There are a wide variety of wheel sizes available on bicycles today, and if you explore folding bikes, recumbents, and other specialty bikes you’ll discover even more. Why are there so many options? Why are there so many names for the same sizes? How do you know what’s best for your style of riding? It can seem like a daunting topic but we’re here to explain everything there is to know about bicycle wheel sizes.
Let’s Start Small
16″ Wheels (ISO 305 mm)
While they are most commonly found on children’s bicycles, 16″ wheels are generally the smallest bicycle wheels you’ll see on adult bikes. They are used on some adult folding bicycles in order to offer a compact folded size, but they sacrifice ride quality as a result. While they are perfect for the young ones just learning to stay upright, 16″ wheels don’t fare well over bumps or rough roads. The smaller the wheel, the more it will be affected by even small debris and rocks, and potholes can swallow a 16″ wheel whole.
The handling and feeling of riding a bike with 16″ wheels will be considerably different than the full-size adult bike you’re used to. The turning radius and wheel base is smaller, which can result in overly sensitive steering. Smaller wheels also require larger gear ratios to get them turning fast enough to keep up with other bikes. This makes hill climbs considerably more difficult.
20″ Wheels (ISO 406 mm)
20″ wheels are the standard for BMX bikes, and the most common size for “small wheel” folding bikes. They’re chosen by BMX riders for their maneuverability, making flatland and aerial tricks easier, but for the normal rider they still have many of the small wheel drawbacks mentioned above. While marginally better than 16″, the 20″ wheel will still be affected by rocks and obstacles more than larger standard wheel sizes. Smaller wheels also require unique frame geometry and an extra long handlebar stem in order to provide a normal upright position for the rider. This can further exacerbate the handling issues and allow for unwanted flex in the steering column and frame.
ISO 451 – It should also be mentioned that a slightly larger wheel size exists that is also normally referred to as 20″. That is the ISO 451 rim. This size is used on some racing BMX bikes and a handful of classic British shopping bikes. ISO 451 wheels are quite rare on modern bikes so most often you can assume that a 20″ wheel is ISO 406.
24″ Wheels (ISO 507 mm)
A fairly uncommon size, 24″ wheels are most often found on junior mountain bikes, and a handful of BMX “cruiser” models made for larger riders looking for the same geometry and maneuverability of their 20″ counterparts. With more emphasis than ever on youth racing, and an increase in high end specifications for kids mountain bikes, the 24″ junior mountain bike category is growing.
Standard Full-Size Wheels
26″ Wheels (ISO 559 mm)
26″ wheels have a long history in the bike industry. What started as the standard for American made cruisers almost 100 years ago, later became the most popular mountain bike wheel size and remained on top for decades. When the world’s first mountain bikes were being fabricated by pioneers like Joe Breeze, Charlie Kelly, and Gary Fisher, old 26″ cruiser wheels were the only bicycle wheels around that had wide enough tires for the demands of the off-road. As the standard for mountain bikes, this size is used on many high performance folding bikes, including Montague’s Paratrooper line.
As with most bike wheel naming conventions, the term ’26 inch’ does not refer to the diameter of the wheel itself, but rather the approximate outside diameter of the tire that fits this wheel size. The actual ISO diameter of a traditional 26″ wheel is 559 millimeters.
27.5″ / 650b Wheels (ISO 584 mm)
One thing that makes bicycle wheel sizes notoriously confusing is the use of different names for the same size. Wheels with an ISO diameter of 584 mm were originally known as 650b, and were first introduced on French touring bikes in the 1960s. Being slightly smaller than modern road bike wheels, their use persisted on small and extra-small road frames that couldn’t accommodate a 700c wheel. The size is still referred to as 650b when used on road or gravel bikes, but it has also been adopted and renamed by the mountain bike industry.
In recent years, mountain bikes have been moving toward larger wheels, and when 650b was re-purposed for off-road it became known as 27.5″. When compared to the 26″ wheels that dominated the MTB world, 27.5″ wheels have a variety of advantages, including the ability to roll over obstacles more easily, a larger contact patch for more traction, and more rotational inertia to maintain momentum. The Montague Paratrooper Highline and Paratrooper Elite both use 27.5″ wheels, and are the first folding bikes in the world to do so.
