Iver Johnson (Atypical) rat bike build

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I decided to do a build incorporating some very unusual parts

First off is a prewar Iver johnson frame I acquired in a trade
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Most of these bikes seem to have a schwinn like following for guys who restore bikes
but I have not seen many if really any done up as a full on rat
they posses a lot of proprietary size parts that I think make it difficult to customize these


One problem the have is their different size B.B
too small for standard one piece cranks
too big and not threaded for the euro B.B
Turns out to measure out to 43mm which is the same size as the Roadmaster Jr one piece cranks (as well as newer children's bikes)
26495534507_0a5dd8583c_b.jpg

The cup on the far left is the stock Iver version
It normally is used with an Iver 2 piece crank so the center whole is a lot smaller

I got lucky and found a one piece crank from a children's bike that is longer than normal (for a child's bike)
This one measures 140
Standard full size crank measuring 165 or 175
standard kids bike crank 115 or 125

There is a possibility of using bmx 3 piece cranks but the mid B.B size uses 41mm bearings
so those are a hair too small
the other is to use the spanish B.B size bearing that are 37mm but I need an adapter fabricated
or find an aftermarket sealed bearing that is 43mm outside with a center hole of 19mm or 22mm

even though the current one piece crank I found is thinner than a typical one piece
I still had trouble putting it in the B.B with both new cups in the frame
so I installed the chainring side cup first
then install the crank
after getting the crank through then I can set the last cup in before putting on the bearing and hardware for that side
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for wheels and tires
I had an old wide schwinn s7 back wheel that had been collecting dust
then threw on the 26 x 2 x 1 1/2 (54-571) tandem tire to give it the widest possible look (for a s7 that is)
26495532977_32b4d6db6c_b.jpg


the wheel on the right is supposedly from another tandem
it is technically an old 650b size rim which is the same as modern 27.5 rims
The tire that will be going on that is a 26 x 1 1/2 (40-584)


the fork isnt anything special just something mid century roughly
came from my parts pile but it fit the iver frame
41323863192_5a32ec5f5e_b.jpg

the handlebars and dog bone goose neck are from my 2017 build off bike B/MSR#305

http://www.ratrodbikes.com/forum/index.php?threads/b-msr-305-finished-at-last-minuet-that-is.103870/

they are the wald mini ape bars that i found can be ridden in regular position or turned upside-down and used like road bike bars
the dog bone goose neck (along with the stem riser) allow for a quick change in the bars orientation
 
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At the local co-op I found two possible chainrings to use
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I liked the quick gear exchange concept that I also had done on B/MSR#305 that I decided to incorporate it into this build

the top left is called a three arrows (44tooth) and is popular with vintage bmx
next it is the larger attaching ring (52tooth)
or my other option
the large (52tooth) chainring on the lower right is from a schwinn 2 piece chainring
but normaly is attached to a 39tooth sprocket
for the quick gear exchange to work i needed something in the 44 to 48tooth
and I found this huffy? (44tooth) ring that fits the holes from the large schwinn

In between the chainrings are newer head tube cups that fit very close to the original iver cups
so i may be using those as well
 
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Got the bendix internals put in the s7
and installed the bottom bracket parts
so hear are a couple of mockup views
may not look super unique to the casual observer
but to those who know
bet it is weird seeing the fattest tire able to me mounted on an s7 rim
along with a standard looking crank/sprocket in an iver johnson frame

26593986287_58489b88a9_b.jpg


39656908670_bfdcb3b60e_b.jpg


This bike (considering it is all steel) is actually fairly light
a true hot rod in my opinion
 
Had a little issue finding a particular bolt for the chainrings on this build
but ended up finding a something similar that will work
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the bolt in the center is called an axle bolt
I had found 2 but not 3 of them and most the stores that sold bolts only had them in larger sizes
But at an Ace hardware I found these other bolts (the 3 pictured) that work just as well

Socket shoulder screws (left side)
axle bolt (on right)
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I also thought it would be neat to show the size difference of the hardware from a standard size one piece crank
and the smaller kids one piece crank
to show the amount of weight savings in the rotating weight
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threw on the bars in race mode
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one of the things about using the 3 arrows chainring that i noticed recently
it matches the iver headbadge which has 3 screws attaching it and is somewhat in the shape of an arowhead

iver-johnson-bicycle-head-badge_1_4ee2d37221b1bf1880c2ca899531f9cf.jpg



the other thing that i re-did was eliminate the quick exchange rear sprocket
while that set up was meant for a racing themed bike
with the smaller front sprocket i can get away with a chain with multiple quick links
42154889821_b6cd06cb62_b.jpg

take both off and put one back and it eliminates about 2 or 3 fill links enough to fit on the smaller front sprocket without removing anything else
true i could buy a two speed rear coaster but i am trying to use parts that are not that desirable
so im want to to avoid costly options like a two speed
 

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