I'm planning to adapt a factory Pre-Unit rigid rear section to the Duplex front loop on my '61 T110. Ideally I would have just started with an early 50's but sometimes you can't be that picky when the right project opportunity comes along. I'm told a
ftermarket Unit hardtails (like the
David Birds,
FMW,
Elswick's, etc.) bolt right up to a Duplex frame but I really want this one to look like a stock early 50's bike. The factory rigid rears are starting to get a little scarce, especially those that haven't been butchered almost beyond use. I feel a little better that I was able to find one that has already been cut, probably with the intention of doing exactly what I am hoping to do.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgtic8HFfCoHGi68ZW4lI2YVXCk3bDnApH1OorH7o5HWHQqR4i49ez0egLKK1UynkiLjVmfecS353T-Kah7HBMtqn_Nyr7T7rW0bIs04fs7JZSXyzKLAZ_QpJBOM7B5S9dQMy5x-WQaAUg/s400/Rear.jpg)
Here is a side-by-side photo with my friend's Pre-Unit rear section that has stock lower tubes.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiIpbqrIX2TK7LNayY9nkNmTlIRiCKOyGKiO03itjg0MaCahjmhhcLYoXpc5MdEFOKdeqTkjeMRI-edOMqtH3ofBWLGeVbLguCSGwAfU7AyjXSiMoUm9hQpZqjlCPw29mijQfS9I7aARiM/s400/Rears.jpg)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg6lpXOCm-KbtODfDRSfkhA0IBuN12EL28rcH2KRSRUmusQ7ypieZ4eYoqW1CUCOmg8M7VSSf6h6r5icSXOB0Dt7DHCwRVCmXN8MDO6Qrm7vTu8uOOuXJxB1IDZq-i9Q22KtsFPUKWS3nE/s400/Rears2.jpg)
I'm not the first to do this (no one is ever the first to do something with bikes this age). The following it a Duplex Pre-Unit that has had an early rigid rear modified to fit.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhD3gRnq-QpKb3g25LX2MB7Yt78w-wjnSLq1N30SLIpzKESrzYpP0amo_wc-aYGIflLs5nmOSAZ3jNG9clqQrKe7GN7ZifFmuPryKR3R3j-gfJ_WM-0_cB0Mai-4Xs5NkBv2FCRlnJBvkc/s400/T110Bobber.JPG)
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhKInNfHsCk99GIr4kKFNt_66L9BaqEwslYrpPFoFrbW37KyiJ7CDw4SxyUK1X7akjJbZIsq1KrgZdf7K69BY1sJDB5uVqqi1RJuZdOzs3gha52BH1XcXAm1sfn23n4idw8olncbJm4VMg/s400/T110Bobber2.JPG)
The spacing where the rear section bolts to the frame is wider on the Pre-Unit than the Duplex/Unit mount. I'm thinking I could just machine two 11/16" spacers to compensate. Obviously the lower mounts are going to be a little more involved. I'm hoping not to have to tear the whole bike down to the frame to mock it up. I'm thinking I might be able to use a Unit front loop for mockup.