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I have to replace another set of 700-17 tires and face the problem of tubes. A decade ago I replaced these tires with Coker Firestones and the only tubes available were the multi-size that supposedly fits 700-17, 750-17, 700-18, and 750-18. After the first 100 miles both fronts went flat simultaneously. I took them to an installer with much more tube experience than the first, they told me the tubes were too big and had gotten folds trapped. I did a bunch of searching to find a smaller tube and ended up – I think – with tubes for a light truck tire 8.00R16.5LT and 8.75R16.5LT. Unfortunately I don’t remember for sure. Those have been on ever since.
I don’t know how much the improvement is due to a more experienced tube tire installer or the slighter smaller size fitting better.
Has anyone else had this issue with the multi-size tubes on 700-17’s?
Thanks, Jim
Lucas Tires in Long Beach, Calif installed my tires about 10 years ago and I have had zero issues with flats or any other tube problems.
Give them a call and see what they have to say.
Lucas Classic Tires
(562) 595-6721
I will be putting new tires on my car soon, and it has slightly larger tires than yours, 7.50 x 17. I have been told by numerous club members to put 16 or 16.5 inch radial truck tubes in the tires, for exactly the same reason, folds getting trapped.
Thanks, I think that confirms the size I found before and others having the same issue!
Jim
The drop center rims of the 17″ rims is about 1″ deep. So with a 17″ tire/rim, the drop center is actually about 15″ diameter. This deep drop is needed to allow the semi-rigid bead of the tire to be pulled into while the opposite side of the tire bead is stretched over the outside diameter of the rim.
Problems occur when a 17″ tube is inflated in a 17″ tire. The inside diameter of the tube is close to being the same 17″ as the bead of the tire. But in order to inflate the tube to 40psi which is needed to support the weight of our cars, the tube must expand fully and be fully inflated inside the tire and the rim. Including the drop center of the rim. When a 17″ tube is inflated so that it expands down into the drop center, the tube wall is stretched very thin, and failures will occur at seam-lines or rough spots on the rim’s surface.
All wheel rims from the 20’s and 30’s had some form of rough surface on the inside surface. Such has the end of a wood spoke, or the tensioning nut for the wires of a wire wheel. The Kelsey Hayes 17″ and 18″ drop center wheels on ’32 and ’33 and up Pierces had welded spokes and the end of the spokes were in a recess or dimple in the drop center. So the surface was similar to the surface of a golf ball, all dimpled.
When new, with only paint on the surface and no rust or rust pits, the inside of the rim could be separated from the surface of the inner tube by a thin, flat band of rubber. Much like a loop of tape with the ends bonded together. This thin layer was adequate to smooth out the dimpled surface so that the inflated inner tube was not abraded by the steel surface.
But today, most if not all rims will have at the least some rust on the inside of the rim, and the drop center surfaces. This rusted surface, even when carefully cleaned, sanded and painted, is rarely as smooth as the original painted steel when it was new. The surfaces need to be smooth in order for the inner tube to slide against the surface as it inflates. If an inner tube catches against a rough surface, the ‘snagged’ area will cause additional thinner sections of rubber inner tube to occur around it. This creates even more opportunities for inner tube failure.
When installing a set of new tires on drop center rims a few years ago, the wrong size ‘bands’ were received to cover the wire-wheel spoke-ends in the bottom of the drop center. When I called Coker, the person I spoke with said that they recommended not using the bands anymore. They recommended using PVC tape to cover the sides and bottom of the drop center, creating a very smooth and slick surface for the tube to slide against and rest against when inflated.
I had not heard of PVC tape at that time, I asked do you mean tape like ‘Duct Tape’. The Coker rep was adamant that Duct Tape was NOT what he meant. Duct tape has a woven fabric core, with low temperature resistant plastic and adhesives. According to the Coker rep, Duct Tape had caused or aggravated many tube failures for them. The tape softens with the heat generated by the tires and wheels, then the tape ends up in balls of goo, causing stretched tubes and exposed rough wheel surfaces.
The Coker rep said that PVC tape was available a good Plumbing and Heating suppliers. HVAC stores or suppliers usually carried it.
