# Iver Johnson info on year/date codes?  Any takers......



## basementchoppers (Dec 25, 2010)

I found a couple of Iver Johnson frames.  I am trying to figure out what year they were so I can start collecting parts for a build (or two).  Anyway, any help identifying the years and info for parts.... or parts you want to sell! would be helpful.

date codes on frames...
555491
572519

same type of frame but one has a smaller opening where the back of the tank would fit into the frame.


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## 66TigerCat (Dec 26, 2010)

Mid-30's I'm guessing.

Jim


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## bud poe (Dec 26, 2010)

Pic's would help...


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## basementchoppers (Dec 29, 2010)

pics!!!!


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## slick (Dec 29, 2010)

If you would like to sell either frame please let me know. I love Iver Johnson stuff.


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## basementchoppers (Dec 29, 2010)

I'd give you a frame and $ for a tank for one of 'em......


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## slick (Dec 29, 2010)

I wish I had one. That is VERY rare to come by. I do like the 2nd frame pictured though. The 1st frame would be easier to find a tank for but that 2nd would be impossible. I have an earlier truss frame Iver i'm in the process of piecing back together right now but i do love that 2nd frame you have pictured! Very great finds indeed.


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## basementchoppers (Dec 29, 2010)

I looked through your pics and am impressed with your collection.  You must have a very understanding wife.... LOL If you could point me in the right direction for information for my frames, so I could do more research that would be most helpful.  P.S. I picked up Iver fenders, forks, a sprocket and a seat-post today!  Don't ask me what I paid...  I might be ashamed to say.


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## basementchoppers (Jan 10, 2011)

Still looking for info on the frames.   Any help would be much appreciated!!!


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## DonChristie (Jan 10, 2011)

The first frame is mid 30s...here is one on eghey...http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120668873996&ssPageName=STRK:MEWAX:IT

The second one is newer, 1937 Streamline, I think...http://cgi.ebay.com/small-1937-IVER...350?pt=LH_DefaultDomain_0&hash=item5636650c16


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## basementchoppers (Jan 11, 2011)

thanks, I guess its best to start collecting old Iver adds and such to help with part identification as well.....
Heck nothing that's worth doing is easy.


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## DonChristie (Jan 11, 2011)

Unfortunately there is no serial number chart for IJs. They started manufacturing bicycles in 1899 and ended @ WWII or so. You gonna build them up?


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## RMS37 (Jan 11, 2011)

There have been a number of posts regarding Iver Johnson on this site over time. I have begun recording serial numbers as they come available and although I have only recorded a handful to date a few early observations may be useful.

It appears that the serial numbers are consecutive, perhaps from the earliest bikes through the end of production at the start of WW2. 

The highest number I have recorded is 604615, which is an adult lightweight model with balckout fitments that probably correspond to a late 1941/early 1942 build date.

Recently an early camelback balloon Iver was advertised that had metal clad wood balloon rims. This bike also generally appeared to be original and was purported to have been originally purchased in 1935. Metal clad/wood core balloon rims were mainly used in 1934-35 and were outmoded by the end of 1935. Traditionalists that Iver Johnson were, they may have used these rims a bit later than others but still this bike yields a reasonable serial number for an early Balloon Iver. That serial number is 540081.

Just using the above information (and assumptions) provides a picture of Iver production during the balloon years (1934-1941+) consisting of no more than about 60,000 or 70,000 units. For comparison sake, Schwinn built about 1,500,000 units over the same period of time; a ratio of less than one to twenty.

Going a step further, if annual production was linear then annual production would be less than 10,000 units and serial number break points could be estimated for the end of each year. It is unlikely though that Iver production was linear throughout the period and it is also difficult to predict the exact curve production followed to extrapolate the annual production.

Still I believe the above model is a start. The most useful thing to do is to add data points to the model especially for Balloon frames with lower serial numbers or bikes with higher serial numbers that would expand production further past 600,000.

Based on this start, and my own slightly weighted model I have begun building, I would predict that the Moto-balloon frame you have is likely from about mid 1936 and the Streamline frame is from mid/late 1937.

Iver tanks were mentioned earlier in this thread; to the best of my knowledge, Iver produced two boy’s balloon tanks, the hexagonal tank for frames like your Moto-balloon, and a hanging straight-bar tank for a frame that was produced only near the end of Iver production. Iver never made a tank for the Steamline frames.


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## slick (Jan 11, 2011)

I have what I believe is an Iver truss frame. The headhadge screw holes appear to be in the typical Iver triangular positions? I'll post some pictures in a little bit. I'll try and locate the serial numbers also.


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## DonChristie (Jan 13, 2011)

Hey Phil and company-I checked my serial number for my believed to be 1930-1935 IJ Mobicycle Motobike. The number is 535858. Here are pics for reference. I would love to see your IJ serial number list you have so far.
Thanks, Don


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## basementchoppers (Jan 16, 2011)

RMS37 -Thank you very much for the information!  I understand that Iver Johnson could have made more bikes at different times, but what you have done is a great example of extrapolating a reference for frame numbers as they correspond to years.  Both frames I have will be built back up, albeit as close to correct as I can get.  Thanks for letting me know that the streamliner never had a tank, I would hate to have spent all my life looking for something that doesn't exist!  I will keep looking through old book shops and bicycle stores for information and pictures, and when I find enough I will post it and hopefully help others as you have done for me.  Sometimes finding out information about these old bikes is as fun as restoring and riding them!


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