Making E-bikes rain / water resistant, waterproof

spinningmagnets

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I always suggest to avoid riding in the rain, even when basic precautions have already been taken. However, it's not unreasonable for someone to ride to work when there is no rain in the forecast, but then to get caught in an unexpected downpour on the way home.
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Hall throttles

I recently stumbled across ES member gwhy suggesting that hall throttles be partially dis-assembled, and the bare solder connections be sealed with some type of epoxy or paint (perhaps clear nail polish), and the alternate suggestion posted was to use a non-conductive dielectric silicone grease to pack the internal parts (or do both?). Perhaps seal with nail-polish/epoxy, and then pack with silicone hardening sealant/rubber?

Small packets of silicone grease the size of your finger can be found in most automotive electrical sections at a car parts store. Silicone grease retains its viscosity from -40F to over 300F http://www.w8ji.com/dielectric_grease_vs_conductive_grease.htm

http://endless-sphere.com/forums/viewtopic.php?f=2&t=60534#p904590
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From Fechter:
Some throttles will sort of short out if they get too wet inside. Where the cable enters the throttle body, there is often a small plate held on with a screw that can be removed to gain access to the wire connections inside. The actual hall sensor is waterproof, but the 3 wires going into it are often exposed and can be bridged by a drop of water, causing the motor to run with the throttle at zero. If you can seal the area between the hall sensor and the 3 wires, the whole thing should be submergible. I used a little fingernail polish to soak the area. Runny epoxy would be good too.
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Hub motors

Water gets into hub motors and causes rust, even if it is just from humidity. E-bikes in rainy and humid weather are encouraged to dis-assemble their hub-motors and coat the insides with some type of rust-proofing. An interesting side note is that in the thread about ventilating a hubmotors side-plates to let out the built up heat (to allow more amps), it was noted that when the stator gets hot, any moisture evaporates and easily leaves through the vent holes, so...it's apparently just as important to create an available exit for moisture as well as trying to keep it out?
http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=25#p537517
http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=150#p550168

http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=75#p545662
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Battery

It is vital to keep the battery pack and its BMS dry, but I have no specific advice just yet. However...this is probably the most expensive water damage you will experience, so something really needs to be done.
 
Bionx - Good quality parts and electrical connectors. Controller is inside the motor. I have ridden in some serious rain till my underwear was wet. Bike works perfectly. That was years ago. Also storing bike indoors is best. Now I see a new web site:
http://ridebionx.com/
Motors and everything else looks different. Hope they still work in the rain.
 
Good Stuff SM!

Question, though: I've heard from some who've tried cooling oil, that it seems to "wash" the rust off. However, once you do that, applying varnish is a no-go, as it probably won't ever stick to the stator. I'm going to crack open my motors - if they are reasonably rust-free, I'll use varnish. If I find they are bad rusted, then I'll skip that and go to oil.

Any thoughts about oil vs. the varnish?
 
Any thoughts about oil vs. the varnish?

As a young hydraulic mechanic many years ago, I was shocked to see rust inside a hydraulic ram that was drained and dis-assembled. I was told that water had several routes to get into that particular system, and even when the internals were bathed in oil, the particles of water that were mixed in with the oil will still cause rust.

That being said, I am sure a hub with 1/3rd of its internal volume filled with oil will not have any issues with rust, since the heat will evaporate any water that inadvertently gets in. The rusty hydraulic ram in my example ran fairly cold.

if they are reasonably rust-free, I'll use varnish. If I find they are bad rusted, then I'll skip that and go to oil.

Sounds like a good plan to me!
 
Was looking for the link to properly credit gwhy! and found this on the "extra water resistant" Domino throttle. It apparently also has a softer rubber compound than the Magura that some riders find to be more comfortable, and the range of twist is also a more comfortable 60-degrees instead of the Maguras 75-deg.

http://endless-sphere.com/forums/viewtopic.php?f=10&t=58516
http://evmc2.wordpress.com/2014/03/30/5k-ohm-throttles-domino-vs-magura/

dsc4262.jpg


For riders who purposefully ride in extra wet conditions, one thread talked about using a motorcycle cable throttle, and placing the electric elements inside the controller (just a thought, please add a link if you find that). From gwhy! and others:
https://endless-sphere.com/forums/viewtopic.php?f=2&t=56511#p842300

