crowned fork replaces the original plans for a unicrown
The front fork was planned as a custom unicrown affair. Very tough to miter and get right. As we studied the diagram for it, we realized fitting in room for a fender would be very, very tight indeed. As we thought about alternatives, it occured to simply use a crown fork lug. It would give us plenty more space, be far far simpler to construct, and probably come out much closer to spec.
When I considered that there were no meaningful advantages to the unicrown design, I tossed it out, and replaced it with the simpler crowned affair.
The only weird part will be actually bending the fork rake into it. That’s just done with physical brutality. Sulaiman assures me it’s not too terrible a job, and next to impossible to overbend the rake. Last time they had to recruit a 200lb man to lean into ti. Anyway, the fork goes in the bottom drawer until after I finish the rear triangle.
Now the rear triangle is the tricky part. I’m building monostay unicrown stays. Essentially they’re also unicron bicycle forks in service as chain- and seat-stays. The monostays will be split into two using S&S Couplers. This is what makes the bike massively deconstructible. The better part of the day was measuring, squaring, and rechecking the design to ensure everything fits.
unicrown monostay system with S&S couplers
I included two special considerations, this being a touring bike: 1) enough wheel clearance that I can install a fender onto the monostay 2) worst case scenario, I destroy my tires entirely and need to replace them with the crudest, chunkiest shitty BMX tired I can buy off someone. This bike is meant to be a survivor, a JACKAL, not a highly-strung, finicky athlete that needs a precise diet and care. This lengthens the wheelbase of the bike beyond original plans, but that only makes for a more comfortable ride. My headtube angle came in too sharp (69° instead of 70°, so I would like to prevent this to becoming an itchy, irritable criterium racer bike anyway)
It took me the better part of an entire afternoon to clean up the drawing and then map out the stay system. Tomorrow I will commence building the chain-stay. Should be fun: unique bespoke engineering.
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