Can I fit a light weight battery to my Decathlon 500e pedelec

peterjd

Pedelecer
Sep 18, 2019
195
46
I like most characteristics of my Decathlon Riverside 500e bike except the weight of the 11Ah battery for short rides. Is there anyway of substituting with one of my lightweight 2.6 or 5Ah 36V batteries (+ separate controller if necessary) for such rides? I don't want to invalidate the warranty by dismantling any of the existing 500e setup. Peter
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,158
8,236
60
West Sx RH
Tbh looking at the bike not worth the hassle of trying to rig up such a change.
By the time one tries to house a controller somewhere and the battery one isn't going to save much on weight or elegance.

If one had no warranty remaning then a pair of fly leads from the battery controller base would be easy to sort out , but might depend on if it needs to see othe rbatteyr comms.
 

Bonzo Banana

Esteemed Pedelecer
Sep 29, 2019
740
432
While the connections may not be fully proprietary the battery and controller case is so it would be difficult to do. I feel if you have space you would be better off getting another bike and converting that to an ebike. If weight is a concern then perhaps a low weight road bike with steel forks and a front hub motor conversion with a small 250W hub motor and low capacity battery. You should be able to drop a few kg over that decathlon bike. Looks like the Decathlon bike is 22kg and a low weight road bike with steel forks could be as low as 11kg and a lightweight conversion might get you to 15-16kg so a possible 7kg weight saving over the Decathlon bike.
 

saneagle

Esteemed Pedelecer
Oct 10, 2010
4,274
2,106
Telford
You could save more weight more easily and probably cheaper by swapping pedals, seat, stem and handlebars for lightweight ones, and/or you can get some decent air forks that would give you a better ride too.

If you really want a lightweight bike, get yourself a reasonable used roadbike with disc brakes, change the bars to straight carbon fibre ones. Get a set of used shimano combined shifters and hydraulic brakes, then fit a Q100/AKM100 rear motor and a 5ah downtube battery from Aliexpress. You should be able to get rown to about 16kg or less.

Here's one I did, now with rear motor instead of front:
57277

57278
 
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peterjd

Pedelecer
Sep 18, 2019
195
46
Thank you all for the sensible advice. I'll stick with my converted (cadence) old tourer for local rides and use the more relaxed ride of the torque controlled Decathlon for the longer ones. I think it was more the desire to know how the Decathlon is put together eg the torque system than a real need. Incidentally it is good at restarting on a hill - the power comes on almost immediately - provided a suitable low gear has been selected before stopping. Peter