Tuesday, June 25, 2013

Duplex T110 Factory Rigid

A recent conversation I had with Flathead Rob got me think about modifying a factory rigid rear section to fit my '61 T110.  The following is a photo of a Duplex with an earlier rigid attached.
Studying the photo above got me questioning if the seat-to-dropout tube is stretched.  These are stock.

Are they the same or not? Anyone know of a clever way to derive approximate scale  dimensions from a photo?

It's also got me thinking about jigs. Obviously the length of the one below is not stock but I like how the engine plate mounting holes were used to tie the frame to the jig. Crime Scene Choppers has a pretty nice blueprint for a frame jig available on there website. I'm concerned the material required to build a jig might not be all that much cheaper than paying someone that knows what they are doing handle it.

The cop out option would be to buy a Unit hardtail from Acme choppers. I like the stock looking axle plates. They claim to build custom hardtails too.


Flathead45 said...

A good way to get dimensions is to use the cursor position in a photo editor to get X and Y pixel coordinates. Then calculate a multiplier by comparing distance in pixels to a know distance on your bike that you can measure. Hope this makes sense. I could show you.

Flathead45 said...

Something is definitely not stock. Note the 3-4" empty space behind the transmission. Not there on the stock bikes.

BitMonkey said...

Good eye.

The seat tube on a true rigid front frame loop runs between the engine and transmission. When the swingarm bikes came along it was moved behind the transmission. It could then be used as an anchor point for the swingarm pivot.