29″ / 700c (ISO 622 mm)
Here we have two more common wheel sizes that are in fact, exactly the same! The standard modern road bike wheel has an ISO diameter of 622 mm and is referred to as 700c (makes sense, right? /s). The history of that name would need a whole other blog post to fully explain, but the short version is that it came from international tire sizes where the outside diameter would be approximately 700mm, and multiple rim sizes would be labeled 700a, 700b, 700c, etc. The others died out but the 622 mm rim became the most common for narrow road tires, and almost every adult bike in the world made for use on pavement comes equipped with 700c wheels, including Montague’s line of Pavement folding bikes. Using this full-size wheel offers superior performance and ride quality to small wheel folders.
Just as the 650b wheel was adopted by mountain bikers and became 27.5″, the 700c wheel has taken the mountain bike world by storm in recent years and become known as 29″. All the advantages of a larger wheel mentioned above are pushed to the limit on a 29″ (or 29er) mountain bike, although some riders feel the sacrifice in maneuverability and turn radius are not worth it. While the diameter for both 29″ and 700c wheels is the same at 622mm, rims made for mountain bikes are generally wider to accommodate wider tires.
27″ (ISO 630mm)
The ISO 630mm size is essentially no longer in use, but is worth including due to the huge number of American road bikes from the 1970s and 80s that used these “27 inch” wheels, and are still hanging around in basements and garages all across the country. The rim itself is slightly larger than modern 700c wheels, which has been learned the hard way by many of us after buying a new road tire and struggling to get it seated. Tire makers still produce 27″ tires due to the sheer number of these wheels in circulation, so if you need a new tire for that vintage steel racer, ask your local bike shop to order one.
Oversized
32″ (ISO 686 mm) and 36″ (ISO 787 mm)
While extremely uncommon, custom built frames for very tall riders often use 32″ or 36″ wheels. These sizes are almost never found on production bikes, but if you’re over 6′ 6″ and looking for a bike that fits, custom built might be the only way to go. Do a quick search for “Shaq Bicycle”, and you’ll see the various bikes that NBA legend Shaquille O’Neal has had built over the years. While the wheels may look proportional to the frame, they are all monster 32″ and 36″ sizes.
What are the standard widths on bicycle rims?
And Adel combinations and how much to allow for gear stack?
Is there a publically available (free) published standard?
Thanks in advance.
There is not a single standard for bicycle rim width, and they do vary. Rims intended for a wider tire, like mountain bike specific rims, will be wider than those intended for narrower road tires. They can range anywhere from an internal rim width of 13mm up to around 29mm.
another important factor is what tire width will the highline frame allow?
The Highline, and all of our current mountain models, can accommodate up to a 2.4″ tire.
what about 28″ tires? what are the rim size or tire size numbers on the tire? are 27.5 rims 28″ tires? are 700 tires a 28″ rim and 27″, 27.5″rim?
I have Alexrims HRD 622-17 29 They were originally booted with 700x45c tyres. Looking at 700x47c tyres. Will they fit or better to keep to smaller width.
Some tires have the main wall casingfilling out the full nominal width, some have a slightly smalker casing but very prominent rread knobs that stick out to thr sides, so you can’t always go by the stated size.
The width of the rim affects the width the tire expands to, also, changing the nominal width slightly.
You’d just have to try it and see. In a shop rather than mail-order!
Is there a bike rim that is 19″ in diameter, 1″ wide? Where can I find one like that?
The wheel size commonly referred to as 24″ has an ISO diameter of 507mm or about 19.9″. That’s probably the closest common size.
I am having a hard time finding road or hybrid tires similar to the ones currently on my bike in 26 x 1.5″ size. I think the bike was nominally billed as a mountain bike or maybe a hybrid when originally sold back in 1990 (it’s a Trek 850 Antelope), but I don’t ride on anything but pavement (I use it for commuting to work). What I’m finding while shopping is it seems wheels meant for road tires are usually larger diameter, and mountain tires are available in 26″ but are all much wider (2″+) and (obviously) in tread patterns intended for off-road. The closest I’ve been able to come is 26 x 1 3/8″. Can I use a tire of a slightly different width like that, or would it not seat properly? I’m not keen on the idea of replacing the wheels with a more convenient size, if they would even fit, because that looks like being very expensive – surely far more than the bike itself is worth at this point.
26 x 1 3/8ths is another obsolete wheel size, common on English makes like Raleigh, the vintage bikes with an upright ride often fitted with Sturmey-Archer 3-speed hub gears and baskets, again there are many kept as family heirlooms and tires can be special-ordered. But not the same as 26-inch mountain bike tires, those will not fit.
