what’s the consensus? 25 or 28?
25 in the front, 28 in the back?
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what’s the consensus? 25 or 28?
25 in the front, 28 in the back?
Viewing 15 replies - 1 through 15 (of 25 total)
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What would Sir-Mix-Alot run on his bike?
As big as will fit in both places, we are on backroads that may or may not have repairs made with bicycles in mind. There will be large potholes and cracks that will attempt to eat your tire and not let you out of the groove. Hazards just appear from underneath and between other peoples bikes on Ragbrai so dodge and brace for impact time is sometimes non-existent. Anything that eats some of the “buzz” of the road is what you want for a ride of this length.
Skinny tires are not faster when it comes to rolling resistance and by the time tire width matters aerodynamically you need your, time trial wheels, teardrop helmet and shoecovers anyway. Go for the most long haul comfort your frame will fit. Skinny is not dangerous it is just less than ideal in my opinion for this type of ride.
Even white boys got to shout!
23s worked fine for me. I switched to 25s for the 1st gravel loop 2 years ago.
The road hazard to be careful of is on concrete roads. There are expansion cracks between the lanes that a thinner tire can stick in if you don’t cut across the crack fast enough.
I have run 50 or 100mm for the past 5 years. It works well, but I will admit: I have not won a single stage since I switched to bigger tires.
Andy…you have made me laugh! I haven’t won any races on my Schwalbe Marathon Plus tires either…problem is likely with my wide spare tire and not my road tire. We are a Schwalbe family for the most part.
RIDE RIGHT a 28 or 35 mm suits me fine.
Every single mile I have ever ridden at RAGBRAI has been on 38mm Vittoria Voyager Hypers. Technically my first set went by a different name but same tire and width. My bike frame could run at least 45’s and if Vittoria or someone else made an efficient 45 I’d be running those instead. I don’t know if I finish each stage ahead of or behind Andy!
Mathew, I run on Continental 25mm Gatorskins. I have over 2000 miles on Iowa roads and have yet to have a flat.
My experience, the wider the high pressure road tire, the incidence of a flat increases!
My experience is the same. On 23s I got far fewer flats than on 25s. I’m sure many on the real thick and much wider tires don’t have issues. It seems to be the high performance lighter, thinner tires the wider tires get flats more often. Makes sense, wider means an increased chance of running over that chunk of glass.
All I can tell you is that in five years of running 38s, roughly 12k miles, I’ve had one puncture and then a secondary puncture that seems to have been caused by the rough edges of the hole in the tire casing from the first puncture wearing through the tube! A tube patch applied on the inside of the tire casing over that hole fixed that. Yeah, statistically speaking, if my tires are twice as wide as yours I have twice the probability of meeting that piece of glass but punctures are rare enough for 23s that even if they were half as rare they still would not be much of an issue. If you switch from 23s to something wider and see your puncture rate increasing by more than the ratio of widths then you are just having a spell of bad luck! I spend a lot more time waiting for kybos and showers than I do fixing tires at RAGBRAI so life is good! And then there is the fact that my twice as wide tire is half as likely to be bothered by that crack in the road to consider….
Since most of the people I see at RAGBRAI are riding 23s most of the people I see fixing punctures at RAGBRAI are fixing 23s. Puncture statistics are quite maddening no matter what tires you run. I remember seeing someone fixing a puncture less than three miles from the dip site the last time we started in Sioux City. That has to be discouraging but I doubt they had to fix another all week.
From a weight bearing standpoint running a wide tire on back and a narrow one on front makes sense. I suspect a lot of people with my body mass and more would be better served by a 25 or even 28 on the rear because they would be more efficient at the loading they are going to see. On the other hand if you are going to use wider tires the existence of those road cracks and other hazards suggests that you want a wide tire on your steering wheel too.
But real men and real women have no trouble riding even the gravel loop on 23s so do what you like!
I don’t get more flats with wider tires – but not less either. Maybe one or two a year.
