Help: rare'ish Tire size, and possible miss-labelled tire at Shop

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Merida CX90_D-4
Posts: 11
Joined: 28 Jul 2022, 4:20pm

Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Merida CX90_D-4 »

hi ! all

any1 here, kind enough to help regarding making sense on Tire data lable ?

i live in a Country side at rural area, and i found a New tire (obvious NOS stock) at neighbour town...

i have a Vintage 80s RoadBicycle "Tour de France" style, or waht is the correct english term...

Anyway, it has Rare'ish Tire size "26 like in some French Post Office bike....that aint Standard "26 ...... its like 0,5-1cm smaller than common MTB "26 from 90s until this day.

The Spec lable at the NOS tire at Shop is very confusing to me... (a big market-crocery shop where doesnt exist customer help...)

my bicyles OEM tire is:
Impac Voyageur (which is very old and Perishing...)
44-584
(650 x 42B-26 x1 5/8 x 1 1/2 )

the NOS tire at shop is:
DeliTire ,whitewall
paper lable says:
26x1 1/2 ( 37/40-584 )
Tire wall has casting-mold markings: 35-584 ( 650x35B-26x1 1/2 )


My guestion is that, is the DeliTire above, correct fit onto my Bicycle......?

i hobby and restore my Native made Vintage bicycles in this Genre... Help muchos appriciated....
ive seen only once exact same Impac Voyageur 44-584 on another Native made Bicycle from mid 90s or early 2000.

bye:)
m
Jdsk
Posts: 24488
Joined: 5 Mar 2019, 5:42pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Jdsk »

It isn't you! There are multiple sizing systems and they are inconsistent and confusing.

I recommend

1 Starting with;
https://sheldonbrown.com/tire-sizing.html
which explains the systems and has ISO equivalents.

2 Using ISO sizing to check what will fit what.

Jonathan
Jdsk
Posts: 24488
Joined: 5 Mar 2019, 5:42pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Jdsk »

In ISO sizes:

Your current tyre is 44-584.

The tyre at the shop is 35-584.

Jonathan
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Paulkentuk
Posts: 65
Joined: 9 Sep 2022, 12:41pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Paulkentuk »

Hi,

If you enter the dimensions of your original tyre in the old Imperial inches format it has on it , ( 26" x 1" 1/2 x 1" 5/8) into a search engine, you can purchase a correct tyre size here for example :-

https://www.cycleking.co.uk/tyre-and-tu ... R8EALw_wcB
Merida CX90_D-4
Posts: 11
Joined: 28 Jul 2022, 4:20pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Merida CX90_D-4 »

hi !

the thing is that in my Country (northern Scandinavia Arctic Cirle) where i live, there is no Sales Stock for 44-584.

i would have to special order it Abroad most likely, too pricy.

Where as if the Mentioned DeliTire is correct rim fit, its fully ok to me. No matter if its Narroer-Slimmer or Lower side profile, as long as it has Correct Fit onto the rim.

The mentioned DeliTire has basically 3 different Size-range fittment mentioned on it.

The Impac Voyageur 44-584 is FAT like common MTB Tire 26x1,95 ,where as the Mentioned DeliTire is very SLIM racebike like...
i wonder if it fits onto my RIM, id like-prefer skinnyer racetire anyway...
the snail
Posts: 333
Joined: 5 Aug 2011, 3:11pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by the snail »

My guess is that it will fit ok, but to be sure you would need to know the internal width of the wheel rim, which might be marked on the rim.
tatanab
Posts: 5030
Joined: 8 Feb 2007, 12:37pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by tatanab »

Both those tyres are 650B size with a bead seat diameter of 584. Far from being rare, 650B is the modern fashionable size for MTB and gravel bikes, so it is a fairly common size in those markets.

Your potential replacement tyre is not much narrower than the old one, and is still a pretty fat tyre, so I would expect no problems with fitting it to the rim. It does not sound as if you have much choice any way.
fastpedaller
Posts: 3433
Joined: 10 Jul 2014, 1:12pm
Location: Norfolk

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by fastpedaller »

the snail wrote: 16 Jan 2023, 4:48pm My guess is that it will fit ok, but to be sure you would need to know the internal width of the wheel rim, which might be marked on the rim.
Or measure it!
Merida CX90_D-4
Posts: 11
Joined: 28 Jul 2022, 4:20pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Merida CX90_D-4 »

hi !

Impac Voyageur 44-584.
DeliTyre at the shop is 35-584.

what is the difference then between 44 and 35 ? or 35 Versus 37 and 40 (37/40)


42B and 35B , does it Indicate side profile height or how Slim-Wide is the Tire ?



I dont know much about Current Era Gravel/MTB Tires on Category outside normal "26 from 90s ( 26x1,75 26x1,95 26x 2,05 )

but i can say that 26x1,95 MTB tire was way too big center Diameter for my Rim 44-584.
MTB 26x1,95 tire had like 0,5-1cm too big center diameter.

i have many 90s MTB rims....
tatanab
Posts: 5030
Joined: 8 Feb 2007, 12:37pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by tatanab »

The measurement is the nominal height and width of the fitted tyre. Nominal because it also depends on rim width.
Merida CX90_D-4
Posts: 11
Joined: 28 Jul 2022, 4:20pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Merida CX90_D-4 »

ok, so basically 42B versus 35B was as i thought it would be, and not a Reason why DeliTire would not be suitable...

-"42B and 35B , does it Indicate side profile height or how Slim-Wide is the Tire ?

quote, reply :
-"The measurement is the nominal height and width of the fitted tyre. Nominal because it also depends on rim width."

Sorry for me repeating, as im not UK native, not my native language, as i clarify above...

