Eliminating the driven sprocket
- Thread starter Pablo
- Start date
well first off you cant use your derailleur with a setup like that. Dimension Edge and Staton have both done what you are trien to get done. I am the son of the owner of Dimension EDGE and know first hand how dangerous running an engine through your derailleur can be. I dont have the time to explain how it all happens but your derailluer will end up in your spokes if you keep it the way it is... our fix for that situation is just using an internal shifting hub.
Sorry i couldnt go into more depth but i posted this at work so gotta go.
Sorry i couldnt go into more depth but i posted this at work so gotta go.
I would love to hear more. I admit I don't have a lot of miles on mine yet but if my physics is correct there is a lot more force exerted by a 200lb body at full force against the cranks than a little motor can generate. The motor has the advantage in RPM not torque.
Sorta what I was getting at......if you have some super low gearing spinning at 20,000 rpm....I could see the dérailleur launching lunch.
That is so cool Pablo ! Can you still have the pull start put on the engine ? How is it at hill climbing and speed ? Do you use the clutch for anything ? What is your anticipated availability date and cost ?
I'm sorry for all the questions but that is soooo cool. It's the same principal as the Cyclone Electric Bike Kit Electric Bicycle Motor Kits from Cyclone-USA .
I'm sorry for all the questions but that is soooo cool. It's the same principal as the Cyclone Electric Bike Kit Electric Bicycle Motor Kits from Cyclone-USA .
Your quote "29t rear sprocket to a 58t and everything in between"
Save one for me please!
How much. Will you sell pieces.
For example crankshaft sprocket now. Jackshaft,brackets,and chain later.
I was going to try a rack mount, BUT I will wait for this!!!!
Save one for me please!
How much. Will you sell pieces.
For example crankshaft sprocket now. Jackshaft,brackets,and chain later.
I was going to try a rack mount, BUT I will wait for this!!!!
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Before i get into this i am not trien to argue with you on this subject. just letting you know what problems we had.
its not about the torque applied, its the pulses of torque applied that launches your derailluer. not to mention the torque you are producing at the wheel from the engine is much higher then you might think. you have alot of gear reduction going in in your set up. the gear reduction in the diferential used 7:1 reduction (i could very easily be wrong on this).
The derailluer worked fine for many monthes(this bike was my rider at the time). but one fateful day at the sturgis bike rally, i was climbing the last hill into deadwood from sturgis when suddenly my rear wheel locked up. i somehow kept the bike from going over and when i stopped i noticed about 1/4 of my 12 gauge spokes snapped, and what was left of the derailluer was intangled in the remaining spokes.
We took that same bike, got it a new rim with a nexus 8 spd internal hub and the thing still runs today. i am just trien to let ya know that expecting your derailuer to handle all of that is just asking for trouble.
its not about the torque applied, its the pulses of torque applied that launches your derailluer. not to mention the torque you are producing at the wheel from the engine is much higher then you might think. you have alot of gear reduction going in in your set up. the gear reduction in the diferential used 7:1 reduction (i could very easily be wrong on this).
The derailluer worked fine for many monthes(this bike was my rider at the time). but one fateful day at the sturgis bike rally, i was climbing the last hill into deadwood from sturgis when suddenly my rear wheel locked up. i somehow kept the bike from going over and when i stopped i noticed about 1/4 of my 12 gauge spokes snapped, and what was left of the derailluer was intangled in the remaining spokes.
We took that same bike, got it a new rim with a nexus 8 spd internal hub and the thing still runs today. i am just trien to let ya know that expecting your derailuer to handle all of that is just asking for trouble.
Mirk,
I appreciate the insight. I don't claim to know everything and again don't have a lot of miles on my prototype yet. It is definitely something I will keep an eye on. If you don't mind me asking what exactly failed? Did the hub break? Did the freewheel mechanism fail?
From a business standpoint, I think that this decision should be up to the customer. Whether they use a standard derailleur, an internal or a NuVinci will be up to them. At least this gives them the option of both gears and type of rear hub they use.
I appreciate the insight. I don't claim to know everything and again don't have a lot of miles on my prototype yet. It is definitely something I will keep an eye on. If you don't mind me asking what exactly failed? Did the hub break? Did the freewheel mechanism fail?
From a business standpoint, I think that this decision should be up to the customer. Whether they use a standard derailleur, an internal or a NuVinci will be up to them. At least this gives them the option of both gears and type of rear hub they use.
derailer in the spokes on standard bicycle is usually caused when chain gets caught up and pressure on peddals pulls derailer into wheel. would usually be in top gear, closest to spokes. a cause of failure with motorized set up as i could see is such high revolutions of chain could make it hard for jocky wheels in derailer to keep up, any drag or friction would again pull derailer to its doom in a mess of broken spokes. maybe if this high revolution aspect was avoided by adjusting riding style, ie avoiding reving the guts out in low gears, problems may be avoided? shimano make a cheeper rear derailer with extra large jocky wheels this could help?
Well here is the schwinn with the freewheel front crank. Just slapped it together to look it over. Looks like it would be a good choice for the jackshaft conversion...boy if I just had the layout for those side plates..lol Oh well Ghost0 I have to build it have like you and other wanted to do this but I never know of the cranks so now I have the missing link. When I get a chance I'll pull the crank or if you want anything measurement etc etc just let me know. As soon as I pull the crank and see if it will fit any of my other bikes then I'll have to go get the other 4 cranks.
Attachments
This looks like it could work with a standard jackshaft. It has two chainrings, one for the motor and one for pedals.
Schwinn FFS Front Freewheel Chainrings Set NOS Shimano - eBay (item 360019097754 end time Mar-30-08 21:33:47 PDT)
Schwinn FFS Front Freewheel Chainrings Set NOS Shimano - eBay (item 360019097754 end time Mar-30-08 21:33:47 PDT)
You beat me to it. I was wondering how to freewheel the sprocket. There is some controversy as to whether the derailleur can handle the load, if the rear freewheel fails it would not be fun. I think they make a heavy duty rear cluster. I think you need to check the gear ratio, triple reduction, it just looks like it will have a low gear all around, I could be wrong. I would like to see a small two speed, I was thinking of using some gears from a small Honda the only thing is gears will make the engine have to reverse rotation, a two speed would be easy. A two stroke will run in both directions, years ago my Bultaco at a signal acted funny and when I went to go it only had 4 gears in reverse, it hiccuped and was running backwards. Have fun, Dave
It may be yours but without a patent, anyone can copy and market it. I hope you beat the competition.