyre of my front wheel so now ive got a 700 x25 at the back and a 700 x 23 at the front will this have any effect on the way the bike rides and does anyone now a way of taking a tight tyre off ive already broken two tyre levers on it

Don't ride with one crossply and one radial.

I've never had the problem you're having with removal of a tire, but try applying a 50/50 mixture of water and liquid dish washing detergent to the bead and the rim edge and see if this helps. A small amount of this helps me get stubborn tires on every time.

Some tyres sets are different sizes / tread patterns deliberately so its no real problem at all.

Cheers

Larger tyres have less rolling resistance, but more air resistance if that's any help. Other way round for smaller tyres.

Bill.

Some of the early time trial bikes had a smaller tire in the front, and a lot of recumbent bikes do. Shouldn't be a problem - just tell everyone you're training for time trials.

I had a problem with tire irons breaking - those plastic ones. Replaced them with a set of metal Park tire irons. They don't break.