Waterproofing hub motors?

[thelarkbox]

I am a newbie but i did perform a forum search for waterproofing before i decided to post and all i got was battery stuff (at the top at least..)

My rear hub motor isnt waterproof the suppliers web site points it out.. and although the bike lives in a garage overnight usually it rains a lot here..

A few US utube vids detail sealing direct drive hub motors with a hi temp lacuor or conformal coating, with some even adding ferrofluid to aid heat transfer. But my 250w hub motor is significantly smaller and contains gears too??

Is a squirt of wd40 every week or so suffice or are more drastic measures worthwhile??

I am a slow on road cyclist not a rough and wet terrain mountain biker..

thanks in advance..

 

[davell]

As long as you don’t submerge the motor and the cable goes downwards where it leaves the hub then you shouldn’t really have any issues.

 

[thelarkbox]

As long as you don’t submerge the motor and the cable goes downwards where it leaves the hub then you shouldn’t really have any issues.

Cheers , even though i know how unreliable utubes can be they have provided me with most of my ebike info to date

The cable leaving the motor struck me as vulnerable so i added a bit of heatshrink..

 

[saneagle]

There are two things you need to do to keep your hub-motor dry:
1. Make sure that the cable exits the axle downwards.
2. Seal the disc screws if the holes go all the way through. Some motors have blind holes, so that's not necessary.

From your photo, it looks like you have your cable exiting upwards. You must take the motor out and turn the axle up the other way. The heatshrink you've put on won't save your motor. It might even make it worse. It's also useful to squirt some silicone grease into the axle, where the wire goes, as an additional precaution.

To seal the disc screws, you can use Loctite, Hermatite, Instant Gasket, silicone sealant or anything like that. before doing that, take one screw out and see whether the hole goes all the way through. Some do and some don't.

 

[thelarkbox]

There are two things you need to do to keep your hub-motor dry:
1. Make sure that the cable exits the axle downwards.
2. Seal the disc screws if the holes go all the way through. Some motors have blind holes, so that's not necessary.

From your photo, it looks like you have your cable exiting upwards. You must take the motor out and turn the axle up the other way. The heatshrink you've put on won't save your motor. It might even make it worse. It's also useful to squirt some silicone grease into the axle, where the wire goes, as an additional precaution.

To seal the disc screws, you can use Loctite, Hermatite, Instant Gasket, silicone sealant or anything like that. before doing that, take one screw out and see whether the hole goes all the way through. Some do and some don't.

Cheers, Im pretty sure the cable is exiting down and its bad photography making it look otherwise to you, I dont think that heat shrink can shrink that small as to squeeze the cable how it looks.
I had it pointing up and backwards on the first fit So have already tried to fix that once by rotating the axle 180 degrees and swapping the lugs around.. But I will check and confirm tomorrow.

My track record tells me with all things new if i could screw it up the chances are i did screw it up ..

the heatshrink can come off easily enough and grease can go in too

And i shall check the disk screws and seal if not blind too thanks..

That cable looks like its coming out the top to me too now wtf?

 

[saneagle]

Cheers, Im pretty sure the cable is exiting down and its bad photography making it look otherwise to you, I dont think that heat shrink can shrink that small as to squeeze the cable how it looks.
I had it pointing up and backwards on the first fit So have already tried to fix that once by rotating the axle 180 degrees and swapping the lugs around.. But I will check and confirm tomorrow.

My track record tells me with all things new if i could screw it up the chances are i did screw it up ..

the heatshrink can come off easily enough and grease can go in too

And i shall check the disk screws and seal if not blind too thanks..

That cable looks like its coming out the top to me too now wtf?

Just another thought. If you have angled drop-outs, it'll go sort of down and forwards. There's not much you can do about that other than try to force a drip loop by tying the cable in the right way. Again, the photo isn't very clear, but it looks like you have vertical drop-outs.

It's better when you have a motor with the cable exit on the other side because you don't have the derailleur in the way.

 

[thelarkbox]

Yeah the drop outs slope and ive had the drip lip instruction from a builder pal many many moons back the lowest point of that cable is just before it hides behind the frame.

Again its the photo angle there is no problem with the derailleur no cable/lead clashes.

I couldn't take a more misleading pic if i tried. HA

 

[Nealh]

No need to to use extra heatshrink over the motor cable, simply make sure a drip loop is part of the cable connection/set up and use the axle cover/cap. As already mentioned one can apply some grease via a syringe to the cable axle entry but often the fit is snug, the rotor holes is a good point and worth checking .

I have ridden my hub bikes for many years in all weather and still do as it is used for 99% of my road use, I have even ridden thru water over the axle and not had motor issues even after opening it to replace a noisy bearing the inside was spotless.

We have seen some dire lokking hub internals (one recently on the forum) , the main cause of rust /seizure is mostly down to the motor cable exit angle and water tracking in over a period of time.

 

[thelarkbox]

Well Flabber my Ghast!! When i pottered into the garage this morning i took off the heatshrink and stared at the exit cut out on the axle pointing STRAIGHT UP!!

THANK YOU ALL for prompting me to check..

And to make sure i have bugger all confidence left in my recall the frame slots do indeed point straight down and are NOT at an angle????
View attachment 53529
So thats now corrected!! And the disk anchor holes are not blind so I shall seal those too..
Thankfully no conflict with the gears..


Now i am totally confused as my first fit had the wire poking back and up and leaving it like that would have resulted in the motor connection sitting under the bottom bracket I know i tried routing the flex.. at which point i realised the thing needed flipping and i did flip it??

Thanks for the reassurance @Nealh Most my info has come from the entertaining utube vids i have scanned over the years lurking in the wings of the ebike subject. Then during my wheel fit i came across lots of rust starting to show on the cheaper steel fittings on my 4yr old bike.. Just like in the 'hole' above the wheel nut in the pic above..

So im glad to be proven Very misinformed on this one, But am mighty glad i asked as otherwise my wheel cable cockup could have gone unnoticed and become a real issue..

thanks again

** EDIT Thought I had posted this yesterday?? Pic linked not on this computer will add later..

 

[WheezyRider]

You mentioned in one of your posts squirting WD40 into the motor. Don't ever do that, the risk is you will dissolve the grease in the bearings, leaving them to run dry.

 

[thelarkbox]

You mentioned in one of your posts squirting WD40 into the motor. Don't ever do that, the risk is you will dissolve the grease in the bearings, leaving them to run dry.

Damn!! IM glad you dropped by to contribute as guess what i was gonna do once I had done the loctite and grease job amazon deliveries expected tomorrow..

 

[thelarkbox]

Amazon dropped the ball, but the grease arrived this morning so i attempted to pack as much as i could around the flex feeding into the wheel hub using a small a small flat head screwdriver as a spatula.

I then as suggested thread-locked the screws on the disk brake fitting too.

Cheers.