I found a supplier of the PVC tape and found that it is a very good product for covering the steel drop center of our wheels. It is slick, strong, easily conforms to the compound curve of the sides of the drop center, as well as the flat bottom of the dropped center.
In the photo, I show a 17″ Kelsey Hayes Pierce wheel, it was wire-brushed, then sand blasted, then primed with a 2-part epoxy primer-sealer. Then I applied a strip of PVC tape around each side of the drop center, then a third layer around the bottom of the dropped area. Care must be taken to not get any tape over the corner where the bead of the tire will slide. The bead of the tire will not be harmed by a slightly rough painted surface on the bead area of the rim.
I will be writing a service bulletin for David White and Arnold to publish soon. I will have several photos and a sketch or two to make the bulletin easy to understand and follow if desired.
Greg Long
i
Bravo, Greg! I was one of the first beneficiaries of your concerted research. This occurred as a result of two flats on my 1934 at highway speeds in very hot weather (first was 106* F in the Mojave Desert, second was a day later at 88*F south of San Jose returning from the 2009 Temecula Meet) with brand new 17″ tubes and tires installed on cleaned and painted interior surfaces of the wheels.
Both tubes let go on the bonded seams which were not in contact with the dropped center. Replacing the first tube in Bakersfield, we used a 16″ truck tube primarily because no 17″ was available, but also reevaluated what the drop center means to tube size.
As soon as I returned home, I replaced all 17″ new tubes with 16″ radial light truck tubes, although the tires are correct bias-ply, and have had no further tube difficulties in 10,000 miles.
Thanks to all.
I really appreciate that there are companies supplying the wide range of low production antique tire sizes, however it is a bit frustrating if they know the flaps and tubes they recommend have problems.
It was probably covered a few years ago, but the original tubes were much more robust. 25 years ago when I needed to get tires on my Pierce the installer pulled out the old tubes. He was a bit of a tire nerd and told me one of the tubes was probably original as the Goodyear symbol on the side was a style discontinued ca 1936. That inside diameter that rides on the inside of the wheel was semi-rigid,molded somewhat to the shape of the wheel and perhaps 4 times thicker than the outer part of the tube. It was also a safety tube with a tube within a tube to not run flat if the outer tube looses air. I don’t know if P-A supplied these as original equipment or perhaps it was a premium tube added after a flat ca 1936. Too bad we can’t get those!
Jim
Hello George,
Would you please advise the name of the supplier you obtained the light-duty radial truck tubes from? And where were they made?
We plan to follow Greg’s recommendation and have already obtained the high-temp HVAC tape; but there’s no point in replacing thin Chinese tubes with more of the same.
An old car friend who owned a Goodyear store years ago also recommended using generous amounts of talcum powder when the tires are being mounted onto the rim.
We’ve had 3 flats on our ’36; one more and I might just qualify for an Indy pit crew!
Thanks-Stu
Stu, got mine from my local Big O dealer from whom I buy tires for my pickups. Don’t recall the brand–that was 9 years ago. Suggest you buy one or two extra tubes, which will prevent you ever having to use one. 
Most drugstore “talcum” is NOW actually cornstarch rather than talc due to medical issues arising from talc, so it’s better to find “tire talc.” Check the labels on drugstore talcum powder. I still have some “real talc” talcum powder in the shop from the days before its ban for personal use. And I’ve bben using it for many decades. Likewise, be sure to inflate, then deflate, new tubes before inserting the tubes into the tire carcasses.
Last year I spoke to a company (Bratten’s) that sells a large amount of Ford (models A and T) parts regarding tubes. Knowing the tubes they sell are too small for our tires and wheels, I just wanted to get some information from them. It turns out they have their tubes custom made to their specifications. Clearly one needs to purchase a large quantity (thousands). Considering the high percentage of failures of current tubes and the fact that driving our cars is a major part of our Society, would having tubes made to our specifications be another item the Pierce Society would consider undertaking? We might be able to sell some of the allotment to other clubs or to other CCCA members. Just a thought.
Robert
I recently bought some radial 16″ tubes off of eBay, the very reasonable price was just too compelling.
