As mentioned on another thread I have just installed a rear hub kit. How do people waterproof their wiring - are the plugs themselves good enough or should I use some self amalgamating tape ?

 

In fact, is it wise to avoid using the power during heavy rain and just rely on human power ?

hub kits don't suffer much if at all from water. You don't have to do anything, other than drying your bike after riding in the rain. The LCD is a bit more exposed, so keep the glass at an angle for the water to run off.

CD kits suffer much more from water because the controller is inside the motor which is mounted quite close to the road surface and often gets sprayed if not immersed in puddles. Water can also find their way inside the CD motor through the bottom bracket.

I used silicone grease from a diving shop - its a bit like vaseline but rubber and plastic safe and sheds water. Put it in the axle ends as well as wiring, battery charging socket etc

 

Did but some adhesive heat shrink (the properly waterproof stuff) but never got round to fitting it

I’ve just opened up my DD, and soaked the windings using an electrical spray that claims to repel water. After that then sprayed the windings with a insulation lacquer varnish.

 

Was an intention to add mineral oil. However, it’s yet to arrive.

 

 

I’ve just opened up my DD, and soaked the windings using an electrical spray that claims to repel water. After that then sprayed the windings with a insulation lacquer varnish.

 

Was an intention to add mineral oil. However, it’s yet to arrive.

 

 

[ATTACH=full]25232[/ATTACH] [ATTACH=full]25233[/ATTACH]

You might want to put a hold on oil cooling and look into using ferrofluid instead.

 

http://www.ebikes.ca/product-info/statorade.html

Edited June 13, 20187 yr by danielrlee

You might want to put a hold on oil cooling and look into using ferrofluid instead.

 

http://www.ebikes.ca/product-info/statorade.html

 

 

That ferrolfluid sticks to the magnates if I’m correct? What’s in ferrofluid to make that happen? Metal? Abbrassive ingredient?

 

Just collected the oil and it’s going in although only a small amount. Good enough for industrial transformer and motor cooling.

[ATTACH=full]25235[/ATTACH]

 

 

That ferrolfluid sticks to the magnates if I’m correct? What’s in ferrofluid to make that happen? Metal? Abbrassive ingredient?

 

Just collected the oil and it’s going in although only a small amount. Good enough for industrial transformer and motor cooling.

Don't get me wrong - oil cooling works a treat. It's just that the volume required is many orders of magnitude greater than required with ferrofluid and this creates unnecessary drag. Additionally, keeping the oil on the inside of the hub is a losing battle.

 

Ferrofluid contains nanomagnetic particles, far too small to abrase any of the motor components. The specific formulation is extremely important when it comes to this application. I'm fairly sure that the formulation used in 'Statorade' is Ferrotec APG1110.

 

Justin, the pioneer of ferrofluid hub cooling has tested motors for 10's of thousands of miles without adverse effects. The only concern might be the waterproofing measures you have already applied.

 

See the following thread for further information:

 

https://endless-sphere.com/forums/viewtopic.php?f=2&t=48753

Edited June 13, 20187 yr by danielrlee

Don't get me wrong - oil cooling works a treat. It's just that the volume required is many orders of magnitude greater than required with ferrofluid and this creates unnecessary drag. Additionally, keeping the oil on the inside of the hub is a losing battle.

 

Ferrofluid contains nanomagnetic particles, far too small to abrase any of the motor components. The specific formulation is extremely important when it comes to this application. I'm fairly sure that the formulation used in 'Statorade' is Ferrotec APG1110.

 

Justin, the pioneer of ferrofluid hub cooling has tested motors for 10's of thousands of miles without adverse effects. The only concern might be the waterproofing measures you have already applied.

 

See the following thread for further information:

 

https://endless-sphere.com/forums/viewtopic.php?f=2&t=48753

 

 

Seen a few ferrofluid reviews majority positive. The oil leakage issue is partly addressed with use liquid gasket.

 

I applied a lacquer thus the clearance gap between stator and magnets now less. Perhaps this will inhibit the application of ferrofluid?

 

I’ll keep the product on a list, a maybe for the next build. The present build is a prelude to another Ebike, something more suitable for off-road and with a branded more robust hub motor.

Edited June 14, 20187 yr by BG bicycle

Seen a few ferrofluid reviews majority positive. The oil leakage issue is partly addressed with use liquid gasket.

 

I applied a lacquer thus the clearance gap between stator and magnets now less. Perhaps this will inhibit the application of ferrofluid?

 

I’ll keep the product on a list maybe for the next build. The present build is a prelude to another Ebike, something more suitable for off-road and with a branded more robust and hub motor.

The exit route almost impossible to stop is via the motor cables. Give it time and you'll find that oil wicks through the wires via capillary action.

 

The lacquer won't stop the ferrofluid from working, but there has been anecdotal evidence to suggest that the base oil can react with some conformal coatings. The end result isn't that serious though. The conformal coating can dissolve, which gums up the ferrofluid, requiring removal from the hub and application of a fresh batch.

