2wd rear of delta or quad + suspension - will it work ?

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Paul,
Here is what we were discussing today. The same as Lotharko's jackshaft and freewheel(s) here is how it would work for you.
 
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Paul,
Here is what we were discussing today. The same as Lotharko's jackshaft and freewheel(s) here is how it would work for you.
Dan
Thanks for that I can see what it does from your video.

Remember I mentioned I was unsure how to line up 4 bearings for the jack shaft ? as the bearing mounts had small holes and not slots and little material to file slots in ?



Well led me to thinking about your differential which requires 2 separate shafts to work , they would be far easier to line up if there was a little play in the cross shaft coupling ?



Well I think I have slightly redesigned it to have a 8 speed cassette as the input and a coupler on the right shaft to a free wheel on the left shaft driving the free wheel teeth much like a chain would ?
So really just a 8 speed version of your diff ?
if it can work ?

Paul
 
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I have no idea how much this will affect matters but the more that is going to rotate on freewheeling then the poorer it will coast. The drawing above has the wheels driving two chains and two shafts. If you've ever tried to push a Land Rover (you can't!) you'll know what I mean. Less freewheeling equals more pedalling. The effect may be negligible or it may be important - I don't know.

Logic says that you have a perfectly good freewheel diff system with 2x fixies and 2x freewheels. You'd be saying no to this for a more complex system that works on exactly the same principle. In such a case even the "because I can" argument deflates somewhat.
 
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I have no idea how much this will affect matters but the more that is going to rotate on freewheeling then the poorer it will coast. The drawing above has the wheels driving two chains and two shafts. If you've ever tried to push a Land Rover (you can't!) you'll know what I mean. Less freewheeling equals more pedalling. The effect may be negligible or it may be important - I don't know.
This is the man who is building a 4wd + 4WS quad ? getting cold feet ? ;):)
I definitely feel I an treading a very fine line ? very few quads are built for pedal only and once you add electric assist for a lot of builds that also means throwing ' build as light as possible ' out of the window !

Logic says that you have a perfectly good freewheel diff system with 2x fixies and 2x freewheels. You'd be saying no to this for a more complex system that works on exactly the same principle. In such a case even the "because I can" argument deflates somewhat.
You mean option1 ?
I assume you are saying de-couple the wheels from as much of the chains and gearing as possible , so back to free wheels on the wheels.
I though I was just altering the order of the same components your saying there may be unwanted consequences ?
Paul

ps don't let DannyC see this !
 
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ps don't let DannyC see this !
Too late! :)
I don't disagree with the observation at all. The more stuff being "driven" while coasting the more energy is sapped from the system.
I'm sure I said the drawback was permanently driven chains while the vehicle was in motion.
I only suggested the "jackshaft located freewheels" as a possible configuration that would work (because it does). I agree the best solution is freewheels on the wheels themselves.

:LOL:(y)
 
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You mean option1 ?
1 or 2. Both work as a free wheel diff. No need to add snother diff on the jackshaft.

I take your point about my next build but that will have a motor and will not be a daily form of transport but a sunny Sunday ride and as such some issues are far more tolerable.
 
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Don't forget that if locating freewheels on the jackshaft they are driving, not being driven. In other words they need to be driven from the mount rather than getting driven from the teeth. This means mounting them onto threads mounted so the freewheel screws on from the left (still a r/h thread). This ensures the jackshaft turns the freewheel from it's centre.
 
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Ok dreamer meets engineer.....



I dreamed this up , would it work ?
So freewheel screwed to left hand side of a normal wheel , BMX with M14 axle so can just be bolted through a frame member.
Also bolted on by it's inner race is a large bearing i/d M14 , o/d as big as possible
between the 2 is a large core plug shaped piece like a washer with a big lip the size of the bearing width and the same diameter i/d big enough to clear any nuts on the shaft.
it is spaced as close as possible to the free wheel and this is free to rotate with the bearing outer race.
the free wheel unscrews till it reaches this core plug and then , stops unscrewing and resigns it's self to driving the wheel ....

Paul
 
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Do I understand you wright, you are using the large core plug and bearing to stop the freewheel unscrewing itself?
I can't see why it wouldn't work.
 
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The bearing cap / core plug would need to be made so it just contacted the freewheel when tightened up. The downside is the axle is then mounted further from the plane of the tyre meaning more leverage on the axle. Use as thin a bearing as you can find and I'd expect you'd get away with it from that point of view. But, the bearing itself is going to take some substantial side loading. Most std bearings aren't going to take such loadings so you'll probably need a taper roller bearing which are designed to take side loadings.

Don't forget to either space the other wheel off a similar amount or alter the chassis to compensate for the difference.
 
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Do I understand you wright, you are using the large core plug and bearing to stop the freewheel unscrewing itself?
I can't see why it wouldn't work.
Yes , it was the side loading I was worried about mainly

paul
 
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The bearing cap / core plug would need to be made so it just contacted the freewheel when tightened up. The downside is the axle is then mounted further from the plane of the tyre meaning more leverage on the axle. Use as thin a bearing as you can find and I'd expect you'd get away with it from that point of view.
True

But, the bearing itself is going to take some substantial side loading. Most std bearings aren't going to take such loadings so you'll probably need a taper roller bearing which are designed to take side loadings.
useful advice

Don't forget to either space the other wheel off a similar amount or alter the chassis to compensate for the difference.
Yes true, just a though I am a long way from needing this part to work , in fact I have just screwed it on for the time being , it will allow me to align stuff although I won't be able to put any load on it.

Seems I am building a shorter 2WD version of this :- Velomo hi-q3 the green one



Paul
 
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useful advice
OR, use an annular contact bearing they are built for side/end on-loads too. Used in Lathes and milling machines. 🆒
 
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A thrust bearing would be good and thin though a sealed unit would be better given the location. I use that same 3 piece type on my tilter but that doesn't see bad weather.
 
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