We have started a Kyoto Cruiser. There are some parts sourcing 'challenges' that we have here:
- No imperial sized tubes. The nearest size I could get for the chassis (without major hassle) was 40mm square with 1.5mm wall. I wanted a 1.8mm wall, but I will have to make do. Perhaps some strategic gussets will provide strength. I plan to make a scale model from drinking straws and then load it to see where it bends / breaks - cheaper and quicker than finite element analysis...
- Similar issue with the rear axle, it won't be 3/4 inch, but rather 20mm, actually a little beefier.
- Bike parts are not cheap here. So eBay is my friend - Avid BB7 brakes are coming from Hong Kong, wheels and other drivetrain from UK and I have more sourcing to do yet...
- MIG shield gas is expensive for home use. Need to take a yearly contract on bottles and then start to pay for fills. I have a true Heath Robinson affair set up with an inverted CO2 fire extinguisher with the nozzle unscrewed and the regulator screwed in its place. Works like a charm (although argon would be nicer...)
- People don't throw things out here like I saw in UK. So you have to do a deal of 'social engineering' to get people to part with that rusty heap they have in their storeroom.
- In theory, my little mini-lathe only does metric threads - but I believe I can get so close to 24TPI as makes little difference. There's a great little program called 'gears' by Paul Bussieres (just Google it) that shows that I should be able to get within 0.06% of 24TPI, or about 10 microns over the length of the freewheel thread, probably close enough! The other challenge will be turning the relatively large lump of metal (I got some 65mm bar yesterday) with the little machine. I went for aluminum alloy - I'm confident that it will hold up bearing in mind 'factory' bike bits are a lot less beefy and are also made from aluminum alloy. If all fails, I have tame local help from the nearby fix-everything metal workshop (from tractors to huge (90 tonne!) earth moving machinery) (plan B). Also looking at plan C which is the welded flange to bottom bracket cup.