South America mid drive e-moto

trazor

100 W
Joined
Jan 13, 2015
Messages
171
Hi, i'm Eduardo from Uruguay. This is my first post on ES, but been reading for years.

I want to show this video that a friend made while I was playing at my neighborhood fields.



This is a very rough build, using a DHish steel frame, custom chainstays tig welded by myself , lightningrod's big block motor, lipo batteries 72v, karting 219 transmission, kelly KBS, zoom cheapo DHish fork.

This bike was previously rode with a "DongDiang" MXUS3k clone and I destroyed the rear wheel with some weeks of jumps.

I don't have photos now and the day is cloudy. I can take some if somebody wants to see the details of this third world build.

I would take the opportunity to thank all the people here, you all make a great resource to tinkerers/builders around the world.
 
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Cool video! Looks like a nice build. I'd be curious to see some pictures of your bike when you are able to take some. I would be careful with those zoom forks...especially jumping. For street riding they are probably alright but I wouldn't trust them for much else. I have a friend that has them on his enduro bike with cro motor. I have noticed a good amount of flex, especially under heavy braking in the front which is a bit scary.
 
Good work with a quite functional result. It always cracks me up to see that little motor called a "big block" motor, so I had to post a comment. You did a good job getting the most out of it, regardless of how funny I find its name.
 
Awesome video! I need to record stuff like that.

And i also use that motor it is a beast! Dont let the size fool you :)
 
Yes, nice building, riding and recording!!!! Ime the bht (similar size/weight to bigblock) surpasses 40 lbs of hub motors for these activities. I consider it ridiculous no businessmen have tapped into this middrive-direct (direct middrive?) potential- though it's warranted hubs are easier and thus more profitable. But cheasier haha- Nice job man.

Also, I don't call that third world- that place looks beautiful and I bet it's that way far longer of a year than where most of the population dwells. That should be first world and to the north should be 2nd and 3rd/ / / Enjoy it, as you are!
 
jansevr said:
Thanks for the pictures! Nice work! Glad to see you have upgraded your fork, I've used an old Marzocchi 888 and the 380. Much better than Zoom. It also appears that you have potted your BMS? Good idea, can't say I've seen anyone else do this. What did you use?

The Marzocchi fork is fairly new but I'm not very happy with build quality since it broke after a jump. I've heard a "tok" sound and after that I lost the rebound/compression action. Dissasembled the leg (scary situation since never done that and it is a shiny new 500usd part), Marzocchi does not make maintenance manuals, so I was going blind. I've found that a snap ring loose on the low part of the bottle. Went to the moto store and brought 7.5w fork oil and re-assembled. Tough process, had to dig youtube for leaked videos of the maintenance courses for old forks. I've dialed the compression/rebound to lower values, hoping for the snap ring to stay in place.

Analyzing the fork construccion, looks like these forks are shaved a lot of material. I mean, using a snap ring instead of 1/4inch screwed aluminum cap is a measure to save weight. I think that the best forks for these kind of "e-motos" would be the older ones weighting 3.5kg or more. A lot of people uses the DNM air forks, but air leaks... I prefer springs. Any recommendation for next e-moto?


About potting the BMS, i've used epoxy resin, you can buy it in "fiber glass" shops.
Potting started after a crash that destroyed my "dashboard", I liked it and began to pot all I can to add strenght. Here is my new dashboard in epoxy resin too
IMG_20171202_183132.jpg

The device is: https://www.amazon.com/bayite-BAYITE-PZEM-061-Multimeter-Voltmeter-Transformer/dp/B00YY1KOHA/ref=sr_1_3?ie=UTF8&qid=1512251531&sr=8-3&keywords=watt+meter+100A

My process to pot is:
1. Measure part to be potted
2. Make a cage from PET sheets
3. Cover connectors with any kind of clay
4. Put part and pour the resin
5. After resin being cured take out (maybe break) the PET cage.
6. Take out/wash clay
 
Nice build trazor, nice to see you aren't scared of The Fuzz with your 72V multi kw setup in South America, maybe when they want to puff out their chest, its only a matter of flinging a few bills their way.

Whats the motor sound like when riding casually?
 
markz said:
Nice build trazor, nice to see you aren't scared of The Fuzz with your 72V multi kw setup in South America, maybe when they want to puff out their chest, its only a matter of flinging a few bills their way.

Whats the motor sound like when riding casually?

Thanks :D
I try not to use it on streets, just offroad fun. For transport I use couple of e-bikes.
If you wonder how this bike sounds, check this video, it is 360 so you can look around.

[youtube]7YO6QAL7AyU[/youtube]
 
Great Job! I'm working on similiar project and i have some questions:
1 - what motor was used to bulid it and hou it works? Is it strong enough?
2 - what size of pipes (wall thickness) was used?
 
kcr said:
Great Job! I'm working on similiar project and i have some questions:
1 - what motor was used to bulid it and hou it works? Is it strong enough?
2 - what size of pipes (wall thickness) was used?

Hi kcr,

Thanks!

This thread is old and the e-moto you can see here is a very early prototype of what then became "OpenEmoto" project. Here you can see the thread https://endless-sphere.com/forums/viewtopic.php?t=92563 .

1 - Prefered motor is Denzel 4500 found on eastgem.net (seems store is closed momentarily). 92/12 tooth ratio. Crazy strong, 50Km/h max (my ride style requires torque over speed)
2 - Pipes are 2mm width. Can't get more stronger than that. Probably this can be done with 1.6mm or 1.2 cromoly. I'm using mild steel. Never had a frame failure yet.

Here is a youtube channel too with a lot of recorded material on how I construct every part (subscriptions welcomed): https://www.youtube.com/channel/UCxQhyZTLAw3pfvJFZXAff8w
 
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