1912 Harley - distance between top rails?

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MarkV

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Jun 14, 2010
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Austin, Texas
Howdy Fishguts,

Take a look at the plans here:
Harley-Davidson's Lost Designs | Motorcycle History | Motorcycle News



Here's a link to the guys who apparently have the original plans.

According to the caption on the website, the plans are "1911", so they might be for the 1911 or the upcoming 1912 bikes. They also state that they are for the 6 1/2 HP model. - I am not sure which specific model you are interested in.

The resolution is too poor to read the dimensions, but by importing the image into my "Perspective Rectifier" software and assuming the wheels were 28" in diameter, I can electronically re-establish the plans in full scale and take measurements. It appears that the distance between the two top rails was 4 7/8" measured center to center. The tubes scale out to 1 1/4" diameter, leaving a gap between them of 3 5/8". - Just let me know if you'd like more help with the dimensions. The software can also work from old photos if they are clear enough and there are a couple of known dimensions, although the precision can suffer a bit.

PS - Note that there are two more pages with early Harley-Davidson plans, here and here.

MarkV
 
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fishguts

New Member
Sep 7, 2010
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southeastern MA
Wow, Mark, the information and links you provided are great!..more than I hoped for, actually. This will give me what I need for the Harley tribute bike I'm planning. My wife's great uncle owned a 1912 version in 1914 which he bought used. I believe he was also the guy who was a mechanic at Indy about the same time.

Hope I don't get in trouble for posting a photo of my wife's grandmother standing beside her brother's bike (I posted it in another thread, too). This photo is the inspiration that got me into the MB thing.

 

MarkV

New Member
Jun 14, 2010
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Austin, Texas
Glad to help.

That's a great looking bike. It really makes it meaningful when you can relate your tribute bike back to a historic bike that was in the family.

I am a history buff myself and have tried to find a historic motorcycle in the family tree, but have struck out so far. The closest I've come is my great grandfather who started out as a carriage maker in Ohio around the turn of the last century and worked for or with several of the automotive pioneers in Illinois, Michigan, and Indiana during the first decade of the 20th century. I have tried to find a link between him and the many motorcycle companies that were in these areas at that time, but with no luck so far.

MarkV
 

fishguts

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Sep 7, 2010
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southeastern MA
If he worked in the car industry in Indiana, would that be Studebaker? The Studebaker brothers started building wagons on a farm right down the road from where we used to live in PA.
 

dmar836

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Jun 23, 2009
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KC
Fishguts,
Mark has given great resources but remember that 28" is a nominal size of ???? For example, a 700c wheel is not 700mm nor is that the outside diameter of the mounted tire. A 26" rim is about 22.75" and, with the tire, can be a whole range of OD sizes. I have done this extrapolation in the same way but just keep that in mind when starting from images. Also, and maybe more importantly, Harley(not sure if the year in question) and a few others used 26" rather than the commonly assumed old 28" wheels. You might want to check on it.
Good luck!
Dave
KC
 

MarkV

New Member
Jun 14, 2010
20
1
0
Austin, Texas
Fishguts,
Mark has given great resources but remember that 28" is a nominal size of ???? For example, a 700c wheel is not 700mm nor is that the outside diameter of the mounted tire. A 26" rim is about 22.75" and, with the tire, can be a whole range of OD sizes. I have done this extrapolation in the same way but just keep that in mind when starting from images. Also, and maybe more importantly, Harley(not sure if the year in question) and a few others used 26" rather than the commonly assumed old 28" wheels. You might want to check on it.
Good luck!
Dave
KC
Dave,

Good points. 1911 Harley-Davidsons were available with either 28" or 26" tires. I haven't found conclusive info about the tire sizes available on 1912 single cylinder models yet. In scaling the plans I assumed that 28" was more likely the case than 26" because I thought the frame would have been designed for the larger tire, and so that would be more likely to be what was drawn on the plans.