I would expect a rider to get more flats on a wider tire IF the tire pressure is not reduced to account for the larger air volume. If you are putting the same psi in 25 or 28mm tires as you use in 23mm then the casing will be stretched tighter. The more taut the casing, the easier it is going to be for something to pierce through and give you a flat.
I reduced my air pressure and still got a bunch more flats on 25s then 23s. The wider the width of the contact patch, the higher the odds of hitting a chunk of glass squarely enough the result is a puncture no matter what the pressure. But the hype about wider tires actually being less likely to flat I think is about the tires that have thicker rubber like gravel tires.
And if you go tubeless, it eliminates the chance of a pinch flat which is nice. More futzing around if you do flat though.
I have rode with 23 and 25. Air them to the max and have had one flat in eight years on Ragbrai. I rode through the area where the kids had thrown out tacks and didn’t get a flat. I remember going around the street sweeper that morning and thinking, what a crazy time to schedule to clean the road. I had no knowledge why they were doing that till the end of the day and everyone was talking about all the flats. My suggestion is ride on what you normally do, and enjoy the ride.
Rider weight and tire pressure, along with how much of the 23, 25 or 28 size tire meets the road has a significant impact on flats. I suspect there are many less flats on 38’s as they carry much less pressure and are much thicker and often have more tread than a true road bike tire. Sorry, but there is no way a 38 fits on my bike. I know this is weird, but I’ve never had a flat on the 4″ tires on my fatty.
While we’ve taken it for granted that high tire pressure will result in lower rolling resistance, it turns out that’s only true under laboratory conditions. New research is showing that in the real world, lower tire pressures are actually more efficient – and of course, much more comfortable.
The hyperlink below is to an interesting short article that in turn links to a longer and much more interesting podcast on optimal rim/tire size and tire pressure (featuring Josh Poertner, former tech director at Zipp, now owner of Silca, and Jan Heine of Bicycle Quarterly) Panel Discussion: The Wide Tire Revolution
When I got a new wheelset last year with Archetype rims (17mm), I took the advice from the Bicycle Quarterly piece and ran my 23mm Contis (which actually measure about 24.5mm when mounted) at about 70 lbs. I can’t measure efficiency but can say that I now have a much more comfortable ride. No flats in the roughly 18 months and perhaps 2,000 miles I’ve run the combo on the crappy roads here in PA either. A caution before trying this on stock rims (which are generally pretty narrow, usually no more than 15mm) You can run at lower pressures but will face an increased risk of pinch flats.
YMMV but the podcast is worth watching/listening.
The Vittorias I am running are NOT inefficient, “bulletproof” tires. They are essentially a 38mm touring version of a mid grade racing tire. Last time I checked, perhaps a year ago, they were the most efficient touring tire known to man. So I am making the intentional choice to expose myself to the greatest risk of punctures that tires of my chosen width will see in the real world. In the name of efficiency. No one who rides the same roads and trails as I ride on 38mm tires will see a higher puncture rate than me!
We are never going to sort out the truth about how tire pressure and width affect puncture rates in the real world by sharing and pooling our anecdotal stories. The fact that some of us have ridden a particular type of tire in the real world for an extended period of time definitely does say something about what the puncture rate of that particular tire is under the conditions we ride in. It is real data. But our collective experience is not a controlled experiment and we cannot therefore draw from it all the conclusions we would like to have from a valid scientific study.
And if your story is that I was using this kind of tire for a long time with no punctures, then tried that kind of tire and had 3 in six months so I went back to my old kind and had none since? Well, it is an interesting story and potentially significant. Since you did not stick with that second type of tire for a long enough time to get a good read on it your experience really isn’t a data point. It merely highlights something that needs further study.
With 10k-25k riders all taking the same route, on the same day, for a significant number of miles RAGBRAI would make a good place to do a real scientific study of all the issues that affect puncture rates in the real world. But how much would the study sponsor have to pay some of you to ride something other than your beloved 23s? Aye, there’s the rub, there’s not enough money in the whole wide world!!