Plexus

I'm biking down the pacific coast (Vancouver -> San Diego) and currently use 25c tires. I prefer to keep them on as I already have two spares for them and I'm already 30% under budget for the trip. I don't plan to go off road, but I guess it would be nice to be able to ride on some forest roads occasionally. I weight around 130 lbs and am carrying ~40 lbs of gear including water. Should I switch the tires or is it safe to keep using the 25s?

10 Wheels

You should be fine...Have a good tour.

sstorkel

I wouldn't want to use 700x25 tires on anything other than a paved road. In my experience, a higher-volume tire inflated to a lower pressure will give a noticeably more comfortable ride. 700x32 is the smallest tire I'll run on my touring bike when I'm carrying a load.

psy

..pothole + load + skinny tire = I don't even want to know.

acantor

I currently tour on 32 mm wide tires, but for more than a decade I used 25 mm and 23 mm tires. The wider tires feel more secure, and I don't get flats nearly as often. But during my skinny tire phase, I was oblivious to any problem, even when riding for short distances on gravel and dirt tracks. If your budget is limited and those are the tires you have, just go!

nun

The 25s should be ok. I'm 190lbs and carry around 20lbs of gear and use 25mm Continental Gatorskins. They are great on roads and on hard packed fire trails and paths. Avoid sand and soft stuff though. I rode the Erie Canal bike path on them last year and they worked just fine.

Rowan

Short answer is, for the riding you intend to do, even on the forest roads in that part of the world... you will be fine on 25s.

robow

You being a lightweight really helps but you are more likely to suffer from pinch flats with a smaller tire, and you won't have the stability nor will they be as forgiving to your rims as a wider tire. I have done more than my share of touring on what you're considering and though it will work, next time you might want to consider at least a 28. Enjoy!

B. Carfree

+1

I've ridden the section of the Pacific Coast from Eugene to Sonoma County too many times to count on 25 mm tires, and I outweigh you by 55 pounds.

hueyhoolihan

just did part of that route late last year on 700c x 28mm. i found nothing to complain about. at your weight 25s should be OK. OTOH it's not like there aren't plenty of bike shops along the way if you find what you have to be inadequate.

Doug64

+1

I've done quite a bit of touring on 25 mm tires, and a lot more on 28 mm tires. If you stay on the pavement, and an occasional gravel construction zone, you should be OK.

Machka 

I did a 3-month 5000 km full-loaded, self-supported tour of Australia on 23s and 25s. My route was mainly on paved roads, but covered some gravel as well. There were a couple places I could have wished I had slightly wider tires, but those occasions might have made up maybe about 3% of the trip.

I've also done tours in Europe with 23s or 25s, and have been just fine.

For what you're planning, you should be fine.

staehpj1

I rode the ST on 23mm half way and 25mm the rest. I weighed 190 but was packing very light. The tour included a lot of infamous Texas chipseal and some dirt and gravel. The ride was a little harsh, but OK. The roads where you will be are much better than a lot of what I rode on the ST. You should be fine.

Edited to note two things:
1. The tires I used were probably actually smaller than the rated size (gatorskins).
2. The buzz on the Texas chipseal was lessened a good bit when I went from 23mm to 25mm. Had it not been for the very rough surface on those Texas roads I don't think I would have noticed all that much difference between the 23mm and 25mm tires.

bradtx

Plexus, I've been experimenting with my distance roadie and the 25 mm tires haven't been a problem whatsoever and I weigh 180 lb. If you're using a roadie, I suggest moving some weight to the front and center using a handle bar bag and a frame bag. This seems to help keep my handling neutral.

Brad

andrewclaus

On my last tour I increased my tire size from 23 to 25 and I probably won't do that again. I could have saved the money and weight and the bike would have been fine, considering in 4500 miles I rode a total of maybe 25 miles off pavement. My total weight on the bike was about 175#.

bikemig 

Whether the OP will be fine on 25c tires and whether that is an optimal size for touring are two different questions. 32c tires (assuming the OP's bike can fit them) well be more secure esp. when coming down a mountain and will handle better offroad (the OP did say that he wanted to ride some fire roads). The rims will hold up better. The ride will be more comfortable with the lower pressure tires.

MassiveD

If your body thinks it is OK, should be fine. Of course racing norms have changed.

Tires: How Wide is too Wide? | Off The Beaten Path

mtnbud

It depends on your wheels and the condition of the roads. You'll be fine on pavement.

I once toasted a rear wheel on a tour after riding a 20 mile section on a gravel road using 25mm tires pumped up to 110 psi. The wheel might have been fine if I would have lowered the air pressure or rode more carefully.

I often broke spokes or came home with wheels out of true when using thin tires. I now use 32mm tires or wider and 36 hole Mavic A719 rims and haven't had a single problem. Coincidentally, I just rode a 9 mile section gravel road with a load near Florence and the wheels are still as true as the day I got them.

I'd avoid gravel roads to play it safe.

bikenh

I'm on tour/trip right now using 25cs and haven't had any kind of trouble with them. I do stick to pavement other than a couple small stretches on the Fox River Trail in NE Illinois that has pack gravel on it. The handled that packed gravel fine and I would do it again as long as the conditions are dry. I've been over plenty of potholes and I've had no trouble with the 35 pounds I'm carrying in the backpack and another 3-5 pounds of bike equipment I'm carrying in the handlebar bag.

fietsbob

Bene Sugg: bring an extra tire on tours ..

LeeG

28mm is still small for a loaded bike on forest roads. Being under budget 30% is a lot bigger chunk of change than a $35 tire. Go with what you got and make sure they are inflated correctly everyday.

dwmckee

I have done a 1000 mile tour on 700x25s and 30 pounds of gear. It gets the job done but you will have more flats. Not as comfy as 28s or 32s either. Why not get just one bigger tire and ride that. If it gets trashed replace t with the smaller tire. You will not notice the heavier tire weight or rolling resistance when carrying a load.
I hid a full sized brick when decending a giant hill into the fingerlakes and blew out both tires with pinch flats (double holes in both). Very scary and I could have been killed, but somehow no rim damage. Maybe 36 hole rims helped.

Like I said, you can do it, but better off with at least one bigger tire to start out on. I had about 2 miles on a dirt road and had another flat less than a hundred yards in.

staehpj1

Different strokes, but I did the opposite. I started the Southern Tier on 23mm tires and put on 25mm tires when they wore out. I am usually inclined to wear out what I have before replacing. At one time I believed in starting tours with fresh new tires, but I found that once I take them off I never use them again. I decided that was a waste of expensive tires and replacing worn tires in the middle of a tour isn't a big deal.

I'd say start with the skinny ones you have and if you wear them out or hate the ride, replace them with whatever size makes sense to you at the time.

Boudicca

I'd question the 40lbs of gear as much as the 25mm tires. You really want to lug 40lbs of gear up and down hills, not to mention forest roads? Can you cut that down?

dwmckee

I have to agree that there never is a shortage of diverse opinions on here. For me though the number of flats I had on 25s was a hassle big enough to warrant starting on a bigger tire if I had the option. my ride at the time just did not have room for anything bigger than a 25. Flats not only are a hassle but can be dangerous at the wrong moments especially loaded. I have never had a flat cause an accident but I have had a couple that required some nimble steering to prevent one.