Heres an alternative attempt at the same thing
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=2522
 
Here is Hannes' (izeman) custom build. The 12-FET controller is mounted to the front of the battery box for air-cooling. Notice there are no wires coming out of it? He slid a 9-FET into the housing for a 12-FET, so that there would be some internal room for routing the wires straight into the battery box. He may have done this partially for a more uncluttered look, but the waterproofing is what caught my attention, and easy to do. Maybe put a 12-FET inside an 18-FET case?

http://www.electricbike.com/hannes-crossbreak-style-mid-drive/
IzemanCrossbreak3.png


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Water ingress can cause a short, I recommend a breaker that Teklektik researched (he's an electrician).

http://www.electricbike.com/teklektiks-dual-motor-yuba-mundo/

Alan used a 50A magnetic marine breaker for the main power disconnect switch (Blue Sea model #7230). These types of breakers are very rugged and are intended for high-humidity/salt-air use. They are designed for up to 65V-DC and can handle interruption currents up to 7500A making them virtually indestructible in this application. “They start to trip at 62A and with a couple of controller shorts, the CycleAnalyst never recorded a spike greater than 180A before the breaker switched off”.
 
"Weatherpack" brand connectors are made for boats and cargo trucks that are guaranteed to get wet. if you needed two posts on a connector, and the Weatherpack pins are too small, consider getting a 4-pin connector and pairing them to double the amp capacity.

file.php
 
spinningmagnets said:
"Weatherpack" brand connectors are made for boats and cargo trucks that are guaranteed to get wet. if you needed two posts on a connector, and the Weatherpack pins are too small, consider getting a 4-pin connector and pairing them to double the amp capacity.

file.php

This looks good for phase wires, better than an A-P if they can be had with enough current capacity...
 
All my ebikes use Delphi WeatherPack connectors, I ride in rain every fall and spring a lot, they will never be penetrated by water, no way.
My Eplus bike is 100% rain-proof, zero silicone used, just quality el. components including rock solid throttle.
 
My throttle used to get stuck in full when it got wet. So I opened it up and sprayed neverwet in there and it never happened again.
 
For motor, brake, throttle, CA connections etc., I mostly use old inner tubes to protect from water. Much cheaper and less bulk than so called "waterproof" connectors.

Throttle - 'use a plastic bag for heaviest downpours and AVOID using those integrated throttle+fuel gauge handlebar controls. 40-80VDC pack voltage in close proximity to throttle signal wiring under wet conditions is just asking for trouble, IMO.
 
If you do need to use one of the combo throttle/batterymeter units, you can make a simple resistive voltage divider to drop it down to within the ~5V range, down at the battery/controller end of the harness. Probably for most poeple still using those, they've got less than a 60V-full battery, so you can use a 1:10 ratio divider.

Then open the battery meter part up, and change the resistors in it by the same ratio your divider is, so that the voltage reference it's looking for on each one of it's comparators is now low enough to work with the new voltage input range. Each one of these is a little different so you'd have to trace out the circuit to see which resistors to change on yours.





Another option regarding connectors and waterproofing is to not use connectors at all, and to directly solder everything together, covering with heatshrink/etc at all the joints. :) Not only does it eliminate many water-ingress problems, it also means no worries about loose pins/contacts/etc. (which cause so very many problems we see around here). Another issue it eliminates is that of where to put all those extra feet of wire kits often come with.

To make this practical sometimes extra loops of wire may be needed at the wheel end of harnesses, so hubmotor wheels can still be relatively easily removed for service, especially for roadside repairs.



Using drip loops and such for areas where water ingress cannot be fully prevented can also help.
 
spinningmagnets said:
I always suggest to avoid riding in the rain, even when basic precautions have already been taken. However, it's not unreasonable for someone to ride to work when there is no rain in the forecast, but then to get caught in an unexpected downpour on the way home.
___________________________________________________
Hall throttles

I recently stumbled across ES member gwhy suggesting that hall throttles be partially dis-assembled, and the bare solder connections be sealed with some type of epoxy or paint (perhaps clear nail polish), and the alternate suggestion posted was to use a non-conductive dielectric silicone grease to pack the internal parts (or do both?).

