I wrote this several days ago with my intentions fresh in my mind and a belly full of jet fuel strength Starbucks coffee, so excuse me if its a little frenzied seeming.
"So as I write this I am still waiting for 'approval of a moderator' of my introduction post, so I can get this posted as these questions having been burning in my mind now for a week.
So I recently had a POS 12 speed mountain bike that was actually a 6speed due to the crank sprocket derailer being smashed, so I got the wild notion of mounting a rototiller motor (or a converted vertical shaft motor as seen - here Youtube embedding did not work for some reason, so I have edited it to a hyperlink) so after I found that its possible to use whatever motor I happen to come across (vertical, as well as horizontal) I got to work thinking up a drive system to utilize the stock 6 gears on the rear wheel.
Though the bike was stolen from me April 21st due to my stupidity not forking over some cash for a chain and lock, I will need to get another bike but thats no problem - craigslist FTW
I see a nice Predator for $100 thats an estimated $130-$160 motor bike minus the price of my intended drive train fabrication.
The nitty gritty!
So If I have a counterclockwise motor rotation from lefthand side view of the theoretical bike with the motor mounted to the frame what I'd like to have is a Vbelt pully (2 1/2"? 3"???) like what you'd see on the alternator of a 50's - 80's american made road car (maybe a double like this, the other to run to an alternator for power generation; lights, radio w/ battery {would balance out the motor's weight on the right hand side of the bike too})
Then to the seat post portion of the frame, another of the same pulleys somehow set up as a tensioner, like on a serpentine belt system (swing arm style) with a lever attached, maybe ratcheted, maybe spring loaded - I dunno yet - I suppose either way its just the swing action that is important. then - and here's big question (1) of 2, will a typical V belt pulley from a power steering pump be like a gear reduction? In my mind I see this being a 6" - 10" pulley being mounted straight to the left hand side of the pedal crank - see where I'm going with this? rotational force from motor, naturalized with lever in "neutral" position, lever pushed/pulled, compensate resistance on motor with "hitting the gas" - just like with a car/truck/motorcycle - simple clutch, right??!?! yes, yes I know I will go through belts, but I'm sure I can find a sweet spot with off the line acceleration and belt conservation engagement tactics over a time.
And yes if your thinking I aim to eliminate the pedals all together, yes I am - to **** with pedaling, why would I put a motor on a bike only to have pedals to complicate design and have to find ways to make them usable/usefull - or just vestigical and a danger to my legs and feet, and if this brings up questions of law and "looking legit" I don't care, I am revoked till 2021 and am a habitual offender, but I intend to decal the motor as "49cc" and will deny larger size or capable speeds greater than 25mph till I'm blue in the face.
Moving along . . .
Now with proper chain oiling and "letting off the gas" during gear change both up and down (i.e., 1st to 2nd . . . 6th to 4th and everywhere in between) can I expect to (and this is coupled with the Question of gear reduction at the Vbelt pully array) have a shot in **** of preserving the chain and derailer +/- wheel and derailer bearings?!?!??!?!
Will this work? Or will I just creep forward and choke on a fast growing cloud of rubber smoke? Will I shatter bearings and collapse derailers? will I even have a half a chance in **** in this being something feasible??!?
I am on a budget, I currently make less than $10 p/h and work an average of 23 hours a week, I am however very mechanically inclined and resourceful ( my dad works at Cunningham MFGco - a hydraulic cylinder machine shop with CNC's, Lathes, drill presses and all other manner of heavy machinery for producing of mechanical things within microns - but I plan on using only nuts and bolts from the hardware store, salvaged car engine parts, a miliwalkie corded drill and some angle iron/steel (for things like frame reinforcement and extra motor mounting brackets.
I imagine that a human can exert a force on a bike crank of somewhere around 100 foot lbs of torque putting the drive parts at a rating slightly higher than that, I know that with proper gear reduction ratio my idea WILL work - but it would be saddening if the motor still put so much torque on the bikes drive train as to destroy it and endanger my nether regions ::75:
Also any Ideas on how to make all this work out on a 2 piece rear suspension frame?"
So thats what I wrote up the other day, now I HAVE searched alot and have found alot of info about my plans though I am posting this anyways because the info I did find was spread far across this forums various boards - this way "the whole picture" is under one header and it will give me a good idea as to how well this may or may not work out with some comprehensive replies and or criticism.
