I thought some of you would know. I am interested to create a bike with a geometry as close to the following bike as possible. So, the type of mounts and mods do not really matter, which is what most of the articles I read are talking about.

I need to know what has changed in dimensions of the frame since then.

For example Ironheads to Evo. The frame is taller, from what I gather?

What about Ironheads all the way to 1957, did the frame dimensions change at all?

This appears to be 79-81, I cant find the 57 dimensions.

 

Here is a scan from my factory HD repair manual (57 thru 69). Hope this helps.......... Still working on my front wheel and chain guard, other than that I'm pretty close on this one.

 

Yes, that helps alot. Thank you Joe.

Yours appear to be identical or very close to this one which says 73 or after:

 

Joe, are you building a 57 sportster?

 

The frames from '57 to '78 were very similar (some minor changes along the way) The big change was in '79.
What exactly are you trying to build?

 

AJ,

I want a bike as close to the 1957 sportster ( in looks and geometry, not the performance) as possible.

So, I should be able to base it on a sporster within those years? What would be the most challenging part of project do you think?

 

So, anyone has made a replica of that model around here?

 

Well, you could start out with anything '78 or older as far as the frame. How close to the '57 does your final product have to be? How much do you want to spend. Do you have to have the drum front brakes? They were stock up to '72, but many of those have been converted to disc. Not sure how hard it is to find that style fuel tank...I'm sure they're around, but with a good price tag. The rear fender (K style) are around but also pretty salty.

I would say, for what it "seems" like you want, to look for a '72 or older that is fairly stock and change out the tank, the rear fender and put the bigger head light on and you'll be pretty close.