Small packets the size of your finger can be found in most automotive electrical sections at a car parts store. Silicone retains its viscosity from -40F to over 300F http://www.w8ji.com/dielectric_grease_vs_conductive_grease.htm

http://endless-sphere.com/forums/viewtopic.php?f=2&t=60534#p904590
file.php


From Fechter:
Some throttles will sort of short out if they get too wet inside. Where the cable enters the throttle body, there is often a small plate held on with a screw that can be removed to gain access to the wire connections inside. The actual hall sensor is waterproof, but the 3 wires going into it are often exposed and can be bridged by a drop of water, causing the motor to run with the throttle at zero. If you can seal the area between the hall sensor and the 3 wires, the whole thing should be submergible. I used a little fingernail polish to soak the area. Runny epoxy would be good too.
____________________________________________________
Hub motors

Water gets into hub motors and causes rust, even if it is just from humidity. E-bikes in rainy and humid weather are encouraged to dis-assemble their hub-motors and coat the insides with some type of rust-proofing. An interesting side note is that in the thread about ventilating a hubmotors side-plates to let out the built up heat (to allow more amps), it was noted that when the stator gets hot, any moisture evaporates and easily leaves through the vent holes, so...it's apparently just as important to create an available exit for moisture as well as trying to keep it out?
http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=25#p537517
http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=150#p550168

http://endless-sphere.com/forums/viewtopic.php?f=6&t=36375&start=75#p545662
file.php


file.php


____________________________________________________
Battery

It is vital to keep the battery pack and its BMS dry, but I have no specific advice just yet. However...this is probably the most expensive water damage you will experience, so something really needs to be done.


how do you open the throttle? do you have to slice it up? and which brand of silicone is the best for money?

thx
 
spinningmagnets said:
Was looking for the link to properly credit gwhy! and found this on the "extra water resistant" Domino throttle. It apparently also has a softer rubber compound than the Magura that some riders find to be more comfortable, and the range of twist is also a more comfortable 60-degrees instead of the Maguras 75-deg.

http://endless-sphere.com/forums/viewtopic.php?f=10&t=58516
http://evmc2.wordpress.com/2014/03/30/5k-ohm-throttles-domino-vs-magura/

dsc4262.jpg


For riders who purposefully ride in extra wet conditions, one thread talked about using a motorcycle cable throttle, and placing the electric elements inside the controller (just a thought, please add a link if you find that). From gwhy! and others:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=56511#p842319

Heres an alternative attempt at the same thing
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=2522

I have the Dominno throttle, its really good, the reason its weatherproof is because all the internals are set in epoxy just about, as I rewired the inside of mine and had fun. The grips are exactly the same as motocross ones.
 
Anyone that wants waterproof connectors for hall sensors etc just search for ip68 connector on ebay
 
These new Wuxing thumb-throttles are waterproof as far as rain/spray is concerned.

http://www.aliexpress.com/snapshot/6260703758.html

5d07d336e2b61f02978a4776fe686461_l.jpg
 
Like many builders here, I have a lot of the dirt cheap Hobby King color-coded heat shrink in many diameters. I was just now reading about "marine grade" heat shrink, which is used on boats. the HS is adhesive-lined, and once heated and shrunk onbto a wire/connector, it should be very water-proof. I have searched and found the best selection seems to be on EBAY, and marine heat shrink can be found in many colors...however, due to the higher price, i would recommend getting clear marine grade, of just black. For the clear, you can put colored heat shrink on before the cxlear, and for the bblack you can put the marine grade on first and the colored heat shrink on last.


http://www.ebay.com/itm/42Pc-Marine...615683?hash=item487ec6fe03:g:8QQAAOSwpDdVXVLL

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"Rain proofing your ebike - whos riding in the rain ?"
https://endless-sphere.com/forums/viewtopic.php?f=3&t=73442
 
I have two Giant Ebikes that have caused me 3ndless problems over the past 18 month. It seams the problem is getting water into the electrics which is a problem you have riding mountain bikes. We ride in all conditions then wash the bikes with hoses.
Would it be possible to seal all joints and switches and even the motor with a water proof spray. I remember years ago when cars came with proper distributors we used to spray them with stuff to stop them arcing out when they got wet. I have also used water proofing spray on my tent to stop water getting through the fabric. Could any of these sprays work on the wiring loom, switch gear and motor to cut down the amount of water getting into these parts?
 
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