advice on road bike tires
 

hi there
I am wondering if there would be much difference between Schwalbe Marathon Plus 700 x 32c vs the 28c version ?
in terms of speed, comfort, grip, and most importantly puncture resistance ?

Some details below,

I have a ribble Titanium road bike with Schwalbe Marathon Plus 700 x 32c
I ride in the uk mostly on back country roads in Scotland all year - some really smooth, some quite bumpy - but not off road
I dont do massive rides - max around 100km / week
I really dont mind too much about speed / pace, my priority is puncture resistance (primarily) and also comfort and grip. However i would like to go faster/ futher if i can!

I am wondering if i drop from the 32 to for example a 28c - what would the effect be on speed, comfort, grip, and most importantly puncture resistance ?

any advice welcome!

I suspect it’s a lateral move in puncture resistance. Narrow may feel a bit more sporty.

I don't think you'll feel much different on the 28s.

My advice would be to try it and find out for yourself. Often, moving up or down one size makes almost no difference at all... until it does. That point, and whether the difference is a good thing or not, is going to be different for everybody, and you'll just have to experience it for yourself.

maybe 25c ??

You'll only know for sure if you try. I'm still riding on 25's. And I've been on some pretty bumpy roads. If I rode bumpy roads all the time I might switch to 28's. Though I have been wondering why everyone thinks wider is so great, so I might just try them for that.

The big picture here is that I'm going to try them, not that I'm asking for someone else to tell me what to do!

Maybe. They'll be lighter but they may feel worse due to less volume and higher pressure. The thing with tires (as with everything), it's all a compromise of one aspect vs. another. Marathons (of any width) are very long lasting and provide excellent flat protection, which is why they are so popular with tourers and commuters. They are also heavy and slow feeling compared to a supple racing tire, so you don't usually see them on race bikes.

If you want fast and supple, you'd choose something like a Continental GP 5000 or Vittoria Corsa. I think you'd really feel the difference there, but you won't have the flat protection of the Marathons.

It’s just physics, but in theory the 28c will have less grip and you’ll have to run these at slightly higher pressure so also slightly less comfortable. But the difference will be very small, and maybe not even noticeable. Also, if you switch manufacturers there might not even be a physical difference as they all seem to have different ideas about what size means. I have 28c Continentals on one bike and they measure 30.6mm at the widest and I hade some 32c Vittorias (exact same rim) on another bike and these measure 30.2mm at the widest. Go figure.

Not an answer to your question, but most cyclists (me included) have ‘gear acquisition syndrome’ really bad. One of the symptoms is getting an idea in your head that if I just bought a new thingabob for my bike my riding would be sooooo much better, but that’s generally not the case and it’s better to ride what you have into the ground until it’s time to replace it.

If puncture resistance is most important, you'd be best advised to get a tyre model that specialises in that through additional layers designed to do just that. You will trade off rolling resistance, but you can't have it all.

In terms of width, it really depends on the roads, weight of the rider, and desired comfort levels, once you found the right model. One option to explore, which is not talked about very often, is a narrower, higher pressure tyre up front and a wider, lower pressure tyre on the rear. That way in terms of speed you'll have a slight aero advantage, particularly if your have aero wheels with narrower diameter, but still more cushioning under your seat, with less aero penalty given it's on the rear. I like a more edgy front feel that transmits road characteristics, but a mellower rear that absorbs bumps under your seat.

I went from 28 to 30 and then to 32 and the only difference I can tell is the wider tires (with lower pressure) are more comfortable. I ride lots of bad pavement and lousy chip seal so the improvement is very noticeable. I can't imagine going back to a narrower tire now. Note that I don't race and I'm not obsessed with chasing speed goals.

Out of the box suggestion would be to switch to tubeless with 32mm Continental GP 5000 S TRs. You'll see a massive reduction in rolling resistance and tubeless sealant will handle most punctures without you needing to do anything.

not to derail, but are the very cheap tires (some are sub 20 at Sports Basement, a store like Dicks) suitable? everyone tells me to just get some gp5000s but I need some new tires for a couple bikes and want to go the cheap route. How cheap is too cheap?

OP I dont think there is any inherent difference in terms of puncture resistance as long as you have enough pressure.

Cheap tyres are not often discussed on the forums, as everybody seem to just recommend the most elite stuff they can think of. Im sure there are some perfectly serviceable cheap tyres out there and a lot of garbage. Personal experience with Wiggle own brand "lifeline prime" is they are fine. Both the the Armour and the Race variant. I also tried some Michelin Litheons, that was very flat prone and quickly retired. Lately I've been running Pirelli Velo, that was very expensive. They ride fine too, but the difference to the Lifeline I ran before is not that big, even if I can notice it. I would always look for some flat protection, no matter if its cheap or expensive.

I doubt you will notice any speed difference going from 32 to 28 on the same tyre variant. Likewise with puncture resistance and grip. The only thing you probably will notice is a loss in ride comfort. 32 to 28 is quite a significant decrease in air volume. What's your motivation for trying narrower tyres? Given the priorities you listed (especially comfort) I would stick with 32c. But if it's a supply issue then 28c are not going to feel that much different. I wouldn't bother with 25c on mixed uk roads. Those will just make your bike feel less compliant on the rougher road surfaces for no obvious gain in speed. Indeed they could well be slower.