# 700c to 700a tire surgery *For display only... do not ride



## JHRIII (Jun 15, 2020)

Since the tires on my 1909 Cycles Gladiator weren't original, in pretty bad shape and I wanted to install white tires in tradition of resemblance to originality, I went on a hunt. Seeing some tires I liked on an Argentinian Facebook page, I unbelievably found one dealer in the US selling them... for $10 a set (yes, 2 tires for $10 + shipping). They were stark white so I tore off the nipples, sanded the leftovers from the tire mold off, and brushed them good with mud. Happy with the results, I learned upon  my reluctance of assumption, I missed the fact my 1909 Cycles Gladiator has 700a wheeles (ETRTO of 642 vs 622 on the common 700c).



Upon my search, I soon learned finding these tires isn't easy, and not cheap when you do. Due to a bottom bracket shell repair and too many other projects, this bike isn't going to be a rider anytime soon so I started thinking. I used to be the North American manager for CST (Cheng Shin Tire, parent company of Maxxis) so I know way too much about tire construction and since I invested a whole $10 in tires I couldn't use, I decided defeat was not an option (until I can find some proper tires for it.



*Warning, not for the purest





Here is the tire as it sat new (prior to me checking the actual size of the original tires). After seeing how stark white they were, I decided to 'age' them. The nylon used in tires today resists a lot of things like tea so I ended up heading to the back yard and using a stiff brush to grind a bit of age into them. See the following pics for results.




I started by cutting the inside of the casing close to the edge where the wire bead sits. Since the wire bead is bonded in during the curing process, I knew it wouldn't go smoothly. (the 4th bead was easier after learning from the first 3 tries).




Pulling the bead out on my first try was tricky without pulling too much meat out with it, but then it dawned on me...




A wire bead in a tire is one single piece of wire wrapped around about 5 or so times. If you grab about any tire with a bead, you'll notice a small lump. That is where the two ends of the wire are taped together before being placed in the mold. If you start there, you can then take unwrap the single wire which leaves a much cleaner cut. Worth noting, to get it started, it helps to bend the bead to make it poke up. from there you can use a small flathead and/or pliers to get it started.




After the wire is out, you have what is a really floppy folding tire. Notice, the outside bead is still fully intact but without the structure to keep it from stretching. So did it fit?




For display, it fits fine. It will only hold enough air to give it shape (maybe 10psi max), as anything more, the tube will pop out the side. (in other words, don't try to ride it).




Overall, I am pleased with the results until I find proper, suitable replacements. I also added Orange Seal tire sealant to the inside of the tubes so they will hold air MUCH longer without having to re-inflate as often.


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## Kombicol (Jun 16, 2020)

Black and gum wall 700a tires are not too hard to find
White I have not seen available


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## JHRIII (Jun 16, 2020)

Kombicol said:


> Black and gum wall 700a tires are not too hard to find
> White I have not seen available



This is what I've seen... But even the black ones were priced high enough to sway me from buying them vs waiting for some white ones to o e day magically appear. This was a good compromise on the meantime... but very much a compromise.


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## Kombicol (Jun 17, 2020)

Could you fish a wire back in the bead at the new length now you have stretched the rubber?


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## JHRIII (Jun 17, 2020)

Kombicol said:


> Could you fish a wire back in the bead at the new length now you have stretched the rubber?



No, it would be impossible to do. The bead is placed in the mold during the construction of the casing and needs that casing structure (not just rubber) to hold it in place


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## 49autocycledeluxe (Jun 17, 2020)

what did removing the bead do?   is that the only way to get the tire on the rim?

cool bike!


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## Waffenrad (Jun 17, 2020)

A 700A rim is a really big 642 mm diameter rim.  A 700C tire is much smaller, only 622 mm.  A traditional 28 x 1 1/2" roadster tire is closer in size to the 700A, at 635 mm, and I have found them in both white and cream.  They usually have the traditional English roadster tread.


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## JHRIII (Jun 18, 2020)

49autocycledeluxe said:


> what did removing the bead do?   is that the only way to get the tire on the rim?
> 
> cool bike!



The bead is what keeps the rubber/nylon tire from stretching past the rim wall. Removing it allowed me to get over that whopping 20mm larger diameter wheel. It is absolutely not safe to ride like this but as stated, this bike is not currently ridable regardless of the tires.


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## JHRIII (Jun 18, 2020)

Waffenrad said:


> A 700A rim is a really big 642 mm diameter rim.  A 700C tire is much smaller, only 622 mm.  A traditional 28 x 1 1/2" roadster tire is closer in size to the 700A, at 635 mm, and I have found them in both white and cream.  They usually have the traditional English roadster tread.



If only a 635 would fit, my life would be a bit easier.  So funny story, but while at Maxxis/Cheng Shin, I was responsible for everything including all catalog & web content. Outside of the branded tires, we sold a ton of tires to other brands to relabel... Including those with the 635 ETRTO (some countries still sold them). Product photography involved placing tires of over 200 tread patterns on rims and inflating to shape. I had to do the 635s last because I had to ziptie the tire to two places on the rim then use tape to wrap around the tire & tube that we're exposed. It was a head scratching moment that worked but was frustrating to realize this during such an exhausting project.


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## Cooper S. (Jun 18, 2020)

So how long until you take your knowledge of tires and make some new tubulars for wood rims??


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## JHRIII (Jun 19, 2020)

Cooper S. said:


> So how long until you take your knowledge of tires and make some new tubulars for wood rims??



Ha! I am not an engineer nor do the factories I've worked with do small batches. I'm sure someone with the right experience & tools (also time and money) might could retrofit tread to a proper casing though.


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## gkeep (Oct 20, 2020)

Kombicol said:


> Black and gum wall 700a tires are not too hard to find
> White I have not seen available



There are gumwall 700A ISO 642 tires out there? Are these clinchers? The only true 28", ISO 642 clinchers I've found for my Pierce are the V Rubber tires available from Moruya in Australia. https://www.moruyabicycles.com.au/contents/en-uk/p393_Vee-Rubber-Tyre-28-x-1-3_8.html. Wish they came in cream or white. Wish someone in the US would import them, shipping is twice as much as the tires.

About 5 years ago I emailed V Rubber's North American headquarters asking about 28" tires but never got a reply.


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## Kombicol (Oct 20, 2020)

Yup

https://rover.ebay.com/rover/1/705-...0001&campid=5335809022&icep_item=263834267209


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## dnc1 (Oct 22, 2020)

You might want to try:









						Pneus 700A Standard- 37-642
					

<p>Le pneu <strong>700A</strong> correspond pour un montage sur les <strong>roues d'anciens vélo</strong> nommées "<strong>Chapeau de Gendarme</strong>" ou roues en bois.<br></p><p><strong>De couleur noir, sa dimenssion: 28 x 1.3/8 -  ERTRO est: 37-642. 700A</strong></p><p><strong>Produit neuf...




					www.labicicletta.fr
				




Currently selling for 19.90 euros each.
Not sure of postage costs to the USA though.


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