Thanks ya'll.
-Diagaro
"So as I write this I am still waiting for 'approval of a moderator' of my introduction post, so I can get this posted as these questions having been burning in my mind now for a week.
So I recently had a POS 12 speed mountain bike that was actually a 6speed due to the crank sprocket derailer being smashed, so I got the wild notion of mounting a rototiller motor (or a converted vertical shaft motor as seen - here Youtube embedding did not work for some reason, so I have edited it to a hyperlink) so after I found that its possible to use whatever motor I happen to come across (vertical, as well as horizontal) I got to work thinking up a drive system to utilize the stock 6 gears on the rear wheel.
Though the bike was stolen from me April 21st due to my stupidity not forking over some cash for a chain and lock, I will need to get another bike but thats no problem - craigslist FTW
I see a nice Predator for $100 thats an estimated $130-$160 motor bike minus the price of my intended drive train fabrication.
The nitty gritty!
So If I have a counterclockwise motor rotation from lefthand side view of the theoretical bike with the motor mounted to the frame what I'd like to have is a Vbelt pully (2 1/2"? 3"???) like what you'd see on the alternator of a 50's - 80's american made road car (maybe a double like this, the other to run to an alternator for power generation; lights, radio w/ battery {would balance out the motor's weight on the right hand side of the bike too})
Then to the seat post portion of the frame, another of the same pulleys somehow set up as a tensioner, like on a serpentine belt system (swing arm style) with a lever attached, maybe ratcheted, maybe spring loaded - I dunno yet - I suppose either way its just the swing action that is important. then - and here's big question (1) of 2, will a typical V belt pulley from a power steering pump be like a gear reduction? In my mind I see this being a 6" - 10" pulley being mounted straight to the left hand side of the pedal crank - see where I'm going with this? rotational force from motor, naturalized with lever in "neutral" position, lever pushed/pulled, compensate resistance on motor with "hitting the gas" - just like with a car/truck/motorcycle - simple clutch, right??!?! yes, yes I know I will go through belts, but I'm sure I can find a sweet spot with off the line acceleration and belt conservation engagement tactics over a time.
And yes if your thinking I aim to eliminate the pedals all together, yes I am - to **** with pedaling, why would I put a motor on a bike only to have pedals to complicate design and have to find ways to make them usable/usefull - or just vestigical and a danger to my legs and feet, and if this brings up questions of law and "looking legit" I don't care, I am revoked till 2021 and am a habitual offender, but I intend to decal the motor as "49cc" and will deny larger size or capable speeds greater than 25mph till I'm blue in the face.
Moving along . . .
Now with proper chain oiling and "letting off the gas" during gear change both up and down (i.e., 1st to 2nd . . . 6th to 4th and everywhere in between) can I expect to (and this is coupled with the Question of gear reduction at the Vbelt pully array) have a shot in **** of preserving the chain and derailer +/- wheel and derailer bearings?!?!??!?!
Will this work? Or will I just creep forward and choke on a fast growing cloud of rubber smoke? Will I shatter bearings and collapse derailers? will I even have a half a chance in **** in this being something feasible??!?
I am on a budget, I currently make less than $10 p/h and work an average of 23 hours a week, I am however very mechanically inclined and resourceful ( my dad works at Cunningham MFGco - a hydraulic cylinder machine shop with CNC's, Lathes, drill presses and all other manner of heavy machinery for producing of mechanical things within microns - but I plan on using only nuts and bolts from the hardware store, salvaged car engine parts, a miliwalkie corded drill and some angle iron/steel (for things like frame reinforcement and extra motor mounting brackets.
I imagine that a human can exert a force on a bike crank of somewhere around 100 foot lbs of torque putting the drive parts at a rating slightly higher than that, I know that with proper gear reduction ratio my idea WILL work - but it would be saddening if the motor still put so much torque on the bikes drive train as to destroy it and endanger my nether regions ::75:
Also any Ideas on how to make all this work out on a 2 piece rear suspension frame?"
So thats what I wrote up the other day, now I HAVE searched alot and have found alot of info about my plans though I am posting this anyways because the info I did find was spread far across this forums various boards - this way "the whole picture" is under one header and it will give me a good idea as to how well this may or may not work out with some comprehensive replies and or criticism.
Thanks ya'll.
-Diagaro
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