Tire-making - cont'd from Heritage Lane

[DougC]

Some time ago I started a topic about trying to make tires in the Heritage Lane forum.
http://www.motoredbikes.com/showthread.php?t=23988
I have elected to continue it here instead, since it is really about just tires.

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It has taken a while for me to get this far, but it is moving along.

http://www.norcom2000.com/users/dcim...ng/test04.html

The page above has two links, with the initial newsgroup posts about each--I usually talked most about this on rec.bicycles.tech.

The first (casing test page) is the machine that makes the casing fabric, and that machine is pretty much finished at this point.

The second link (bead machine page) is the start of the bead-setting machine. That is still in progress, but looks to be going as planned.

The next machine needed is one to put thread on the tires. That is not yet begun at all.


This project started out as a desire for better vintage-style bicycle tires than what could be purchased. That is part of the plan but since then I have realized that there's other interesting possibilities also. I don't want to go into them too much but I will say two things now:

1) there will be "standard" models with set color schemes (casing and treads were often different colors) but one obvious possibility is allowing customized colors: a customer would send paint samples with the order, and the tires would be colored the same colors they want. This wouldn't just be something painted on the outside; the rubber would be colored all the way through.

2) another I'll say now is that custom colors or not, they're not going to be cheap. China can make a bicycle tire for less than $1 and wholesale it for under $5, and somebody else can retail it on Amazon for under $10. There's no way I could do that, or even approach it. I dunno how much they'll end up priced at, but they're not likely to be bargain purchases.

[DougC]

Just for something to look at: I don't think I've seen this link posted here yet.

On the newsgroup I asked a question about how to estimate bead wire strength, and it was pointed out that the bead wires do not experience direct tension in use. They mainly form an incompressible thick edge that will not pull out between the innertube and the hooked edge of the rim. This can be proven by cutting the wire bead (even in multiple places) and the tire will still stay in place, when mounted properly.

One page showing such a test:
http://www.sheldonbrown.com/rinard/tirebead.htm



If there is anything slippery on the rim edge during tire mounting, then the issue can fall back on direct bead strength to hold the tire on. This is the problem that a lot of people doing tubeless MTB conversions experience--when the non-tubeless tires pop off the rims.


Older tires (fractional rim sizes) did not have hooked-edge rims, and so relied more on wire bead strength--but the main factor was still usually just friction of the tire's edge on the inside of the rim.

[loquin]

Doug - one point that I just thought about is this: With tires, and a tire company, since their failure could be catastrophic, be very, VERY sure that you're insured well, and preferably, that you set your business up as a Corporation or LLC, before a single tire is sold, or tested, in order to separate your personal assets from any corporate assets.

With a sole proprietorship or partnership, if the business is sued, your personal assets are considered to be part of the business. From a legal viewpoint, there is little to no separation between business and personal assets.

However, with a corporation or LLC, unless personal negligence on your part can be proven, your personal assets are protected. The corporation could be levied hard if the corporation were sued, but you, personally, would not be forced out of your home/penniless...)

Side note - be sure to offer an option for tires with no tread at all... just a slick rubber surface. it offers the most traction under almost all road conditions (dry, wet, icy, etc.) (offroad is another issue, but on pavement, slick is the best)

[happycheapskate]

That is an interesting point about the tubeless conversions. I get asked a lot why I still "bother with" tube tires. It works, its cheap, and it's familiar. I hope your niche-market tires take off well, really do. I think it's awesome that this board is helping people launch businesses, and some people still want to mfgr products even when it's hard.

I'm interested to see the test with the broken bead tires staying on the rim. My experience with tires has been if the bead stretches or breaks, it's a goner, fast! Same as with any cords that are cut at the intersection of the bead wires: the tire gapes open and the tube is slashed, esp if it hits a rim brake. The old style tires (non hooked beads) are useful and cheap, but don't offer high-psi versions for a reason. Overinflation (even once) usually dooms these tires quickly, even though sometimes they look "normal".

[DougC]

...With tires, and a tire company, since their failure could be catastrophic, be very, VERY sure that you're insured well, and preferably, that you set your business up as a Corporation or LLC, ...

I am aware of the LLC issue.

The slick tread styles will be possible anyway--but for typical bicycle (or motorized-bicycle) use the issue of their greater traction usually isn't significant. Most bicyclists do not accelerate or corner anywhere near the limits of tire adhesion, and the right tread pattern can reduce the rolling resistance and increase puncture protection considerably.

... I'm interested to see the test with the broken bead tires staying on the rim. My experience with tires has been if the bead stretches or breaks, it's a goner, fast! Same as with any cords that are cut at the intersection of the bead wires: the tire gapes open and the tube is slashed, esp if it hits a rim brake. ...

Before the advent of kevlar beads, there were companies that made "folding" bicycle tires by using a bead that was a series of short (~1" long) thick wire sections instead of one big loop. It was foldable anywhere between the wire sections. The problem was similar to what you mentioned though--if any of the casing threads got damaged near the ends of the wire sections, they would tend to unravel enough for the inner tube to poke out through a hole near the rim.

There is also really three different kinds of bicycle tire beads now: the old solid-wire ones (very stiff), the kevlar ones (fully foldable) and the wire-rope ones, which are semi-foldable (as long as you do not crease the bead wires).

The tires that come folded up into little boxes (at Wal-Mart for one) are tires that use wire-rope beads. The wire rope is ~.035" cable, wrapped 2-3 turns around each bead.