Jamesrigby

Hi, my bike rims are 622*15c and i currently have 622*23 (700) tires. I am planning to do a coast to coast which may include some off road...

What sort of tires would you suggest?
what are the largest tires the rims can take?

Thanks

Maelochs

Ummmmm ..... no way to know what your rims can fit because you never mentioned rims .... but if your rims were designed for 15-mm tires, which as far as I know are not even produced or used (except in C&V-land) then your wheels are probably old and tired and need replacing.

If you mean your wheels have 15-mm internal width, you should have no trouble fitting 28s, assuming the 28s clear the frame. I would not want to do much off-road with 28s .... but "offroad" is not a definition it is a description. Rock-hard baked mud, no problem. Sand, loose gravel, pea gravel, single-track? Game trails? Pastureland?

I suggest tires built to ride the terrain you plan to ride. No idea what that is.

I have done supported coast-to-coast, on pavement, on 23s ...... but all the gear was on a vehicle and all the roads were paved. And a few times i wished for wider, softer rubber .... chip-seal is brutal. On the same ride I used a second bike with 32s and it was much better. I also did a south-north tour, fully loaded, on 32s and again exclusively on pavement. No problem.

Maelochs

Feel free to tell us more about the bike, the route, your cycling experience, your ideas of fun on a bike ... whatever.

Jamesrigby

Sorry made a mistake. Yes i meant 15c internal frames on a boardman 2018.

Would 28 be the max?

There might be paving/gravel and the odd muddy path i.e canal path. Its Carlisle to Newcastle, hopefully not too extreme, but i dont want to damage the wheels. I won't be doing things like forest trails.

So more grip/comfort/less likely to damage wheels it the idea

alcjphil

This is how misunderstandings happen. You mentioned a coast to coast ride without mentioning which country you live in. I live in Canada. A coast to coast ride here is much different than a coast to coast in the UK. Included information is important

Jamesrigby

Thats fine. Mainly looking to tire sizes I can use...would 32 fit for example?

alcjphil

They might be a bit wide for the rim, but the bigger question is whether you have sufficient frame clearance. You mention a 2018 Boardman bike but no mention of the model or type of bike it is

noimagination

Whether a certain size tire will fit on the rim is one thing. Whether the fork and/or chain stay/seat tube clearance is sufficient to accommodate that size tire is something else.

I see Boardman bikes, but I don't see a 2018 model. If that is a model year, then you need to provide info on the model, since Boardman seems to make a full line of bikes (road/racing, hybrid/commuting, mountain). If you don't have specs on clearance for tires for your particular model (some manufacturers will give info on what size tires are appropriate for certain models, but many don't), then your best bet is to bring your bike to a bike shop and get their advice. Unless you can find someone in this forum with your bike or a very similar one, it will be very hard for any forumite to give you definitive answers. .

What brand and model of tires do you have on the bike now? How much clearance is there between the current tire and the fork (crown and blades)? How much clearance is there between the tire and the seat stays at the narrowest point, and between the tire and the seat tube? Given that info, you might get someone willing to give advice on how much bigger you might be able to go.

Also, if you're fitting fenders on your bike for your tour, be aware that will affect the clearance, and may force you to use a smaller tire.

icemilkcoffee 

32mm tires are fine for the rims. The only potential issue with a fat tire on a narrow rim is that it's more of a struggle to get it past the brake pads when you are removing the wheel from the bike.

KerryIrons

Quit using the "c" reference - it makes no sense. Your rims are probably 15 mm inside width. Frame clearance is the issue that will likely limit your tire width. Of course a wider tire would fit better on a wider rim, but lots of people have ridden lots of miles on wider tires and narrower rims. There is not really an "upper limit" that you need to worry about.

Iride01 

IMO, 622x15c is a appropriate way to describe a rim size. It lets me know that it has a BSD of 622mm and a internal width of 15mm and is a crochet or hooked rim.

So how that confused anyone I don't know. Though it would be nice to know if you are also talking about aero rims that have a profile or just plain rims, which is what I'd assume since you didn't give that information.

Welcome to BF.

As you can see, just like we all have *******s we all have opinions too!

VegasTriker

The go-to chart for determining which width tires will fit a particular rim can be found at the late Sheldon Brown's website https://www.sheldonbrown.com/tire-sizing.html. Scroll down until you see the chart in red and green. This tells you which tire widths are safe with your existing rim. As others have already said, then you need to know how much room is available on the front fork and rear part of the frame. What might be safe might not fit inside the frame or between the brakes if it has rim brakes.

