Frame Bracing a Folding Bike

General Discussion about electric bicycles.
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Ozzzz   100 W

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Frame Bracing a Folding Bike

Post by Ozzzz » Nov 11 2019 1:27am

hey I'm not sure if there is even a better forum to ask or get ideas from. I did search, i'm thinking others would have considered this, even done something similar.


I really like this little folding bike:
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I really want to move the battery into the frame.

Iv'e worked with fibreglass, to a lesser extent metals and to no extent - frame design. But can appreciate the stresses on the frame are taken up by the design and it would be possible to create more problems than it's worth.

Straight away, probably most obvious and making/ leaving room for a frame bag- I thought of a removable battery built inside an aluminium RHS top tube (where the red rope is.. but obviously to the frame not the head tube :shock: ..). This looks simple, and could be braced between two CNC clamp fittings. But even this simple design, will hard fixing points screw with the design?

Any other considerations or thoughts welcome.

I don't really care if it takes a bit more effort folding/unfolding. Folding needed but it's just for occasional bus travel.

I'm mainly thinking here, two birds with one stone, a battery in the frame that adds a safety margin to the frame join (and all that bending force this design has.

:?:
Last edited by Ozzzz on Nov 11 2019 1:34am, edited 1 time in total.

Ozzzz   100 W

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Posts: 183
Joined: May 03 2016 10:11pm

Re: Frame Bracing a Folding Bike

Post by Ozzzz » Nov 11 2019 1:33am

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Screen Shot 2019-11-11 at 5.13.38 pm.png (229.66 KiB) Viewed 345 times

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dogman dan   100 GW

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Re: Frame Bracing a Folding Bike

Post by dogman dan » Nov 11 2019 8:04am

The top tube of the typical frame is under compression when you load it. I have seen cable for the down tube, but not the top tube, which is not under tension load when riding.

Hillhater   100 GW

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Re: Frame Bracing a Folding Bike

Post by Hillhater » Nov 11 2019 8:27am

that modification wont work
Why do you think the frame needs strengthening ?
There are thousands of those bikes in use.no major issues reported..It is not intended for off road thrashing.
If you think or know, it is weak, pick another design. There are many folders with conventional diamond frame designs.
This forum owes its existence to Justin of ebikes.ca

Ozzzz   100 W

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Posts: 183
Joined: May 03 2016 10:11pm

Re: Frame Bracing a Folding Bike

Post by Ozzzz » Nov 11 2019 9:05am

Three birds, I want to move the/a battery, would like to use the space for a frame bag (as well), and was thinking any support in compression would only benefit this bike... ie. it's hinge doesn't have to bear as much constant bending force .

I'm not sure what 'wont work' about it? Iv'e seen some of these frames with poor welds, it wont help there?

An alternative, I considered was a full frame molded box, with the battery inside, this would only add stiffness to the whole frame?

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