 

Mind you, I suppose a problematic conformal coating might suffer the same fate with mineral oil cooling.

Edited June 14, 20187 yr by danielrlee

The oil is in and a huge difference when free wheeling and when pedalling. Not that I do much of the latter, although the ease of turning that hub is greatly improved.

 

No oil leakage either.

Much of this discussion about cooling goes above my head. I think I read somewhere that Statorade is for non geared direct drive hubs. Don't know if this is true or not but in any case would someone who understands all this briefly explain it for dummies and would I, as a geared hub owner benefit from any of this technology ?

 

Many thanks

Paul

no need for coolant.

 

You can ride for hours and your motor is not even warm.

The geared hub motors do not suffer as much from overheating as direct drive motors because they are much more efficient at climbing hills compared to direct drive motors.

Higher efficiency means much less energy is converted to heat, there is no need to worry about cooling geared hub motors.

Much of this discussion about cooling goes above my head. I think I read somewhere that Statorade is for non geared direct drive hubs. Don't know if this is true or not but in any case would someone who understands all this briefly explain it for dummies and would I, as a geared hub owner benefit from any of this technology ?

 

Many thanks

 

Paul

Additional cooling of a motor is required when you want to push the power output past what can be sustained with natural cooling only. It is nonsense to state that any given motor type does or doesn't need it. If you want to eek the maximum performance out of any motor, it'll need additional cooling.

 

Ferrofluid works by bridging the gap between the motor windings and motor casing, providing a clear path for the heat to escape into the passing air. Direct drive (non geared) motors have a simple heat path, with only a single gap between the windings and magnets, which are coupled directly to the motor casing, so ferrofluid is extremely effective here.

 

Due to the complex heat path found in geared motors, ferrofluid is not sufficient to bridge this gap and therefore brings no benefit in cooling. An alternative (sealed method) for geared motors is oil bath cooling as used by BG bicycle above.

It is nonsense to state that any given motor type does or doesn't need it.

Paultr has an MXUS XF08C motor and a Lishui 17A controller.

That kit does not need coolant.

Paultr has an MXUS XF08C motor and a Lishui 17A controller.

That kit does not need coolant.

I certainly agree that a MXUS XF08C doesn't require additional cooling at 17A. That's not to say that it wouldn't still be beneficial in specific scenarios though.

 

If you were to fill one with oil, you probably be able to reliably run it at 30A. What's not to like (apart from the inevitable mess of course)?

 

Just to add that the discussion about cooling wasn't really directed at the OP, more a response to a tangent earlier on in the thread.

Edited June 17, 20187 yr by danielrlee

Additional cooling of a motor is required when you want to push the power output past what can be sustained with natural cooling only. It is nonsense to state that any given motor type does or doesn't need it. If you want to eek the maximum performance out of any motor, it'll need additional cooling.

 

Ferrofluid works by bridging the gap between the motor windings and motor casing, providing a clear path for the heat to escape into the passing air. Direct drive (non geared) motors have a simple heat path, with only a single gap between the windings and magnets, which are coupled directly to the motor casing, so ferrofluid is extremely effective here.

 

Due to the complex heat path found in geared motors, ferrofluid is not sufficient to bridge this gap and therefore brings no benefit in cooling. An alternative (sealed method) for geared motors is oil bath cooling as used by BG bicycle above.

 

 

If your hub motor holds the oil then anything that isn’t messy or going to create one and assists cooling is a good idea.

 

The bicycle I ride on with the motor 95% of the time steady 25-30kmh and although I’ve found no problem with heat, include the controller, the mineral oil has most certainly reduced drag. I do pedal on hills unless commute to town -one steep long incline- were power consumption from repeated travel is known.

 

The biggest killer of all electrical items is heat. If are able to install additional cooling method(s) then it’s advisable to do so. As for my own experiment time will tell.

 

BTW, Woosh, great name.

Edited June 18, 20187 yr by BG bicycle

I certainly agree that a MXUS XF08C doesn't require additional cooling at 17A. That's not to say that it wouldn't still be beneficial in specific scenarios though.

 

If you were to fill one with oil, you probably be able to reliably run it at 30A. What's not to like (apart from the inevitable mess of course)?

 

Just to add that the discussion about cooling wasn't really directed at the OP, more a response to a tangent earlier on in the thread.

the MXUS motor has an internal clutch and gearbox with nylon wheels.

Do you still maintain that Paul should use coolant?

the MXUS motor has an internal clutch and gearbox with nylon wheels.

Do you still maintain that Paul should use coolant?

I bet I could melt the gears without any problems. Which motor type should I use on ebike.ca to model the XF08C, AN XF07 only shows an efficiency of 64% with a 17a controller at 10% gradient with a 100kg load. That means 36% going to heat (150W), I'm sure a hub motor can't dissipate that much heat energy for very long!

