How much difference is there between 700x28c and 700x23c tyres? Size wise? I have two hardly used spare 28’s sitting at home doing nothing and I need to replace my rear tyre. I can’t fit anything bigger than 23 on the front cause of fork clearance, but I’ll have no problem getting a 28 on the back. Will it be overly noticable whilst riding? I’m rocking a free 700x25c on the back and I can’t really notice anything, but i’m intrigued with even a bigger rear tyre.
It’ll be fine. It won’t feel like a hotrod or anything.
28s will feel a lot softer than 23s. But it also depends on what brand and model the tyres are.
eg. I’ve almost always used 23s. I tried Randonneur 28s and thought they felt heavy and sluggish. My cross bike has 30mm tandem tyres on it and they feel lighter and faster than the Randos did.
Also the measurements tend to be notional. ie. two 28mm tyres from different manufacturers will probably be different widths - and neither of them will necessarily measure 28mm.
i just binned some detonator 28s and swapped them for some gatorskin 23s. the 23s feel faster and slightly harder (ie less compliant). and i havent had a flat since i put em on, but thats more cos theyre a better tyre. i started running the 28s to avoid flats, but they totally sucked (avg 1 puncture every week and a half…).
im running 25s on my other bike, and theyre a real nice balance. once i wear out all my current tyres i think it’ll be gatorskin 25s all round.
sorry, back to original q. you wont notice much height/diameter difference front to rear… i was running 25 front and 23 rear and you couldnt tell.
Well that’s good to know. The 28’s are Michelins. I can’t remember what they are, I think they’re some standard “commuting” tyres, but they’re just sitting there doing nothing. When I did have them on another bike, swapping between that and the one I ride now with 23’s, the difference was huge, it was really sluggish. Hopefully it won’t affect my bike too much. with it on the back wheel.
Oh yeah, when I was in London my friend and I built up a polo bike for him 44x20 gearing, really raked fork, a 700c on the front… and a 26" wheel with a flip flop hub(!?) on the back!
5mm :-D.
No really, a 28 will be more ‘comfy’ but slower. Some 28s can tear your legs off when you skid. Etc.
I just want to use the tyres up. Maybe I’ll leave them for my girlfriends bike 
Girls loves 28’s.
Even her legs?
It’s like her own personal couch, armrests and all.
The difference is 5mm.
Recently repeated a 100km ride. The difference was 2 minutes - 3:01 on 23mm (10sp Record) and 3:03 on 25 front/28 rear (pre-1970s single speed) - and a smoother rider.
Put them on and try them. It only takes 10 min to swap a couple of tyres.
And what is the fat fetish around here?