ppg677

My old steel Trek 957 frame hardly has any clearance between the wheel and the seat tube. With 23mm tires I've only got a few mm clearance with the derailleur bracket.

I'm a bigger dude...220 lbs. I've been riding this with 23s for the last 5 years. Just blew the sidewall in a newer GP5000 so time to buy new tires anyways.

I'd go 25mm tires if I knew I still had clearance.

Anyone know or recommend a 25mm tire that only gets wider and not much taller?

cxwrench

Good of you to provide a massive close-up photo. Too bad it's from such an angle we can't tell a damn thing about tire clearance.

Iride01 

No, typically I expect bicycle tire dimensions to increase the same in over all diameter as the change in width.

Why did your sidewall blow out? At 220 lbs you aren't an issue for bike tires. So perhaps you run too low a pressure or way to high a pressure. Usually low PSI will be snake bites, but damage to the tire casing can be an issue too if the tube is lucky enough to stay out of the way.

ppg677

First flat in at least a couple thousand miles so I've been lucky and haven't had issues. I probably hit something. I assume a punctured sidewall should be replaced.

Iride01 

Depends. Lot of personal preference involved too.

I've never had a wreck from a tire failure no matter the speed I was doing. I could always slow down and stop safely. Maybe one day....

For any puncture, including sidewall punctures, the deciding factor for me is how much does the area around the puncture pooch out when the tube is inflated to proper riding pressure. If it's much of any pooch, then the tire is getting replaced. But I certainly will ride it home like that, though I'd probably boot it. And if I didn't have a tire in stock at home, I'd continue to ride until I obtained one.

But I might not plan on doing a century ride or try to best my downhill segment times on that tire.

ppg677

I've had several flats while road riding (just not in the past couple years...yeah, I'm only ~1k miles/year).
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This one went very quick. If I was bombing 45 mph on a downhill I would have been in trouble.

shelbyfv

Such a pretty bike! Have you considered a 650b conversion?

ppg677

Definitely not! It's a 60mm frame and handles well. A little twitchy from the short wheelbase.

tempocyclist

If you had 23mm GP5000 tyres in there, you might be able to fit 25's from another brand. The Conti's tend to measure up wider than most.

Branko D

I just don't see anything bigger fitting, that's a really close fit.

ppg677

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I'm gonna try a Pirelli 24mm P ZERO.

Iride01 

Did you determine why you flatted? If you don't do any forensics on your flats then you'll probably be swapping tires a lot. Few of my flats are actually from road hazards.

ppg677

I rarely flat. When I do, I look for the cause.

In this case, I didn't find the cause but I think I went over a sharp rock angled in a way to puncture the sidewall.

I'm not looking to move to 25mm for more flat resistance. Mainly for more comfort.

Kimmo 

Isn't the FD clamp what will hit first? You can get a low profile clamp like this:


Might add a bit of flex that hurts the front shifting though.

ppg677

Wow, interesting product. Crazy expensive at $95. But yeah, I may have to check that out.

Kimmo 

I found one a few years ago for like $30, the brand was Cutter.

Still got a bit of the packaging, cause it says, if this thing sucks, send it back. Thought that was pretty cool

Sy Reene

I was going to suggest searching around the stats on BRR, they provide measured height and width numbers and their tested tires for road are typically always 25mm labelled.
eg. https://www.bicyclerollingresistance...orsa-graphene2

Road Fan

I agree! What the OP can do is measure the width of the existing tires and post up a question, "what tire will give me about a millimeter or two more tire/seat tube clearance than this tire, regardless of actual marked size?"

Might also consider having a front deraileur braze-on mount added, to eliminate the issue with the thickness of the clamp. Another thing to consider is that Trek may have intended this lightweight beauty to be set up with 20 to 22 mm tubular tires in the 240 gram or less class. That is a very tightly-built frame!

Litespud

not to hijack the thread, but what shifters are those? They look like 11sp, but I thought all 11sp shifters had black levers

ppg677

2016 Campagnolo Athena 11-speed. I went for the pretty silver look... probably their last year of silver. Mistake as I would not recommend after 4 years of riding (perhaps 1k miles/year)

The left shifter came apart on me. Bike shop (very experienced with Campagnolo) wanted to replace but couldn't find the part. I managed to get it back together even though an internal plastic part was slightly deformed. I'm not expecting it to last much longer.

Litespud

too bad about the longevity, because they look great

oxman

I thought that I had read on this site numerous times that Campagnolo typically offers individual replacement parts. I am not doubting you of course, just asking.

I really like the silver finish of your group-set. Very sharp looking bicycle too.

Kimmo 

Wasn't there a silver Potenza group not long ago?

ppg677

Follow-up on Tires: turns out a 23mm GP4000 tire actually measures 25mm with my calipers. I installed a Pirelli P Zero 24mm tire and it measured exactly 24mm in width.

njkayaker

A wider rim should make the overall diameter a bit smaller.