What then is difference on below as "35B" version doesnt have "1 5/8" ?

(650 x 42B-26 x1 5/8 x 1 1/2 )
( 650x35B-26x1 1/2 )
Carlton green
Posts: 3630
Joined: 22 Jun 2019, 12:27pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Carlton green »

As I understand it:

650 x 42B inflates to about 42mm wide, fits on a standard 650 tyre rim and has a B inflation profile.
650 x 35B inflates to about 35mm wide, fits on a standard 650 tyre rim and has a B inflation profile.
The 1 & 5/8” (roughly 42 mm) dimension can be ignored.

The new tyre would be 7mm narrower than the old one, but 35mm wide might well be enough for most practical purposes - I run on 700 x 35C tyres and they take me along any tarmac road, gravel road and hard packed soil path that I want to go along.

Look here and about halfway down the table you should see details of the 650B tyres :
https://www.cyclinguk.org/cyclists-libr ... tyre-sizes
The inflation height and the tyre’s outside diameter will be slightly smaller for the 35B tyre than for the 42B tyre.
See also the 27.5” tyres on this chart: https://www.michelin.co.uk/bicycle/tips ... onversions
It’s perhaps not a common size (650B) but there are plenty available, not cheap though: https://www.sjscycles.co.uk/tyres-26-27 ... +ascending

In your position I’d buy the 650 x 35B tyre because:

It’s almost certain to both fit and work well enough.
It’s not too expensive.
Your old tyre isn’t fit for more use.
Nothing else is easily and cheaply available to you.

Good luck, though I don’t think that you’ll need it.
Last edited by Carlton green on 17 Jan 2023, 9:56pm, edited 3 times in total.
Don’t fret, it’s OK to: ride a simple old bike; ride slowly, walk, rest and admire the view; ride off-road; ride in your raincoat; ride by yourself; ride in the dark; and ride one hundred yards or one hundred miles. Your bike and your choices to suit you.
PT1029
Posts: 1742
Joined: 16 Apr 2012, 9:20pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by PT1029 »

If 650B tyres doesn't work for you, it is possible to convert to 26 X 1 3/8" tyres/rims which are close in size but not quite the same.
Not a quick/cheap job as you need new 590 rims (rather than 584). The brake would be ok so long as you can raise the pads by 3mm or so.

Just for clarity,
26 X 1 3/8"/590 rim is old "3 speed" 26" tyres/rims.
26"/559 rims is mountain bike 26" tyres.rims.
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andrew_s
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Location: Gloucestershire

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by andrew_s »

Use the ISO sizes. For a tyre marked 44-584...

584 is the diameter of the tyre at the bead, where it fits the rim.
Any tyre that's also marked as 584 will fit the rim, subject to width considerations.

44 is the height/width of the tyre (the inside of the tyre will be circular when it's inflated).
You can fit a tyre that's reasonably close to the existing tyre, so replacing a 44 tyre with a 35 tyre is OK, but if the old/new sizes are sufficiently different, you may find that the tyre isn't a good match to the rim width. If you put a narrow tyre on a wide rim, you'll find that the ride gets harsher, and if you fit a tyre that's a lot wider than the rim, the handling of the bike can suffer, as the tyre may push over sideways when cornering.
The widths that will fit a rim acceptably range from about the same as the external width of the rim, up to double that (for hooked inner tube rims at least - I've not played with tubeless). Note that the width marked on the rim itself is the internal width, which is generally about 6 mm less than the external width.

Sizes measured in fractional inches are a can of worms, and are best ignored in favour of the ISO 28-622 style sizes, There are, for example, 6 different and incompatible 26" sizes (iirc).
The common old French sizes (700C or 650B) can be taken as being the same as ISO 622 or 584 rim diameters. The 700 and 650 was the nominal outside diameter of the tyre, when on the wheel, and A/B/C were old standard narrow/medium/wide tyre widths.
Similarly 26" x decimal width (i.e. 1.5, not 1½) is a standard ISO 559 rim diameter, and 27.5" x decimal width is always ISO 584 (same as 650B)
Merida CX90_D-4 wrote: 17 Jan 2023, 6:11pm What then is difference on below as "35B" version doesnt have "1 5/8" ?

(650 x 42B-26 x1 5/8 x 1 1/2 )
( 650x35B-26x1 1/2 )
The first tyre inch size is incorrect. It should be 26 x 1½ x 1⅝".
26 x 1½ is the rim size. 26" - (2 x 1½") = 23" = 584 mm
1⅝ is the tyre width (about 42 mm)
In 650x42B, 650B is the rim size (584 mm), and 42 is the tyre width.

In the second tyre, the inch size doesn't mention the width, which normally should mean that it's the same as the nominal size used for the rim size - i.e. 1½" = 38 mm. If the 35 mm width on the 650x35B is correct, the inch marking should be 26 x 1½ x 1⅜"

Even the tyre manufacturers don't always get the fractional inch sizes correct :(, which is why I said to ignore them.
Merida CX90_D-4
Posts: 11
Joined: 28 Jul 2022, 4:20pm

Re: Help: rare'ish Tire size, and possible miss-labelled tire at Shop

Post by Merida CX90_D-4 »

Hi ! all

Thank you all very very much for the help and Detailled explanations. i will double save them all into txt and prt scr into my files.

I will go and buy the mentioned DeliTire (qty:2) at Thursday or Friday or at weekend. im heading to neighbour town tomorrow...

My mentioned Vintage bicycle would have been "Lost case" without all your help. Its not easy living in Rural area(s) and now i also saved much money, that i can spend to other Bicycle parts, thx to you all.

bye:)
m
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