I am definitely no expert on tires, but from what I've read online, the earlier the tire the more likely it is to have been near its nominal size. Apparently tire sizes began to significantly depart from nominal in the 1930s when tire manufacturers began to offer narrower tires designed to fit the standard rims. These narrower tires were shorter as well.

I checked a few books and it appears that the frame seen in the "1911" plans is actually a 1912 model - the 1911 frame didn't have an angled top tube. The plans are probably dated 1911 and therefore were for the upcoming 1912 model.

The numbers for the frame dimensions that the software generated based on 28" tires appear reasonable to me. If any one can come up with a more definite dimension on the plan that I can scale from, I'd be happy to run the numbers again.

MarkV
 

fishguts

New Member
Sep 7, 2010
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southeastern MA
The good thing is I'll be building a tribute bike similar to the appearance to a '12 Harley but not an exact replica. This means I can fudge on the measurements quite a bit. My question about tube spacing comes from finding a frame with a nice lower rail shape that meets the bottom bracket in a way that it kinda looks like a drop loop frame but really isn't. So with this undropped loop, stock wheelbase and right upper tube proportions it should look pretty good even with a peanut sized engine.

What I'm doing is starting with a girl's bike frame, cutting out the top tube and welding in two new tubes, one straight and one with a Harleyesque bend in it.

Actually, the MB I'm building now is intended to look like a brass era motor bike, but it isn't a copy of anything in particular. It's using a modern Micargi frame. The next one, however, will have a heavier/better frame profile with the 40's frame I'm using.
 
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MarkV

New Member
Jun 14, 2010
20
1
0
Austin, Texas
Fishguts,

Personally, I think the Worksman Industrial Newsboy with the Monarch front fork looks a lot like the 1912 Harley Davidson. The Worksman IN has a curved top tube, has lugged frame joints like the 1912 Harley, has heavy-duty wheels, and the spacing on the top tubes is about the same (3.5" clear between the tubes). I've been thinking that if you start with a Worksman and then clamp on a curved front frame tube taken off of a girl's bike, you'd be a long way towards a faux drop loop Harley, all without the necessity for any cutting or welding. - Just my $0.02. Good luck which ever way you decide to go with this. Don't forget to post pictures!

PS - For the most part I don't know specifically who my great grandfather worked for during the late 1890's - early 1910's. He was in Chicago for most of the period but he married my great grandmother in Elkhart, Indiana. The only companies I know for sure that he worked for are the "Auto Parts Company" and the "Solid Axel Automobile Company", both in 1907 and both in Chicago. He was mentioned in a Wichita, Kansas newspaper in 1907 as being the representative for the "Solid Axel Automobile Company" visiting from Chicago to see about starting up a factory there. The family story is that he knew Henry Ford personally but I haven't been able to connect how they became acquainted. My great grandfather did patent the anti-rattle door latch that Ford used on his cars though, so maybe that is how they met? The family still has a box of his papers which includes sales catalogs for several early car companies from the region including: Star Automobile Co. (Chicago), C.P. Kimball & Co. (Chicago), Oldsmobile (Lansing, Michigan), Jewell (Massillon, Ohio), Duer (Chicago) and the Couple-Gear Freight Wheel Co. (Gran Rapids, Michigan). We don't know if he worked for any of these companies - maybe he was just shopping for a car!

MarkV
 

fishguts

New Member
Sep 7, 2010
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southeastern MA
You sure know a lot more about your family than I do mine. And it sounds like there is more to uncover. I really enjoy reading about people who were there at the birth of the motorized vehicle - car/truck/motorcycle/boat/airplane age. It was an incredibly creative time. Somewhere I have a photo of my grandfather riding a motorcycle during WWI. He was also a pilot.

Here's a photo of the frame I have - 1940's Roadmaster. I have a welder so adding tubes is no big deal. I do like the Worksman bikes and that might be the better way to go since they are so heavy duty. I've priced them with a front hub brake which I think is essential. I've gone this direction for now because of that lower tube, but you're right - I could transfer the tube to a Worksman. Then again, I have a buddy with a tubing bender ...