I bet I could melt the gears without any problems. Which motor type should I use on ebike.ca to model the XF08C, AN XF07 only shows an efficiency of 64% with a 17a controller at 10% gradient with a 100kg load. That means 36% going to heat (150W), I'm sure a hub motor can't dissipate that much heat energy for very long!

 

you can use XF07 to model the XF08C. They are similar enough.

The motor can dissipate 150W OK, there is a considerable laminar flow of air around the motor. On some motors where the emulator has a heat dissipation model like 9Continent 2705 DD motor which in the same condition has a yield of 57% and overheats in 26 minutes. I reckon the XF08C would overheat in roughly 30 minutes, travelling at 10mph, that's a 5 mile long climb.

the MXUS motor has an internal clutch and gearbox with nylon wheels.

Do you still maintain that Paul should use coolant?

I've never said that Paul (or anyone else for that matter) should use coolant.

 

I do maintain that additional cooling will allow a motor run at greater power levels or loads than it was originally designed for, whatever the motor.

Edited June 18, 20187 yr by danielrlee

you can use XF07 to model the XF08C. They are similar enough.

The motor can dissipate 150W OK, there is a considerable laminar flow of air around the motor. On some motors where the emulator has a heat dissipation model like 9Continent 2705 DD motor which in the same condition has a yield of 57% and overheats in 26 minutes. I reckon the XF08C would overheat in roughly 30 minutes, travelling at 10mph, that's a 5 mile long climb.

There may be plenty of air flow around the motor but there is none around the windings which is why Statorade etc was developed. You need to shift the heat from the windings to the outside air to keep the motor cool.

There may be plenty of air flow around the motor but there is none around the windings which is why Statorade etc was developed. You need to shift the heat from the windings to the outside air to keep the motor cool.

it's just a theoretical risk. 10% gradient climbing at maximum power for 5 miles is 800m vertical, not likely found in the UK.

Realistically, have you come across any geared hub that died of overheating? Very unlikely. Magnetic fluid has its use but not in ordinary e-bikes otherwise Bosch would have used it for their CX motor.

BTW, DD motors have the same outer rotors like geared hubs, the heat dissipation model on the ebikes.ca is still applicable to geared hubs. ebikes.ca makes a lot of noises about magnetic fluid but all it does is to reduce the temperature of the air between the stator and rotor. When the air temperature reaches equilibrium, the same heat dissipation capacity of the motor stays more or less unchanged. If you change the motor for one with magnetic fluid added, time to overheating is unchanged on their simulator.

Edited June 18, 20187 yr by Woosh

Realistically, have you come across any geared hub that died of overheating? Very unlikely. Magnetic fluid has its use but not in ordinary e-bikes otherwise Bosch would have used it for their CX motor.

BTW, DD motors have the same outer rotors like geared hubs, the heat dissipation model on the ebikes.ca is still applicable to geared hubs.

I've destroyed 3, all by overheating due to running too much power, although the failure modes were not all the same. I'm positive that none of them would've failed with oil cooling. This of course ignores all the downsides to oil cooling, which I think outweigh the benefits for most people.

 

Ferrofluid is a totally different matter though. There are virtually no disadvantages to running 5-7ml in a DD hubmotor. As mentioned previously, small quantities of ferrofluid are ineffective in geared motors due to the complex heat path, which is why it is not used by Bosch, or anyone else.

 

FYI, Grin supplies all DD motors with Ferrofluid installed as standard.

I'm positive that none of them would've failed with oil cooling.

you can always put your theory to test one of these days.

The capacity of cooling is down to the design of the motor's casing, not influenced by the added thermal fluid, whether magnetic or not. It's just like your house radiator. You can use circulating water with or without additives, it's not going to change its capacity of heating.

it's just a theoretical risk. 10% gradient climbing at maximum power for 5 miles is 800m vertical, not likely found in the UK.

Realistically, have you come across any geared hub that died of overheating? Very unlikely. Magnetic fluid has its use but not in ordinary e-bikes otherwise Bosch would have used it for their CX motor.

BTW, DD motors have the same outer rotors like geared hubs, the heat dissipation model on the ebikes.ca is still applicable to geared hubs. ebikes.ca makes a lot of noises about magnetic fluid but all it does is to reduce the temperature of the air between the stator and rotor. When the air temperature reaches equilibrium, the same heat dissipation capacity of the motor stays more or less unchanged. If you change the motor for one with magnetic fluid added, time to overheating is unchanged on their simulator.

Bosch wouldn't need to use it, their motor is more likely to be spinning at a realistic speed. Air is a very good heat insulator, most home insulation products work by trapping air in a confined space so you will never achieve equilibtium, the windings will always be significantly hotter than the housing.

Btw I'm not advocating the use of ferro fluid or anything else just playing devils advocate because I know I couldn't use a hub motor here. Yesterdays ride had a 5km average 11% climb with an 18% stretch close to the top, I really think a hub motor at 17a with 100w of rider input would struggle up that.