Understanding Tire Sizes | Tech Tuesday #145

So many numbers! So many standards! WHY CAN'T WE ALL JUST GET ALONG!

Calvin and Truman take you on a tour of tire sizes and help decipher what all those numbers on your rubber mean on todays Tech Tuesday!

Questions or comments? What kind of tire are you running? Let us know below!

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For more on tire, tube and wheel fit standards check out:

[SamanthaNickole]

Started confused and ended up partially confused.🤣
I need to see and hear it all physically explained right before me. Like hands-on experience.🙃

[thatsschwinn]

I found a couple of examples on my 27" tires... E.T.R.T.0 numbers
22-630 size 27" 1/4
28-630 for same size 27" 1/4
Nice demonstration...👍🔧🚲

[dalezapple]

Absolutely a big problem with bike industry, including the 20 or so different seat post diameters

[DestroyerOfWords]

Finally found someone who was able to explain this!
THANK YOU!

[mattgriffith]

Mine are 44-559. Never knew what those referred to until this video! Thanks!

[eccchung]

thank you so much for your explanation. your videos explain clearly and clear my doubts.

[type]

I have a 1991 Bridgestone MB-0 with slicks (I bought it new, to use as a fast hybrid, before hybrids were a thing) - tyres are 25-559 (26 x 1).

[gtjpjyb]

31 x 559 sun rims single track rims with maxxis 55 x 559 26 x 2.5 " High Roller 2 on a full suspension all mountain bike or what they call Enduro now. Im Old school.
Love what you do Calvin and Truman keep up the entertaining and informative work.
By the way I only buy Park Tool tools. They may be dearer than most but so far the quality has been good (hope it stays that way) and everything is colour matched in Park Tool blue and that helps with my OCD.

[squishybiker]

32-622, 44-622, 58-622, 61-584, 76-584
As the tire pressures come down, I look for wider rim to tire ratio - I changed to in 30mm inner for the 61-584 tires to run 28psi front, and 40mm inner for the 76-584 tires to run 10psi front

[lindsaycantrell]

Great video thanks guys, I'm totally confused by my 37-406 (20X1.35) recumbent tire, A 20" tire doesn't fit because the 406 is a 16" rim outside diameter, so the actual size at base of flange would be 386mm, I wanted to use a fatter tire like a marathon plus but what size do I order, confused !!

[nigeljohnson]

Great video guys, why doesn't the bike industry come up with standards that are the same throughout, its so confusing some times.

[jeanvillasin]

Thank you this was the only video that explained this properly

[darthbiker]

Thanks for explaining the ETRTO system. Now how about the other two you referenced?

[bradklaatu]

Thanks for all that info. Now I've gotta lie down until my head stops spinning. Oh yeah my #25.622.

[tedoyle]

Great video gents, I do appreciate it.

[kevindekeerle]

I always look for the ETRTO number on a tire. That's the only number I use when I buy tires for our bikes. My mom has an E-bike with 47-622 tires

[edsemon]

622 x 20 rims, came with 38-622 1907P-2 changed up to 54-622 K1047-003 for riding on sandy trails here in SW Florida, works great

[tenpennyguy]

what fun. I work a lot on older bikes. So of course 1.75" width is not 1 3/4", and the 26" inch diameter is a different 26" for each. Some kind of translate table from you folks would be lovely. The good news is that bikes last a long time. The not-so-good news is that tech Tuesdays tend to cover today and tomorrow bikes, not so much the 'proven technology' (read 'old') examples that are most of what I see.

[marvinfernando]

Etrto 584x24. What is the best to hold my weight? I’m 100kgs.