SpedFast

Welcome to the forum.

big john

I've toured with 28s and with 32s, didn't notice much difference. With a total of 275 pounds I did some dirt roads as part of a long tour.
I've even done short tours on 23s.
The best way to find out if a tire will fit your frame is to try it. I got a junk 28 from a bike shop to try on one of my bikes and it was too tight. One of my bike will not fit a 25.

cxwrench

Not really. The 'c' goes with '700'. A 700c rim has a diameter of 622mm. It's not 15 'c' wide, it's 15mm wide...most likely internal width. OP, if you use the proper terminology you won't have asshats like me correcting you all the time. Your rim will work w/ a pretty big tire, at least 32-35mm no problem. Many of us did this for years on CX bikes. One problem that others have mentioned is getting the tire out from between the brake pads when you remove a wheel. A bigger problem (if you have a road bike w/ caliper brakes) is having enough clearance for the tire in the first place. If you have normal road caliper brakes you're gonna be limited to 28mm tires at most.

Iride01 

Yes really! You need to read my complete reply. You don't even represent what I said correctly in the way you repeat it.

I take it that the OP got the 622 x 15C from a label or stamp on the rim. So I'll stand by my assertion that it means crochet or hooked rims.

https://en.wikipedia.org/wiki/ISO_57...h%20ISO%205775.

Now if the OP had given that from something stamped on the tire, then you and I may or may not be correct. Some very good tire manufacturers actually state the c is simply a further reference to 700C. However I really doubt that and think their document writers messed up and ask someone that didn't really know. Other tire manufacturers will state that the C after the width on the ISO stamp of their tires means that the tire should only be used on crochet or hooked type rims.

But like the years it took to convince the internet that Otto Titslinger didn't invent the bra, I'm sure this misconstrue will also take some time to sort itself out.

cxwrench

The 'c' is a size designator, nothing more. There were 700a, 700b, and 700d rims in the past. For whatever reason 700c survived as the 'normal' road rim size. It doesn't mean crochet or hooked bead. If that were case then maybe you could explain how there are 700c hookless rims now. Like Enve and Zipp are making. I'll be waiting.

LeeG

When I was 145 lbs riding with 15 lbs of gear 28 mm worked fine. It matters how much weight is on the tire as well as the road type. If you’re above 175 lbs or carrying 25+ lbs on the rear wheel I’d suggest 32 mm if the frame has room. I prefer a heavier tire on the rear with strong sidewalls if there’s a moderate to heavy load back there since riding through rocky spots can damage a light tire sidewalls that’s heaviky loaded. So 32mm is a reasonable upper limit for the rim. I’ve put 35 mm on 13mm inner widthrims and it feels weird in turns, Back in the 80’s I saw people with heavy loads on 25 mm tires and it was nuts.
If in doubt ask your local bike shop.

Iride01 

Because even the rim manufacturer's see the advantage of saying 700C just like the tire manufacturer's do. That's a marketing thing. Most people still think of their tires as 700C and have no idea about the real size of their tires or rims.

We were talking about what the ISO size meant. Not what the 700C means.

Not that any tire or tube manufacturer has to even follow ISO standards. There is nothing regulatory about it and it is quite out of date for things made today. So that's where the disparity of what you and I are discussing comes in. So you have to know which rim and tire manufacturer you are talking about to even correctly say for certain what a size designation means.

So if you need more evidence then how about this from Continental Bicycle Tire ...

https://blobs.continental-tires.com/...otice-data.pdf

If you wish you can go to Schwalbe's site and dig up the one that says C is simply a reference to the old french sizing system. But that's not in my favor. But at least I gave you something for you to back up your so far unsupported assertions where I have now given two in my favor.

cxwrench

I rarely quote Sheldon, but have a look at this chart, about halfway down the page. It's the one titled 'French sizes'.

Tire sizing

msu2001la

OP: You'd be fine running 32mm on those rims. The only caveat I'd add is that it's not going to give you the most optimal tire shape in terms of handling, so if you're planning on routinely railing corners at extreme lean angles then you'd probably want a narrower tire.

You mention "off-road" in your original post. You've likely concluded that your current 23mm tires are insufficient for anything other than smooth pavement. A 28mm road tire is more capable, but still not good for much beyond very smoothly graded dirt/gravel roads. I'd recommend going larger if your frame can handle it.

DangerousDanR

Someone else calls them 700 x 25C

Racing Dan

You need a ETRTO chart to see what tyres go with what rims. A 32mm fit on a 15mm internal rim, but may not fit in your frame or in your brakes.

63rickert

Vegas Triker @ 12 above refers to a Sheldon Brown page. Which relays current ETRTO guidance. Yes, a 15mm internal rim takes a 32mm tire. The ETRTO guidance is the range where absolutely nothing might go wrong. You can use wider tires than that on a 15mm rim.

In early days of MTB we all rode big tires on narrow rims. Back in day when I routinely rode 28-35mm tires on 13 and 14mm rims it was noticeable that the tires squirmed a bit above 30mph and sprints could get too interesting. When good wider rims became available same tires worked much better. But at normal speeds no one would notice anything.

I can imagine touring loads might provoke squirming. And will also say that back when most rode narrow for everything and a 28mm tire was considered just huge lots of people toured on 13mm rims. Those who rode wide tires did much better than those who paired the narrow rims with narrow tires.