First build project review

[Korax]

Hi folks!

After months of research, i am ready to start my ebike diy project. What I would really apreciate from this community is a little review just to know I am not making some huge mistake of if something could be improved.

I will use my bike for commuting, a 18 km round trip twice a day (I will be able to charge the battery any place I will be). Roads are flats, I don't expect to make a lot of off road with it. What I'm looking for is good speed and enough range (40km will be apreciated)

So, here we start.

I own a fat bike steel framed, 26´ wheels, discs brake, basic but sturdy.

The rest of the parts will be:

1000w hub motor kit from Luna cycles with 25A controller.
https://lunacycle.com/fat-ebike-kit-1000-watt-waterproof-connectors/

The battery will be a DIY 52V 20mAh 14s4p of Samsung INR21700-50E (5000mAh - 10A, enough for the controller)
https://eu.nkon.nl/rechargeable/21700-20700-size/samsung-inr21700-50e.html


They will be spot welded with the Kweld spot welder (Looks like a good one but i'm still looking those cheap chinese sunkko as well)
https://www.keenlab.de/index.php/product/kweld-complete-kit/

What do you think of this build? Any known issue with any of these parts? Am I missing something?

I was also thinking ok using a Mxus 3000w hub motor but I will also have to upgrade the battery and I think it will be a little bit overkill for my needs.

Thanks guys!!

 

[dogman dan]

Battery will be big enough, but it would most likely last longer if you made it 6p, because the discharge rate per cell will be lower. And have less sag, which is nice for the rider.


As for the kit, plenty of power and speed for fat tire bikes. More would not be ideal, since fat bikes are not meant to be ridden at motorcycle like speeds. Go with fat moped rims and tires if you want that later on, on another build.

 

[Korax]

Thanks for your advice, I'll have a look to the extra batteries.

I don't quite understand what you suggested about the rims. Did you mean use a specific moped designed rim for my build?

 

[neptronix]

Yeah basically fatbikes don't tend to handle very well at high speeds because of the tire shape ( it deforms and interferes with turning and balance )
The wider it is, the worse things get.
Best kind of tire size for snow and sand.. not so great for high speeds.

The kit is okay, you'll notice the brand names of the components are censored. Well, you get what you pay for at that price.

Building your own battery is a smart idea, but if this is your first ebike you've ever built, the total learning curve might be pretty high as it involves building a battery from scratch, perhaps the first time?
If first time, just keep in mind that battery building is kind of a science and there's lots of ways to do it wrong. You will need to invest in a lot of tools and knowledge-time. This makes sense though if you plan on building batteries in the future.

I really like em3ev for batteries if you chose the prebuilt route over building. But building is a nice skill to have.

 

[Korax]

Well, you re starting to scare me about the fat bike thing Will I loose so much speed?

For the battery I am decided to do it myself, maybe I won't even make another one but i am willing to take the diy road on this one. Thanks for the advice though !

( Ps: I had a look to em3ev, they sure have good stuff )