BUT I gently inflated each tube, inside an un-mounted tire, to see what shape and size the tube took on when lightly inflated in just a tire.
My results showed that the tube properly filled the inside of the tire carcass, and the inside diameter was roughly 16″ – 16.5″ this was perfect for me..
Then I inflated one of these tubes on a naked rim, to check that it would properly inflate into the drop center.
Obviously I would need X-ray vision to truly see how the tube fills the mounted tire with 45PSI in the tube, but what I did see let me feel comfortable with using these tubes in the tires on my ’32 Convt Coupe that toured at the 2018 Annual Meet.
As mentioned above, partially inflate a tube, enough to get the tire to seat on the rim, then deflate the tube, I like to bounce the tire violently, the intent to shake the deflated tube so it will straighten and unfold any possible wrinkles or overlapping parts of the tube. Then reinflate.
Greg Long
George,
Thank you for the talcum powder information; “tire talc”” is available through NAPA and other auto parts stores.
Stu”
Stu,
I get my 16.5 radial truck tubes at a LOCAL primarily commercial tire shop and use them on 7.50 x 17’s in both wire and artillery wheels.
Anyone in that business should have what you need at a very reasonable price. Also get plastic inserts to snugly fit the stems to the opening in your wheels. Now the only flats I get is from driving over nails or other metal debris.
Dave
I’d like to emphasize Dave’s suggestion to add the plastic inserts to adapt the much narrower modern stems to the larger stem holes in our wheels. Tire stores which do a good amount of truck service have them.
And Robert Brown’s suggestion of having tubes specced and made for us, possibly through Bratten’s, is intriguing. Probably the most popular size for Pierce members would be 700/750 x 17, taking into account the drop center, and 650/700 x 18 a close second.
I picked up 7.00R7.50LR16LT Firestone branded tubes (probably still made in China) at the local Les Scwab dealer (and took them to a different installer). Firestone catalog lists this tube as fitting a number of 17″ radial as well as 16″ wheels. One I saw source says radial tubes can be installed in bias but tubes for bias can’t be installed in radial.
If anyone actually got some interest in manufacturing original type tubes, I still have the 1935 heavy safety tube in my garden shed for reverse engineering, couldn’t bear to part with it. Doubt if anyone is willing though!
Jim
Greg, would I follow the same procedure with my wooden artillery wheels? Putting the PVC tape on the metal rim?
Amongst the 16″ tubes being produced there are various stems, some come with a TR13 which is designed for a .53 rim hole and requires a bushing when used with a wheel using a larger .625 hole. The Firestone catalog states: “B6 bushing must be used with a .625 rim hole or valve failure will result”
When I picked up my tubes I expected them to be the TR13 but upon inspection were TR15 valves for the larger .625 hole, so the bushing wasn’t needed but Schwab had them in stock had they been required.
Jim
Hi Jim,
Today, I called Firestone / Bridgestone Tube in Russellville, Arkansas.
Their p/n 534-099 which is a light-duty truck 7.00R7.50R16LT tube with a TR-15-CW valve stem is made in Russellville, USA!!!
See page 2 of their current catalog – direct link attached.
http://www.firestonetubes.com/
Thank you for the lead, Stu
Tube update: Firestone does not sell retail/direct, but their customer service person referred me to one of their dealers who was very helpful in expediting my order – GCR Tire, Ashtabula, Ohio, (440) 992-4406, I spoke with the manager Shawn Herron who quickly processed my order for one box of 10 tubes (this is Firestone’s minimum order qty.) p/n 534-099.
Total with Ohio sales tax (I’m subject since I live in OH) was $224.18 and that includes free shipping for this drop-ship order coming directly from Firestone in Russellville, AR.
Ken: any drop center rim with anything but a smooth solid steel surface where the tube will expand against is a potential place to use the PVC tape. The tube needs a slick surface to slide over as it expands to fill the drop center rim.
Also, the tubes last longer when they expand against a smooth surface, like the smooth insides of the tire itself. So if you can make the steel rim smooth like the inside of the actual tire, this is a good thing.
Greg Long