StephenH

Speaking of spares...and spare frames...
Consider:
Spare shift cable (buy tandem-length, and it'll fit regular single bike or tandem or recumbent)
Spare pump/inflator
Spare spoke or two (Fiberfix, for example)
Patch kit and spare patch kit- and rotate them, the glue will dry out even if the tube's never been opened.
Quick-links to fit your chain
Chain tool
Spare cleat and spare cleat screws
That's all pretty small stuff. I've had the broken pump, dried patch kit, broken chain problems. I've seen the broken shift cable, broken spokes, and broken cleat or missing screw problems.

Carbonfiberboy 

I had a shift cable problem on a recent tandem ride. I do carry a spare cable, but not the stupid tiny Phillips screwdriver needed to change the cable on Shimano 10sp. brifters. Another thing for me to add. We made it back OK anyway.

unterhausen

I carry a spare tube for 25mm tires because people that use that size seem to need them more often and they are weight weenies, so they only have one tube. Silly, I know, but I was riding with someone that had a double flat and I felt bad I didn't have a tube to give them. I have given one away so far. But no, I'm not carrying a spare 25mm tire

ThermionicScott 

I recently added a 700x23-25 tube to my handlebar bag for the same reason. I figure it'll be good karma.

Cyril 

Yes. I carry a spare tire. Sometimes brand new, sometimes slightly worn.
I've had a couple of occasions to use it myself ... and I've bailed out fellow randonneurs.
Slightly OT: After spending FAR too much time trying to find the cause of a mystery flat on a 200km,
I've started carrying rim tape. And it has seen some use.

Cyril

ReneV

For 400k and up in remote areas, I use a Topeak Tri-Backup Tirebag. It's made for a tubular but takes a clincher, two tubes, and tools. And, a decent-sized pump on the outside.

Folding technique: push one half into the other; repeat a few times; wrap in cling film.

EDIT: a worn 25c GP4000sII.

wipekitty

I've been known to carry a spare tire, especially if I'm planning to ride solo for extended periods of time. I have a GP4000SII that's in decent shape but has a few thousand miles on it; it's folded up and ready to go in my box of bike stuff.

rhm

I'm somewhat curious about the popularity of various wheel sizes on randonnees. I'm sure 700c is the most popular size, probably followed by 650b, but after that I'm not sure at all. I've used other 26" sizes (650a and 559) but I can't recall seeing anyone else using those. Recumbents often have one or the other 20" sizes. Someone might still be on 27" tires, but I rather doubt it.

What would that be statistically? 700c over 80%, 650b over 15%, maybe? Has anyone seen quantified studies?

Anyway, apropos this thread, people using 700c tires can pretty safely assume there's another rider with a spare tire, and 650b riders can make that assumption a little less confidently. Anyone else better carry a spare.

Spoonrobot 

unterhausen

I don't think you are going to find a spare 650b tire on a randonnee. I wouldn't count on it anyway. I ordered some 38mm 650b tires by mistake, I intend to use one of them as a spare for the 44mm tires I'm using on the bike.

79pmooney

Folding tires make this child's play. For wired beads, the trick is to hold the tire in front of you like a hula hoop you are about to lower and step into. Twist the tire 1/2 turn with one hand so it forms a small loop (1/3 of the whole tire). Now twist the large leftover loop so it forms two equal loops. Fold the loop you are holding onto over so it lays on top of the second loop. Now fold both of these over the first loop. A zip tie at the hand you never moved will hold the whole package. (This coil will not fit under the seat cluster. That comment was meant for folding tires.)

Ben (who brings home all his new wired Paselas in his panniers)

bikemig 

You have just tempted the cycling gods but then you knew that . . .

ThermionicScott 

Maybe I like to live on the edge! I did ride a 650A bike on PBP 2015 -- wonder if I was the only one to do that, and if any bike shops in all of France would have that size in stock.

rhm

Oh, they have those in France, don't they? I thought it was common across Europe, certainly anywhere where a Raleigh could be bought (i.e. anywhere).

ThermionicScott 

I guess I don't actually know. I figured 650A wouldn't have gotten as much of a foothold in France, between 650B in the early years, and 700C after that.

unterhausen

during PBP, you're probably stuck for tires or wheels if you don't have a 700c bike. I know two people that had wheels replaced in 2011, and I thought about it. Main thing that stopped me (other than the fact that I was still rolling) was the amount of time the control bike shops take to do a job like that. Couple of hours to replace a wheel.

yannisg

I don't carry an extra tire on any of the brevets (even 1000k). I have had cuts on the sidewall and tread which are the worst because the patch keeps rubbing on the ground and fails. I have used bills for the sidewall that hold up, but get worn after a few klm if used on the tread. I have used the Park tool tire patch that didn't fair much better on the tread. The best solution I have found for cuts on the tread is a piece of juice carton (tetrapack). They hold up much better than the Park tool tire patch or a bill. Last year I completed a 200k brevet with the carton patch in the cut tread for 100k. I carry pre-cut pieces on all my rides whether training or Brevets.

az_cyclist

I carry a spare tire for the double centuries I ride in California (the California Triple Crown series) . that is partially because I dont want to drive all that way over to the ride, and DNF because of a sliced tire.

ThermionicScott 

Post-script: I just got back from this year's RAGBRAI (a 7-day, 400+ mile tour from one side of Iowa to the other, for those not familiar), and on the first day(!) had an opportunity to give said 700C tube to a rider in need. Meanwhile, my 650B tires didn't even need pumping the whole time.

atwl77

I brought a spare tire for my 600k brevet, but not for last week's 400k -- bike loadout was different, I didn't have enough space unless I carried my larger seat packs which only happens if I need to bring extra change of clothes (i.e. 600k and above).

But on last weekend's 400k, one of the riders I was with had a cut in the sidewall right in front of me. I heard the pop, saw a large stone fly away, and her front tire was instantly flat. We still managed to patch the tire and continue... but I guess in those instances a spare tire would have been a lot better. Although I have to comment, I see a lot of people ride these Continental GP4000 tires with weak sidewalls on brevets (ok, not sure about where you guys ride, just commenting on my own region and experiences). Why ride those racing tires on long distance brevets? I get that they are extremely popular due to supposed durability (I haven't seen it -- I keep seeing people flatting with them in both brevets and sportives/races) and great rolling resistance (can't argue about that one)... but personally I'd rather minimize flats than have to deal with them. Especially on brevets where night riding in remote regions is a thing...

Tourist in MSN

About a week ago I suddenly realized that I had a big bulge in the front tire on one of my bikes. Based on tread depth, that tire had been used for less than half of its lifespan. Fortunately I was home at the time, that tire was changed within an hour of seeing the bulge. I suspect I hit a bump too hard and tore some of the fabric in it.

WrenchSpinnr

xcallibre10

agreed

znomit

Yes, if you know where to put it. At 3am. In the rain.

unterhausen

not only that, say you have 100+ miles still to go in the dark in the rain. Do you really want some kind of lash-up tire hack keeping you from a face-plant? Sure, if you're 20 miles from home or it's the only way to avoid ubering, but a tire is a much better solution.