Various companies make the tires this guy wants, narrow road-specific tires for 26-inch mountain bike wheels, usually 1.5 to 1.75, also 1.9-inch. These run higher pressure, and have a smooth surface, or small or ‘negative’ tread patter, or a hard central line and knobby treads down sides to be dual lurpose road or track.
Specialised even made extra narrow very high pressure 1.25 tires to fit mtb 26-inch whhels, i haven’t seen these since the mid-1990s in the USA, but you could enqire with a Specialised dealership.
Another obsolete wheel size is the English vintage 28-inch (sorry, i don’t know rim diameter in mm) , common from thr 1890s to the 1970s, exported around the world, and still made lafer (till quite recently) in countries like India also China.
If you have a big black old upright English bike with rod-pull brakes, this is the size you would need to special-order
Except with disc-brake wheels, swapping wheel sizes will leave you not only with changed geometry and handling, but with problems aligning cantilever, V type or caliper brakes.
My folding bike uses so-called 18″ wheels (355), so there are definitely more sizes out there.
I have a Giant road bikecwith 700×23 tires. Someone just gave me 700× 38 tires. Will they fit? By eyeballing, seems the forks cannot handle the size.
It’s hard to say without knowing the geometry and clearance for that specific frame and fork. Road bikes normally have pretty tight clearance, so a 38mm tire might be too wide. The other thing to consider is if that rim is wide enough to accommodate the tire. You would want the rim to have an internal width of at least 17-18mm for a 38mm tire.
I have an old 1983-4 Bianchi road bike that has 700x32c tires (not the originals, but pretty old). Can I go with narrower tires on the same rims? The rims don’t have any markings designating their size.
That depends on the width of the rim. If you remove the tire and measure the internal rim width, you can determine the minimum and maximum tire sizes it can support. If you want to go down to a 25mm tire for example, your rim would need to be no wider than 18 or 19mm on the inside. With a 28mm tire, you could get away with a 20mm or 21mm internal rim width.
What would be the width range for a 700x28c tire?
There would really be no minimum rim width for a 28mm tire since that’s a fairly narrow tire in the greater scheme of things. You just need to worry about the rim potentially being too wide and a 20 or 21mm internal width would likely be the maximum.
Hi- this is probably the most basic question ever- and I feel dopey asking but because I’m not bike savvy the tech talk has my head spinning. I haven’t been able to find a simple enough answer Lol.
If a bike has 700c tires does that make the bike/frame taller/bigger?
Last year I bought a used bike made in the Netherlands. I thought It was 26”- that was what the ad said and I didn’t really go over the bike or even ride it because I was desperate, I don’t have a car and and the guy delivered. Well, the bike is a beast- tires are 28” and the frame is steel and heavy as hell. It’s too much bike for me. I feel very precarious on it and have had to walk it several times. I don’t even ride it now it’s been parked in my buildings parking garage ever since. I need a bike as basic transportation for visiting friends, taking dog to the park, around town errands, grocery shopping with the dog trailer. I should mention I’m 71, female and about 5’6” and haven’t done any real biking in a long time. I don’t want anything taller than what a 26” bike is- if I could get away with 24” I would.
A few bikes I’ve researched had the reasonable price, the low Step through and the aluminum frame that I need but tires listed as 700c.
Sorry for the length of this question. I’m just really confused!
Wheel size and frame size are generally not correlated. Most adult road bikes use 700c wheels, whereas 26″ is typically a mountain bike wheel size (although in recent years mountain bikes are using larger wheels as well). Sometimes very small adult road bike frames will use a smaller wheel size (like 650b), but it’s more common even for small frames to use 700c wheels. At 5′ 6″ you’re not quite in that very small frame category, and it’s completely reasonable for a frame suited to your height to use 700c.
Do you know what size a Sears and Roebuck and Company old school bike tire is?a26 is to small& a27 is to big. I have the rims it doesn’t have the size on it.how do I get the tire and tube size. Thank you
I have a 2019 townie 7d with 26″ x 2 tires. I bent the front rim and found a 26 x 1.5 wheel for sale. is the second number the width and if so how does that compare to the townie oem wheel? The oem is very skinny, almost road bike in width.
You mention your current tire width is 2″, but refer to the potential replacement as 1.5″ wide wheel. 1.5″ would be very wide for the rim itself (which is normally referred to in mm), so I’m guessing that’s the size of the tire that is on the new rim? Or the recommended tire size from the seller? If it’s recommended for a 1.5″ tire, then you’ll likely be fine with a 2″ tire unless it’s a very narrow rim.
