New Project - Portable fully suspended ebike

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
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Cambridge, UK
Oops I was thinking about my Brompton bag which is heavier at around 3kgs. The rucksack is probably nearer 2kgs. I think the umbilical approach works well on these portable projects.

If I put the controller in that black tool bag in the frame then the rucksack could just have the battery in it and leave even more space for luggage.

Check out Klickfix for detachable luggage options, not cheap but works well.

PS those lipos give you way more range per weight than my A123s.

Regards

Jerry
 
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cwah

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Jun 3, 2011
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Jerry, this is amazing!! This is exactly what I have to do with my bike.

Actually for my actual bike the frog case is completely broken, so it's one more reason for me to do that:


Conhismotor doesn't want to replace it. I don't know why I believed in their fluffy 2 years warranties.. my mistake :(
So it's time for me to change that and put everything in a backpack (to prevent thieves in London anyway).

If I just purchase the plastic box and connector from Maplin, could I do the same for my bike? And by the way how did you make the holes in the box?

Thanks and regards
 

cwah

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Jun 3, 2011
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Yes, I could simply buy a new frog case. Or I can take this opportunity to do put the controller and battery directly in a backpack (for thieves)

ps: sorry for spamming your post Jerry
 
D

Deleted member 4366

Guest
Yes, I could simply buy a new frog case. Or I can take this opportunity to do put the controller and battery directly in a backpack (for thieves)

ps: sorry for spamming your post Jerry
Having a 10aH battery in a rucksack is not as good as it sounds. I tried it and found two main problems: Firstly, the weight gets to you after a while. You put the battery in your rucksack and it feels Ok, but on a longish journey it starts to become annoying. Secondly, it's not easy to connect/disconnect the wires unless A. you're a contortionist B. you have long wires that hang untidily out of your rucksack. Also you'll have to think about where to fix your controller. You could get one of these:
KU63 Controller Case - BMSBATTERY
and then mount the battery in a football boot bag held on a rear rack with bungees. You'd only have one connector then to remove the battery in its bag, which would have a nice strap for carrying it.

The frog battery is one of the most secure locking systems. It's very difficult to remove without a key. Most of the other types can easily be levered out of the locking mechanisms without a key.
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
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ps: sorry for spamming your post Jerry
No problem. The post is about portable ebiking as much as anything else.

The holes where drilled using a mixture of these



The larger ones are called hole saws as shown on the right.

Regards

Jerry
 

cwah

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Jun 3, 2011
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THanks D4veh,

Actually, I'm now planning more to just use the backpack to carry the batteries with me when I leave the bike. When I'm cycling I think mounting the batteries in the rear rack would be much more convenient.

You said it's very difficult to remove the batteries without a key, but if I was a thieve, I would just remove the whole part (Controller + batteries) fixed to the seat tube. Just a screwdriver should be enough to do that.
Do you think that would be something too long to do for thieves?

Jerry, thanks for the drill pictures. I'm not sure I want to buy all of these yet. Still looking for simple way to do that lol.
 

jerrysimon

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Aug 27, 2009
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Cambridge, UK
Jerry, thanks for the drill pictures. I'm not sure I want to buy all of these yet. Still looking for simple way to do that lol.
I only used the the last two shown. You could just use a regular drill bit (the biggest you have) and then a hand file to enlarge the holes to the right size.

That is how I did the battery case a while back, but it is neater to drill them on complete.

Regards

Jerry
 
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D

Deleted member 4366

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You said it's very difficult to remove the batteries without a key, but if I was a thieve, I would just remove the whole part (Controller + batteries) fixed to the seat tube. Just a screwdriver should be enough to do that.
Do you think that would be something too long to do for thieves?
.
You need more than a screwdriver. First you need a screwdriver to remove the plastic side-panels. There's also 4 very small screws that are difficult to get at (if you still have them) with small nuts on the back. OK, if you had a big screwdriver, you could probably lever off the plastic so that it breaks. Once the plastic is off, you then need a 10mm spanner to hold the locking nuts on the main clamp while you unscrew the the four screws, which takes quite a long time. Then you have to prise the clamp apart befor you can remove the whole mounting system, which is still joined by all the wires, so you need cutters.

Unless a thief has actually removed one of these before, he'd probably give up after trying to lever the battery off.

As far as I can see, yours is mounted to the frame, so all that I've above applies. Some people clamp theirs to the seat pin, so it's only as secure as the seat pin, in which case it would be much more secure if you changed the quick release clamp for a tamper-proof screw and locking nut.
 

cwah

Esteemed Pedelecer
Jun 3, 2011
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Thanks Jerry and Flecc. For now I'm not ready to invest in an expensive drill for few holes. But is a drill like this ok?
Dremel Drill Press Stand Workstation Rotary Tools 220 | eBay

D8veh, thanks a lot your detailled explaination. I'm maybe don't need to remove my battery from my bike everytime I leave it on the street then. But still I have the impression that my frog battery is fragile. (and the plastic box is now completely broken)

----

By the way Jerry, this post is a reference for me and I'm going to try to do what you did so neatly :)
 

Scottyf

Esteemed Pedelecer
Feb 2, 2011
1,403
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I also liked the battery in a back pack as it made the bike feel more balanced and also meant I carried both my controller and batteries when I left the bike.

Mean once I parked it up in Birmingham it just looked like a standard bike and allowed me to walk away with the dangerous and expensive parts. I used andersons for quick connectors grouped onto each other.

Love the bike jerry and the setup.
Hope it works well and comfortably! Still low weight too!

Love it
 

morphix

Esteemed Pedelecer
Oct 24, 2010
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Worcestershire
www.cyclecharge.org.uk
Having a 10aH battery in a rucksack is not as good as it sounds. I tried it and found two main problems: Firstly, the weight gets to you after a while. You put the battery in your rucksack and it feels Ok, but on a longish journey it starts to become annoying. Secondly, it's not easy to connect/disconnect the wires unless A. you're a contortionist B. you have long wires that hang untidily out of your rucksack. Also you'll have to think about where to fix your controller. You could get one of these:
KU63 Controller Case - BMSBATTERY
and then mount the battery in a football boot bag held on a rear rack with bungees. You'd only have one connector then to remove the battery in its bag, which would have a nice strap for carrying it.

The frog battery is one of the most secure locking systems. It's very difficult to remove without a key. Most of the other types can easily be levered out of the locking mechanisms without a key.
The way I've approached it is something similar to what d8veh has suggested.. I've just used a decent roomy handlebar bag (very cheap off eBay approx £6) and it holds my controller and 10Ah 2.3kg battery. I don't need to remove mine as I never the leave the bike outside anywhere, but if I did, it would be easy enough to adapt the bag to make it removable using quick release buckles attached to some strong nylon webbing straps. Then you could either make a shoulder strap that snaps onto he buckles, or just stick the whole thing in your rucksack.

I don't find the weight a problem at all on the front of the bike, but saying that I have a full size 26" folding MTB, it might be different on a smaller 20" bike.

I initially opted for 5Ah LiFePo4 batteries at 1.9kg to keep the weight down, but since Lithium-Ion 10Ah is only 20% heavier I've switched to that now for the extra performance boost and distance.
 
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jerrysimon

Esteemed Pedelecer
Aug 27, 2009
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Cambridge, UK
Just to complete this thread. I have since upgraded the rear S2C hub to the recently released SRAM Automatix. A much better implementation of a two speed hub.







Regards

Jerry
 
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andyh2

Esteemed Pedelecer
Jan 8, 2008
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Tell us more about the SRAM automatix please and how is it better than the SC2?