Thanks for the feedback!
Originally Posted by
Andrew R Stewart
"Death trap" is what is said after the worst happens but you're not there yet
My first concern is about a drop out extender thingy not being contained well enough to be stable/safe over the miles. I remember cutting off fork blades as a kid to extend another bike's forks with... For a short term trial when you are focused enough to check the hardware and fittings before each ride I see little issue But people tend to forget and think the "current state of affairs" will continue even if they stop paying attention (hence many "JRA" claims). If you do find the extender idea works I strongly suggest brazing/welding on the long term thingy.
Originally Posted by
zandoval
I would just make a long dropout out of appropriate material rather then use a two component device. I would then saw off the old drop off and braze in the new one...
The more I think about it, the more it seems like the right move would be to just make it permanent from the get-go. New dropout would be an easy time to add eyelets and stuff. From a style perspective I'd probably go with something like option B and attempt to de-rake the fork a bit if I didn't like the handling. If I'm making bolt-ons _and_ a drop bolt or something just to test it, I'd rather spend that money and effort just putting in longer dropouts and better brake mounts
Originally Posted by
Andrew R Stewart
However given all the mucking about mentioned as well as what the different rim brake track radius brings I suggest that you consider a bike with the wheels size you want already speced. Sadly most all the low cost folders are made of fairly heavy tubing and have components that are also both weighty and often lacking sporting qualities. I do have an Automoto 406 rim folder with a Sachs 3spd that could easily leave my garage for not too much $. Andy
I'm probably not ready to buy anything just yet but let's see a pic!
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While we're on the topic of foolish and excessive things to do with a miniature bike fork, I had a couple other harebrained ideas:
- What about adding a disc brake mount? I understand that generally the opinion is "don't add a disc mount to a fork that wasn't designed for it" but it seems to me the force on the disc would be a lot smaller because of the small wheel, so maybe not a disaster? If I'm already designing and making new dropouts it seems like a disc tab is not too much extra trouble and maybe could be integrated into the dropout.
- Since really the goal here is to increase axle-to-crown, what about just brazing on another crown race seat right on top of the existing crown race seat (assuming I can find someone locally with a crown race cutter)? The kingpin, like the R20 and a lot of other folders has an extra long steer tube to accommodate the (unnecessary to me) quick-release stem clamp. Presumably one could shift some of that extra steer tube length below and still have plenty left over for the headset. Would having an extra 15-25 mm (I'm guessing, based on the apparent stack height of those clamps) of steer tube between the fork crown and the race be a structural liability? Might depend on how long the butted section of the steer tube is (if there is a butted section?)