The internal width of the rim is what you really want to know, which would be in mm, likely somewhere between 15mm and 25mm. To mount a 2″ tire, you would want the rim to have an internal width of at least 17mm. The only real issue would be if the new replacement rim was too narrow, it might be difficult to mount the tire and you could risk it rolling off the rim.
They only state it as a 26 x 1.5 32h and it doesn’t come with a tire, so what was confusing me. I’m going to have to email them and also measure the internal width of my current rim. Id like to go wider than the current as they look very pinched in on the stock rim
Little off comment here but could you tell me how to judge frame size on a Montague? I’m looking at buying a used one but there is no mention of a frame size on the bike. What can I measure to denote the difference?
Thank You!
Frame size corresponds with the actual length of the seat tube, measured from the center of the bottom bracket spindle, to the seat post quick release. On our pavement models this would be either 17″, 19″, or 21″ and on the mountain models, 16″, 18″, or 20″.
I have been looking up about tyre sizing to rim sizing after a gap of 20 years from riding a racing bike. My last bike was a Dawes Stratos (’89). Where ISO standards seem to have made things simple, it has confused me even more in the sense that my first bike when I was 10, (borrowed from mothers boyfriend) was an old French Viscount 1968 bike.
I came off of it in a roadside dike one day (’84) & when I bought new wheels for it, they didn’t fit, but the reason they didn’t fit was because these wheels (700c – 26~”) where to small leaving the brakes to grip the tyres. I measured across the old rims without tyres & they measured an actual exact 28”, & yet the list of French sizes of ISO doesn’t go that high in inches? What gives?
Why don’t you mention of and elaborate more on size 28″ wheel as commonly used in Dutch citybike?
I am bring my 1992 Dyno VFR back to life… My question is this, I measured the wheels and the wheel itself is 16″… The tire that is on it is marked 20×2.0. I know the standard and wheel size is 20″, but why are the rims measuring 16″?? Am I missing something? I want to order new wheels for it, but I want to order the right size… How come the wheels themselves measure 16″ but are rated as a 20″? ?
The common names for wheel sizes are usually an approximation of the outside diameter with a tire mounted to the rim. The actual diameter of the rim is usually considerably smaller. For example, the ubiquitous 26″ wheel has an ISO rim diameter of 559mm, or about 22″, but if you put a 2″ tire on it then the outside dimension is about 26″. The same goes for 20″ wheels, which have an ISO diameter of 406mm (or about 15.9″).
Could you tell me, what is the inner rim width on your 38 mm tire for the Allston?
Thank you
Hi Nathan. The inner width on the Allston rim is 20.6mm.
is there any 44mm head tube frame?
All of our current bikes, with the exception of the Crosstown and Paratrooper Express, use a ZS44 headset. Those two models use a EC34 headset.
Do all different sized 559 tyres fit
all 559 (26″) wheels. I have acquired a pair of 2nd hand 26″ rims which I am told take 1.95 to 2.1 but I would like to fit them with a 1.50 tyre.
Tire width is another consideration. The range of tire widths that can fit on a rim are dependent on the internal width of that rim. It’s not possible to put a very narrow tire on a very wide mountain bike rim for example, even if it is the correct diameter. However, the acceptable range is typically much larger than just 1.95″ – 2.1″. As long as the internal width of that rim isn’t wider than say, 24mm, you should be able to put a 1.5″ tire on there.
Hi, I have a haibike trekking 5.0 with 700x38c road tyres fitted, I would like to fit something a bit wider and grippy for occasional off road/track use. What tyres will fit my rims ? Thanks
My tire size is 16 but a 16 inner tube didnt fit the rim. What could be the problem
Hi there,I’m looking to buy my first bike and I’m looking to get one juts to cycling in the city on the weekends. Can you advise bike sizes and what she’ll I look out for? I’m 191cm tall so looking to have a big bike ish. Thanks for your help in advance
Alex
If you’re considering a Montague bike, I would certainly recommend our large frame size at your height. That would be the 20″ frame for mountain models, and the 21″ frame for pavement models.
Im 75, 5’2”, need the easiest tricycle to use for grocery runs. 24” vs 26”? Know nada about bikes. Any wheel types help with ease of pedaling? Car not in budget. Thank you.
While a larger wheel can provide a more comfortable ride and roll over bumps and obstacles more easily, ease of pedaling is really a product of the gear ratio. You could certainly have the same “ease of pedaling” on both a 24″ and 26″ wheel, so I would personally recommend going with a 26″ for better ride quality.
