Two Wheels - Six Strings

Random news and thoughts about various two-wheeled projects and music, especially my band, Skull Full Of Blues.

Saturday, February 17, 2007

Iver Johnson Progress

Year before last, I picked up this Iver Johnson truss frame. The wheels were missing, and it was cosmetically rough. Plus the seat tube had, at some time or another, been broken and the repair looked as though it had been done by a blacksmith...a drunk, near-sighted blacksmith. Had it been in better shape, I would have sold it to someone who would restore it (not something I would be interested in, myself). But I figured it was too rough to be worth that kind of expense and effort, so I decided to build the equivalent of an automotive street rod. I wanted to retain the vintage look (the frame was manufactured somewhere between 1905 and 1919, according to the one website I could find with info), but use some more modern components in the interest of performance and economy.

So, I started to look at what it would take. First, the fork doesn't have slotted dropouts. The axle fits through holes in the blades. I stuck a wheel in it, and just let me say I certainly wouldn't want to have to do that on a regular basis. I decided to get a chrome fork and swap it out. (I had decided to try and replicate the look of the centerfold bike in the book The American Bicycle, by Jay Pridmore and Jim Hurd. That Iver Johnson has a nickle-plated fork and a really cool copper-colored paintjob.) This had the added benefit of allowing me to mount a front brake. I intend to ride this bike on public roads, and I am just not comfortable riding without a brake.

For all of the "brakes are for sissies" guys:
you're reading the wrong blog. www.oldskooltrack.com is elsewhere.

I didn't figure I'd be able to get usable wooden rims, so I decided to just go with some track wheels and 35c tires. I also purchased a steel track bar, cork grips and a leather saddle for it.


The drivetrain used an inch-pitch chain (missing, along with the cog, of course). The rusted hulk of a chain which came with the frame wasn't the correct pitch, so I looked into getting an inch-pitch chain and cog. But, I decided not to at $275.00 - they haven't been produced since 1930.

So, I thought I might just run a modern, half-inch pitch chain on the old chainring, but that didn't work out. Half-inch pitch chains are spaced at precisely 1/2 inch (imagine that!), but inch-pitch chains are not spaced at an even inch. So, the chain only wraps part-way around and then starts riding up on the teeth.


Look closely, and you can see the chain riding up on the teeth.

Keep in mind, that all of this discovery was made over the past 18 months, or so. This has been a long-term project.

Anyway, I figured I would pull a one-piece crank from an old Schwinn I had lying about, and just run with that. Sounds like a good plan; huh? All I had to do was to swap out the fork, crank and bottom bracket, build it up to make sure it works, then paint (or powder coat it) after getting the lumpy brazing on the seat tube smoothed down.

Funny thing is, "standard" sizing in the American bike industry has changed somewhat in the past 100 years.

For instance, the bottom bracket shell won't accept the Astabula one-piece bottom bracket or crank. It is too wide for the crank spacing, and the diameter is too small for the bottom bracket cups. The head tube is too small for a BMX-style headset, and too large for a 1" road headset.

So, I was back to using the stock crank. I hoped I could swap chainrings with the Ashtabula crank. Of course, the mounting hole on the more modern chainring is too small to fit on the old crank, and the locating tab on the crank doesn't line up with the hole on the ring. Determined, I broke out the Dremel, and enlarged the mounting hole, then cut a slot for the crank tab.
Moving on to the fork (onto which the original headset bearing race wouldn't fit), I shimmed an old Shimano Dura Ace bottom cup into the frame, then just used the top half of the original headset.All of the crank work and headset messing-about happened tonight. Once I got to that point, I stuck the wheels and tires on, then sized up a chain. Not done yet, obviously, but it's getting to the point where it looks like a bike, anyway.
x

6 Comments:

At 2:19 PM , Blogger B said...

I came across your Iver Johnson Build in your blog and want to know if you still have the original fork for it. I need one for the Truss frame I just bought. Please let me know if you have it and are interested in selling it. Nice looking bike btw!

 
At 9:22 PM , Blogger Jon said...

I believe I do. I just saw your comment, and it is a bit late to go digging through my shop. Email me at jjgrinder msn com (add the correct symbols, of course) and remind me to look for it.

 
At 9:31 AM , Blogger B said...

Hi Jon, I just emailed you about the fork! Let me know if you're interested in parting with it.

Thanks!
-Brian

 
At 9:33 AM , Blogger B said...

Hi Jon, I didn't see this for a bit, but I'm interested in the fork if you'd like to part with it as well as the old chain ring. I emailed your msn account.

 
At 6:27 AM , Blogger Wally Estrella said...

Late to the party ;)
Curious if you still have the chainring? If so, interested in selling? TY, w.

 
At 7:02 PM , Blogger Jon said...

Wally, I sold the chainring along with the fork, a while back. Sorry.

 

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