Antique Harley Tires should fit 650b Bicycle Rims

[creebobby]

Hello all,
There was a discussion before about the Coker all white 28 X 2-1/2 button tread antique motorcycle clincher tires, and it was agreed that they wouldn't fit any bicycle rims.
In fact I think they would fit 650b rims, also known as Schwinn S-4.
Here's the math:
28 X 2 1/2 - the bead size is 28 minus twice the tire height.
28 - 5 = 23 inches.
23 inches = 584mm = the 650b size exactly.
This size was lost to obscurity but has recently made a bit of a comeback for mountain bikes.
The only trouble would be finding a rim that's wide and strong enough. Velocity makes the P35 (35mm wide) in a 650b size. Or, a pair of old tubular steel Schwinn S4 rims would be wide and strong, too.

With that said, I don't know if anyone's willing to bite the bullet and spend $650 on tires alone. I'd sure like to see it done, though!
(LIke maybe on a Sportsman Racer, hint ...hint... hint...)
Thanks all,
Jacob

 

[sportscarpat]

Hello all,

With that said, I don't know if anyone's willing to bite the bullet and spend $650 on tires alone. I'd sure like to see it done, though!
(LIke maybe on a Sportsman Racer, hint ...hint... hint...)
Thanks all,
Jacob

Well, I got a laugh out of that one! Seriously, though, it seems the Simplex 26 x 2.5 tire is the way to go. Still pretty pricey but half the cost of the Harley tires and it has been proven to fit a 26" bicycle rim.
Pat

 

[creebobby]

The Simplex definitely wins because it fits the standard 26 rim that everyone already has.
But it doesn't come in white!
After a trip to the HD museum in July, I've been obsessed with the 28 X 2 1/2 all-white tires, and dream of putting them on a BTR tribute.

Even though the Simplex tire is rated at 90mph, apparently all clincher rims pose an inherent danger at more-than-bicycle speeds - which is why they were largely eliminated from motor vehicles after 1928.

Here's an interesting article about the risk:
The Vintagent: 'BEADED EDGE' TIRES AND SAFETY

Basically, when under-inflated they can pop off the rim if you hit a bump at speed, resulting in a spill. And if they go flat at speed the same can happen - they can quickly tear from the rim and lock up the front wheel.
Probably modern bicycle rims (and tires) are much safer than the early thin sheet metal clincher rims, but perhaps the risk at speed is still there.

It seems that if the upgrade to Simplex tires is for safety (to handle prolonged speeds at or over 30mph) it might be a better idea to find a more modern motorcycle tire/rim that would fit the bill.