I have been struggling with an issue for over 6 months until I came across this forum … I’d like to think it a life saviour for me.
The tires on my foldie are Schwalbe Durano and the markings read 28-451 (20 x 1 1/8). The tires are very sleek and it does not suit my riding style as I am not speed riding.
The rims are from Hubsmith (ref high profile rims??) and the width (external) measure 22mm.
I know nothing about the all-confusing references and jargons used in describing and matching rim size to tire size.
The front fork and rear can fit a max of 1.5” tire width.
I’d like a wider set of tires (not sleeks) and info from internet is driving me nuts. I searched for 20” tires and the specs indicate ‘406 (20 x 1 3/8) fit my 22mm rim width?
The use of Imperial measurements in combination with Metric is driving me crazy. It seems the rim/bicycle manufacturers and the tire manufacturers are taking in different languages.
I need help in layman’s terms … please at least indicate the brand and full specs of the tire you recommend and I can buy it off the internet. Appreciate whatever you advise. Thanks.
I have a 1991 Giant 890i AFT (cross bike). The tires say 26 x 1.38. I can’t find 1.38 tires anywhere. I found an old catalog and it said my tires are 38mm. With them fully inflated (85psi as it says on the tire), if i just hold a ruler up to them, the are no where near 38mm wide. They are more like 30 -33mm. There are no other size markings on the tires. No ISO or ETRTO. Can you help me understand what size tires these are or what size I need to buy, in current tire terms? Thank you.
Hi Susan. 26 x 1 3/8″ is a fairly common tire size. As a decimal, that’s 1.375, so it’s possible that particular tire maker decided to label it as a decimal and round it. You should be able to find 26 x 1 3/8″ tires fairly easily. Regardless, bicycle rims can accommodate a range of tire widths so you don’t need to get the exact same size as the original. As long as the new tire is 26″ in diameter, you should be able to choose anything relatively close to the original in width.
I need to get a new rear rim for my Giant road bike but I don’t know how to make sure it will match my bike. My current rims are ETRTO: 622×14. I looked for them on the web and it says that they are regular 700C, but the with can vary. Do I need to get a 700C rim with a 14 mm with?
Thanks
I have a Paratrooper Pro 2015 that I retrofitted to e-bike with a torque sensor motor.
Will/can the frame hold 27.5″ wheels?
Thanks a lot for your guidance.
Hi Alberto. You could fit 27.5″ wheels but on a pre-2016 frame you’ll be limited to about a 2.1″ tire. We changed our mountain frames in 2016 to allow for more tire clearance so newer bikes can fit about a 2.4″.
Really? I took a look at a mate’s current Paratrooper Pro running a pair of Kenda slant six 2.1 now. It appears to me that even running a 26×2.3 on it would be a challenge given the chainstay constraint, especially when knobby tyres often have width beyond their stated size. 27.5×2.4 possible you say? We wouldn’t want to risk buying a wheelset and tyres to find that they won’t fit. Which model of 27.5×2.4 tyres were tested to fit with the frame?
What year is that bike? Older models would certainly have tighter clearance, but Paratroopers from the last few years should be able to accommodate a 2.4 (based on our frame drawings).
It is a current Paratrooper Pro post 2016 which comes with the easyrack. I do foresee that we can squeeze in a 27.5 x 2.1 but we are really unsure about it accepting a 2.4.
I come back to my question of last year. What about 29″x 2.1 on a Paratrooper with Pre-2016 frame?
Thanks
I currently have a standard roadbime with a tires of 700x25c. I’m thinking of buying a 700x32c. Will that fit in my road bike rim? Is there going to be any concerns if I upgrade it to a 32c tires?
I have a 2006 20.0 DX Grand Canyon Crossover Montague bike and would like to know if there is a quick-release rear wheel that can replace the standard 6 speed wheel that came on the bike.
Hi Jim. You should be able to source a 26″ quick release mountain bike wheel that accepts a threaded freewheel (which would allow 6 speed). Any one with those specs should work. You should also just confirm that it has a 135mm hub width, but that is fairly standard. Your local bike shop should have no problem supplying a wheel like this as well!
Thank you for this informative article!
I feel like a time traveler from the early 1970’s since that’s when I understood available bike parts. I am trying to set up a bike from that era that had sewups, and has been used with 27″ beater wheels for some decades. I’d like to put 700C rims on my nicer wheels, which should give me the clearance to put nicer brakes on as well.
