Photos from the Las Vegas Auction

[MotorbikeMike]

Hi guys, well tires, and rubber? It is true that natural rubber is white. The problem is that white natural rubber is very easily damaged by sunlight. "Dry-Rotting" tires were everywhere!

It was somehow determined that the latex rubber would be more protected if colored, and red was used early on, and used in inner tubes for a long time after. The decision finally was to use black, and the earliest that I have heard of was by adding simple Lamp-Black to the raw rubber.

The mystery ingredient turns out to be simple, pure carbon.

Mike

 

[OleSkool]

I really am interested in the leaf spring front and rear set up on the Jefferson!

Without custom ordering/fabricating leaf springs does anyone know where to get light duty leafs for a similar set up I thought about using some 1000# trailer springs but that seems heavy to even get them to flex when used on a motorized bicycle!

 

[chipmcluk]

I really am interested in the leaf spring front and rear set up on the Jefferson!

Without custom ordering/fabricating leaf springs does anyone know where to get light duty leafs for a similar set up I thought about using some 1000# trailer springs but that seems heavy to even get them to flex when used on a motorized bicycle!

You can use those springs but for such a light weight bike, you might want to use just one. Play with the length/fulcrum to get the spring rate you want. I scowered the junk yards to find a spring for my bike. Surprisingly, the thinnest spring I found came off of a jeep wagoneer! I just ripped it to get the width I wanted. Already had a decent curvature. Not much of a hassle to get the outer bend either. But if you heat it with a torch, it'll have to go back for heat treatment!

 

[dmar836]

For those interested, there are links to info about the Jefferson and the builder in this Vintagent blog entry.

the vintagent: LAS VEGAS, BEHIND THE PODIUM (PT.3)

Dave
KC

 

[Board Track Racer]

Dave, Thanks for posting this link. Very interesting.

 

[Mr.B.]

Interesting discussion!

Here’s some pictures I took at last years Davenport show...

A Pope with rare original 26” wheels and a Comet that has the same fork setup as that Jefferson B-tracker, 'Til now I’d never seen it on another.

-Kirk

 

[Bikeguy Joe]

I assume that's because white is the natural color of rubber once it's processed... only later it became black, I assume they put in the compound something to change the color, probably because white was too labour-intensive to keep... white!

I believe they put carbon black into the mix to give the rubber more body and strength....think very early "carbon fiber".

 

[Bikeguy Joe]

After posting, I saw Motorbike Mike got to the answer already.

 

[diegom]

A Pope with rare original 26” wheels and a Comet that has the same fork setup as that Jefferson B-tracker

now, maybe everybody already knows that (I'm always the last kid on the block!), but I just realized that when talking about veteran and vintage motorcycles, when they say they had 26" or 28" wheels, they're actually talking about the OUTSIDE DIAMETER OF THE TIRE!!

coming from the motorcycle world, every time you talk about tire size, you refer to the RIM diameter... not so for the older bikes with clincher (beaded edge) rims... the quoted figure is always the overall size of the wheel (rim+tire)

so a 26" wheel has a 20" or 21" rim depending on the tire section, a 28" wheel has a 22" to 24" rim...

it's all very clear on the Coker Tires catalog:
Antique, Vintage, Muscle Car, Hot Rod, Street Rod, Military Tires

page 35 for the tires details, where for each tire it gives the rim diameter it goes on, and 41 for the clincher rims...

again, maybe I discovered lukewarm water here...

ciao

diego