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Shaft-driven bicycle. Here with a bevel gear:
https://s3-us-west-1.amazonaws.com/h...en_bicycle.jpg
30-second video of one in action:
https://www.youtube.com/watch?v=6Jefi1cwpeI&app=desktop
More: https://en.wikipedia.org/wiki/Shaft-driven_bicycle
Previously:
https://www.homemadetools.net/forum/...8421#post87491
https://www.homemadetools.net/forum/...646#post104908
The first pic looks to have been a bike made in the late 1800's I remember seeing one in a Transportation museum somewhere I think it had a clickity-clackity sprag clutch for a coaster doubt if they were immensely popular probably too expensive to manufacture given the technology of the time.
Neat, I agree with Frank S, the first one looks like one of the bicycle mechanisms in my Hiscox "Mechanical Devices and Movements" books.
No sprocket to catch my pant leg in. And a few less moving parts than a chain, I think. Looks like a right design to me.
I have a friend who has one of these, only his has wood rims, and I seem to remember the gears were more enclosed.
Steve
Tank tread bike.
https://s3-us-west-1.amazonaws.com/h...ad_bicycle.jpg
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Well he can go from a high boy to a chopper on the roll but can he return to hi boy without stopping. Maybe all he would have to do would be to grab the front brake and lean forward.
This to me looks like one of those things that while cool to watch and probably to ride I can actually see one other aspect that would be useful.
Riding a bicycle with a fixed seat position gets tiresome at times so you stand up to relieve certain muscles.
This bike you could almost stand while sitting
One thing I did note though is the seat is still adjusted wrong for his legs
I wondered about this too. Found a different one doing this!Quote:
Originally Posted by Frank S
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Thanks Jon pretty much confirms what I thought, except the up and down could be a function of weight distribution on the gas shocks. Also the banana seat on this one allows for rider to stretch his legs as well.
Here's the first one of those I saw, includes a how-to: https://www.instructables.com/id/Tra...-Chopper-Bike/ I have a couple books of Atomic Zombie's bike deseigns, they range from useful to fun to just weird, to terrifying, like this one http://www.atomiczombie.com/ourhistory/Figure%207.jpg
Could always put 2 of those zombie bikes together to make a scaffold and use them to change the street lights otherwise nearly impossible to mount or dismount if you are not a circus performerQuote:
Originally Posted by bruce.desertrat
Must have been an attempt to add suspension to the bike to smooth out the rough ride over cobble stoneQuote:
Originally Posted by Jon
Thanks Jon! Interesting and fun use of hatch struts but think he needs hi-rise bars on it.
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А почему цепь? Чем кардан хуже? :пальцы вверх:
привод вала и передач, чтобы попытаться сделать механизм проще с меньшим количеством движущихся частейQuote:
Originally Posted by Slim-123
the drive shaft and gears is to try and make the mechanism simpler with fewer moving parts
they could also add another smaller gear to the pedal assembly to have a wider range of gearing but this would require a 2nd shifter just like the current 18 speed 2 derailer systems
If the pitch of driven side is equal, the 'pinion' could slide on a splined [square would do, or two flats on a round] axle, indexed for each ratio. A light spring could advance the position for speed, overcome by a lever to downshift.
Interesting what reduced friction vs chain is possible.
Notice one thing as well the teeth on the pinion are actually rollers just like in a chain further reducing the friction. the drive reminds me of an ancient pinion driven planter where the flat gear had a multitude of teeth in a dozen different ratios the pinion couldn't be just slid across the flat gear but had to be raised out of contact then lowered back in place but essentially it was the same concept think of an index wheel with bumps instead of holesQuote:
Originally Posted by Toolmaker51