I knew 700C rims are smaller than 27″ ones, but was confused because 700mm is about 27.5″. Your discussion is very helpful, but I just hope I can find the right rims and spokes and still remember how to lace a wheel.
Should add there are 2 sizes of 20 inch, in the article you said 406, but in the comments you mentioned 451. It is a souce of confusion because sometimes you say 20 inch and wanted 451 but got the 406 instea and vice versa.
Thanks for the note! We’ve added a note on ISO 451 to the post and updated the comment to mention ISO 406, as the overwhelming majority of what we refer to as 20″ these days is 406.
On a similar note 16″ can also be 349mm rim, actually quite a common size.
ISO 622 is not 29 inches. (sadly Google have this as a top search result).
ISO 630 is 27 inches and 8 mm larger than ISO622
Which imperial wheel and tire sizes still available in the USA?
Hi John. The wheel size referred to as 29″ or as a ’29er’ on modern mountain bikes is in fact an ISO 622 wheel. The name is due to the outside diameter of a mountain bike tire mounted on that rim being approximately 29 inches. This is the same reason an ISO 559mm rim is called 26″, even though 559mm is nowhere close to 26 inches.
The wheel size referred to as 27″, which was mostly phased out in the mid-1980s, is indeed ISO 630 as outlined in this article. All this confusion comes from the lack of a consistent naming convention for bicycle wheels, which is why we made this post to hopefully clear some things up! There really are no “imperial” or “metric” wheel sizes, just different names.
What is difference between wheel size and frame size…? And which one is deciding factor for riders height and weight?
Frame size should be a factor of the rider’s height and proportions, while wheel size should be more a consideration of the type of bike and riding style. A larger frame allows the bike to fit a taller person with longer legs and longer arms, while a smaller frame puts the saddle, pedals, and handlebars closer to each other in order to accommodate a smaller person.
That said, considerably smaller frames often require a smaller wheel size in order to maintain their geometry. This is why kids bikes typically use smaller wheels, and some small adult road bikes will use 650b wheels instead of 700c.
Hi,
I have a bicycle rim measuring 21 x 1 3/8 inches outside dimensions.
What tire sizes might fit this?
Thank You!
Hi,
I have 27.5 MTB cycle and planning to convert to Hybrid please suggest the suitable tyres and tubes.
reference cycle model: Hero Octane Burracuda 27.5
I bought a paratrooper express mainly for its folding capacity but I mainly ride on roads and find it a much harder ride than my non folding hybrid so have only used a handful of times in 3 years. Would I be able to put hybrid tyres on this bike and if so please could you advice what tyre i should buy and wheels too if I need them as well (i am not bike technical savvy so as basic and instructive as possible please)
You can absolutely put a more road specific tire on the Paratrooper Express, which should help with rolling resistance and make it more efficient on pavement. The stock tire is 26″ in diameter and 1.95″ in width, but you could put any 26″ tire with a width between about 1.5″ and 2.4″ on that bike. I’d recommend going a bit narrower which would also improve efficiency on road.
I have a Kona Dew bicycle. The present tyres are (from the markings on the tyre) Continental Country Ride; 37-622; (28×1 3/4 X 1 5/8); c196. What size replacement tyres and inner tube do I need?
I’m on a Montegyu Navigator.
By default, the tires fitted are 700c x 35mm.
I’d like to change the tire, but I’d like to know the minimum tire width that can be applied.
It depends on the model year of your Navigator, but if it’s relatively recent, you should be able to fit about a 40mm tire on that frame.
Hi,
When you say a rim has a diameter of iso622, is that the total diameter of the rim or is it the diameter of the bead seat?
Thanks for your wheel size article by the way. It has been very helpful.
The ISO diameter is technically the “bead seat diameter” and is sometimes referred to as the BSD. Glad the article was helpful!
Excellent article which sadly leaves me more confused than ever… 🙂 Why aren’t wheels simply sized via the diameter of their external rims?
It would save huge amounts of confusion…
I am having difficulty determining the correct size tires for a 1928 Hawthorne Flyer. It was my dad’s bike and I am trying to make it operable again. The tires were so badly deteriorated that the sidewall was unreadable. I can’t find any specs for this bike at all. Thanks for any help!
After ignoring my advice to order and wait for a better bike, an impatient buddy of mine went and ordered a Royce Union RMT from Amazon, now he’s not happy with the tires on it (and a whole bunch of other crap, but that’s another can of worms I won’t get into)
The tires on it are what I consider “Fat tires” 27.5 x 2.0, and from what I’ve read 650B marked on the tire depicts a rim size.
