Dual drive system
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Dual drive system
Hey fellas,
I've been searching the web for a system like this. Basically, I am looking to complete a bike with two chain rings at the crank and having dual freewheels on the back hub. Is this even possible? Please give any input you want, stupid idea, good idea, etc. Any info will help. I will post a drawing of what I am thinking of for all of you visual learners.
Thanks
I've been searching the web for a system like this. Basically, I am looking to complete a bike with two chain rings at the crank and having dual freewheels on the back hub. Is this even possible? Please give any input you want, stupid idea, good idea, etc. Any info will help. I will post a drawing of what I am thinking of for all of you visual learners.
Thanks
#3
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Theoretically I assume it would be possible if you used two of the same drive crank arms, and a symmetrical BB, and the same gearing on each side.
Sounds kinda neat actually. Serves no purpose, but eh.
Sounds kinda neat actually. Serves no purpose, but eh.
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I understand how it could work fixed but with freewheels wouldn't the freewheel on the left side just spin not doing anything?
#9
Your cog is slipping.
#11
Still kicking.
#13
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They do make left side drive freewheels: https://www.amazon.com/ACS-SouthPaw-L...uckduckgo-d-20
It's been done, in practice they would never both be engaged at the same time.
Examples: https://www.ridemonkey.com/forums/f85...a-unit-130683/
It's been done, in practice they would never both be engaged at the same time.
Examples: https://www.ridemonkey.com/forums/f85...a-unit-130683/
Last edited by wesmamyke; 09-07-12 at 09:10 PM.
#14
Still kicking.
I think it's the dumbest thing since the slapchop.
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If you looped one of the chains into a figure-eight, you could have a retro-direct. But that would disqualify you from the Single-speed forum...
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Haha wow I did not expect to have this many replies. Thanks for all the heads up, I was just looking at doing something different and a new project to play around with. I appreciate it fellas and I look to be talking with you guys more on here. Take it easy.
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What I see here are two track cogs on the rear wheel. If that's the case, then this setup can't possibly work well, because either one of the track cogs will be stripped, or at the very least be loosened from the hub, immediately. IOW, one of the drivetrains is just tagging along while the other one does all the.... driving.
A stupid way to add 1 Kg of unnecessary components to your bike, plus it will actually make the power transmission less efficient. And it becomes horribly inefficient if you don't maintain (clean, lube) the "inactive" chain.
EDIT: not sure what would happen if one used two freewheels, though. Maybe then it could work? Didn't think through that scenario.
EDIT2: I came to the conclusion, after some thinking, that this setup could work (correctly, i. e. with drive on both drivetrains) if one had cogs that aren't threaded onto the hub, but bolted or splined - and provided that the two cogs are exactly identical. And that the chainrings are symmetrical.
A stupid way to add 1 Kg of unnecessary components to your bike, plus it will actually make the power transmission less efficient. And it becomes horribly inefficient if you don't maintain (clean, lube) the "inactive" chain.
EDIT: not sure what would happen if one used two freewheels, though. Maybe then it could work? Didn't think through that scenario.
EDIT2: I came to the conclusion, after some thinking, that this setup could work (correctly, i. e. with drive on both drivetrains) if one had cogs that aren't threaded onto the hub, but bolted or splined - and provided that the two cogs are exactly identical. And that the chainrings are symmetrical.
Last edited by wroomwroomoops; 09-09-12 at 07:12 AM.
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If properly installed, it will work just fine. You shouldn't strip or loosen a cog. My thought is that since the cogs are threaded on, the will most likely be within a couple degrees of each other, so unless they and the hub are machined perfectly, one cog will be doing more propelling and one will be doing more braking.
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I'm glad we agree on the main points.
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Hey fellas,
I've been searching the web for a system like this. Basically, I am looking to complete a bike with two chain rings at the crank and having dual freewheels on the back hub. Is this even possible? Please give any input you want, stupid idea, good idea, etc. Any info will help. I will post a drawing of what I am thinking of for all of you visual learners.
Thanks
I've been searching the web for a system like this. Basically, I am looking to complete a bike with two chain rings at the crank and having dual freewheels on the back hub. Is this even possible? Please give any input you want, stupid idea, good idea, etc. Any info will help. I will post a drawing of what I am thinking of for all of you visual learners.
Thanks