With that said, I’m trying to find a narrower tire for the rims which measure a diameter of 23.5″ x 1″ inside width, and all this tire sizing to rims has me spinning with figures and calculations that I’m just not getting.
These rims are pretty much the same width as the Bontragers on my Trek Hybrid, just smaller in diameter.
Can you help me in determining a narrower tire number for these rims?
I’m tired of hearing him bitch when out riding!!!
Thanks for ANY help!!
27.5″ and 650b are names for the same wheel diameter. You have a fairly wide range of widths that are compatible with any rim, so you’ll want to look for a tire marked 27.5″ x (insert width here). If the inner width of the rim is 1″, then you could go as narrow as about 1.5″ on the tire width.
Im currently running 700 38 for my MTB that came with a rather skinny rubber causing me to loose control on sandy trails ( off road). Question is… can/what tires can i use to replace the 700 38, i mainly do single tracks. This was my sons bike i git him but hes not much of a outdoor kid so i ended up alternating it with my trail bike. Thanks in advance
ref: “Smaller wheels also require larger gear ratios to get them turning fast enough to keep up with other bikes. This makes hill climbs considerably more difficult.”
Remember that it isn’t the gear ratio that determines the ‘gear inches’ you are riding, but that ratio times the wheel diameter. A small wheeled bike (e.g. 16″) gear ratio should be set so the gear inches is in the desired range. My 16″ Raleigh RSW-16 3-speed is geared so the gear inches are the same as a ‘regular’ 3-speed 26″ bike. In my youth, a friend and I rode them on a hilly double century (miles) day.
Hello Montague,
I have Paratrooper from 2019 , so latest frame. I would like to change fork to:
https://www.sram.com/en/rockshox/models/fs-reba-rl-a9 – RockShox Reba RL (same as in Elite model) and Wheelset to:
https://eu.huntbikewheels.com/products/hunt-trailwide-mtb-wheelset?variant=31723704221751#techspecs
with tires:
https://eu.huntbikewheels.com/products/schwalbe-nobby-nic-2-35-snake-skin-front-schwalbe-nobby-nic-2-25-snake-skin-rear-tubeless-tyre-combo?variant=30587737800759
From my understanding should be good but I am totally “green” in this area.
I am worried about tire width here.
Please advice and great bike for improvements 🙂
Will this fit ?
Best regards,
Michal
Hi Michal. The particular fork you linked to has a tapered steerer tube (1 1/8″ at the top, 1 1/2″ at the bottom), but our frames are made for straight 1 1/8″ steerer tubes. My first recommendation is to find a fork with a straight steerer, but you might be able to replace the headset on the bike in order to use the tapered one. Cane Creek makes a headset for 44mm head tubes that is internal on top and external cup on the bottom to accommodate a tapered steerer without a tapered head tube: https://www.jensonusa.com/Cane-Creek-40-ZS44EC44-Headset-Tapered
The wheelset you linked to appears to be thru-axle, which is not compatible with the rear dropouts on the frame. If the new fork you get is made for thru-axle that would be fine on the front, but the rear dropouts require standard quick release (or bolt on) wheels with a 135mm hub width (that might be specified as Over Locknut Dimension or “O.L.D.”).
Regarding tire size, a 2.4″ is the absolute maximum you could fit in the rear frame of the Paratrooper.
Thank you for much for the reply.
I thought that this fork is same as on elite paratrooper. Will figure this out in bike shop and will google.
I will ask about rear hub – they have many options my main “issue” regarding wheelset is the width of the rim which is 30mm which might increase the volume of the tire.
Thank you for clarification I will search more.
Last thing. I think that will be great if you will prepare some blog post with some tests of different rims & tires sizes which you checked with paratrooper. It is common question here and looks like 26” is dead and people will be upgrading. Just my 2 cents
My tire size is 50-622 (28×2.00).
50-622 has two sizes listed: 28×2.00 and 29×2.00.
Since both are 50-622 the rim is a 700c.
I need to replace the tubes.
What size tube do I use?
28”, 29” or 700c?
The naming conventions of 28″ / 29″ / 700c are not really important here since they all refer to the same ISO diameter (622). The important thing is getting a tube for the correct iso diameter (622) that covers a range of widths that includes your tire width. Some tubes like this might be labeled 28″, and some might be labeled 700c, but they should all have the 622 specified there along with a range of widths.
How wide of a tire can you put on the 27.5” models you sell?
The current Paratrooper Highline and Elite should be able to accommodate up to a 2.4″ tire.
Hooray! At last an article that actually seems to give accurate information upon how to size/measure a bicycle wheel!
I’ve just spent days trying to figure this out by reading numerous internet articles most of which offer simplictic and banal information on measuring not WHEEL but TYRE size and don’t even get that right!
Many of these articles in fact seem to look as if they were written using information gleaned from other innacurate/plain wrong articles. (A lesson to be bourn in mind by internet researchers).
Thanks to the person/persons who wrote this article for NOT being phoney idiots who do not know what they are talking about!
great article. Knowing bike wheel sizes is necessary for putting the tire back on the rim because some bike tires won’t go on the rim because they’re not the right size.
Hi there! I’m still confused.. talking about circunference lenght, a 26″x 2.5 slick tire is bigger or smaller than a same size off-road big treaderd One?
Thanks and Happy holidays
If both tires are labeled 26″ x 2.5″, the outside diameter of both is going to be extremely similar. However, the actual width of a tire does not always match the labeled width (the 2.5″ in this example). The exact width can sometimes vary a bit between different brands or different models of tires even when they’re both labeled 2.5″. So, it’s possible that the knobs on the knobby tire might stick out a bit more and make the effective width or outside diameter slightly larger on the knobby one.
I am approaching 80 and having a difficult time dismounting my 45 year old Trek road bike, probably because I am shrinking to 5’6″ from 5’10″” as I age. I love the bike and wondered if I can just replace the wheels with an appropriate size that you might suggest.
The bike frame would have been designed for a specific wheel size and switching to smaller wheels can present problems. Smaller wheels would lower the bike to the ground making it easier to mount/dismount, BUT it would also lower the crank and pedals toward the ground significantly. You would likely experience pedal strike (the pedal hitting the ground at the bottom of the rotation) especially when cornering. In addition, if the bike uses rim brakes, those brakes would likely no longer reach the rim since the smaller diameter wheel would be farther away from the brake mounts. Your best bet is likely to get a new bike with a smaller frame or a step-through frame design.
The 451mm wheel size is so rare that it’s on every BMx bike sized expert and smaller at the race track. Then the Pro sized bikes are also using it labeled as OS20
what size tire would you need for a 23″ rim ?
it’s off a atb bike it’s a mtb bike with no shocks and it’s a early 90’s or late 80’s
bike
As a student project, our team have decided to do a project on dutch trike with two 24-inch wheels on the front and a 26-inch wheel in the rear…. Is this a good idea??
I need a step through bike because of a knee replacement. I am in my late 60s. I want an electric bike. I am very tempted by a very low step through bike that has approximately 20 inch diameter wheels with about a 1.95 inch tire width. I am reconsidering because I’m afraid that if I go off of a shoulder that is one and one half inch high or higher, I will be more likely to wreck than with a normal diameter tire of say 28 inches. I have been shopping for electric bikes for a week and I am a hard fit. Some of the nice medium sized bikes with shocks in the seats are a tad too high for me and the small bikes are a tad to short in length for me. What can you tell me about the small diameter wheels? I made a poor purchase of a great bike that did not have a good center of gravity. It was pushing me over because of that and the 65 pound weight. Now, I’m shopping for ones that have the batteries in the center post. Right now, I’m worried about tire diameter. Thank You.
( I used to be a very well coordinated person. The surgery changes ones balance a bit. On a recent ride a slow moving man on a bike caused me to ride to the edge of the road and ride into the gravel slowly. I did that to avoid him. Then there are children on the Cades Cove Loop who do unexpected things. I still have fast reflexes but I’m older and I have to be very careful. I move more slowly on purpose. I don’t have the strength that I once had and electric bikes are a different animal)
Great breakdown of the different bicycle wheel sizes! 🚴♂️ It’s amazing to see how each wheel size impacts the ride experience – from the compact 16″ wheels used on folding bikes to the larger 29″ wheels that are dominating the mountain biking world. I had no idea that 27.5″ and 650b were essentially the same size but used in different contexts for road and mountain bikes. It’s also interesting to hear about the history of wheel sizes, like the now-obsolete 27″ wheels that were popular in the 70s and 80s.
For anyone just getting into cycling or looking to upgrade their ride, understanding how wheel size affects performance, handling, and comfort is key. And if you’re considering getting a new bike, BikesOnline AU – https://www.bikesonline.com has some great options to match your riding style. Thanks for the informative post!