QS205 V3 - Longevity?

[C158]

How many miles/hours should one of these motors last before it would need to get replaced? I've seen somewhere QS states 3 to 5(?) years? But no conditions around that. Are these motors meant to be used a fair amount?

I understand there could be many factors that play in....but just assume normal commuting from light to no throttle to full out WOT. But not torturing it endlessly.

Thank you

 

[MadRhino]

I am pretty hard with them. I’ve had 3, of which 2 are still riding. The one that is dead had 35000 km, and could have been saved if I had not postponed bearing replacement. I feed them up to 25kw in acceleration busts, but I never let them overheat. All of them had been on fast ebikes, 100+ kmh. One is still on my street commuter, had done some 20000 km already, riding hard and fast on 24s RC lipo that I replace with fresh bricks every year to keep max power.

Like any hub motor, the main factor of longevity is temperature. Then, don’t let the bearings wear until the stator has a play, for rubbing the windings against the casing is sure death for a motor.

 

[amberwolf]

If you're not torturing it, any DD hubmotor should last essentially forever, as long as the bearings are lubricated and don't wear out (or you are willing to pop the covers off and replace them wehn they do; it's usually easy).

There are no moving parts inside the motor to wear out, except for those bearings.

If you're riding on salted roads or other places where water and corrosive stuff is going to get in the motor (and no, you can't really completely seal one perfectly), then it depends on how fast it corrodes, for how long it will last. You can open it up when you get it and treat it with stuff to help prevent such corrosion (see the various rust / repair / restoration threads), and depending on it's design there may be stuff you can do to seal it better than factory, but it still wont' be a perfect seal or preventive.


The only other gotcha is you must use correct mounting of the axles, so that the flats are fully engaged and clamped tightly, especially if you are using regen braking, which will cause rocking of the axle back and forth.

If you don't mount it well, you could shear off the axles, and that could happen quickly or slowly, depending on too many things for me to predict.

 

[C158]

Thank you for the replies. Mine is in a Q140MD and have been commuting with it. Currently have 3,000 miles on it and it got me thinking. I don't feel like spending another $600(?) with Qulbix so soon to buy a new motor. Ha! I live in the Pacific Northwest. The roads can be a bit shitty, but other than that I think the bike has a fairly easy life. Its certainly not used and abused like they market them to be. Just WOT on roads when I can.

Motor temp gets to 120C at times in the Summer, but it never turns off. Riding around yesterday the tmp got to 100C for a bit before coming down. Pretty sure this is NOT what you guys mean by overheating though. Its programmed to stop working before overheating anyways - and ive never gotten it there. Also, taking the motor apart would be a pretty big PIA, so would just likely run it into the ground unless there were some clear signs (noises) that would prompt one to want to check the innards out. This isnt the easiest thing to do "just to check the motor" with the way the bike is setup. So if it was destroying itself and not making any funny noises I would likely never know until it just stopped all together.

 

[MadRhino]

So, your hub motor is mounted as a mid drive?
It is likely to last without problems for very long since it does have a temp sensor and heat protection set in the controller. 120C is not hot, barely warm. 150C is safe. 180C is where danger begins. A mid mount motor is not as obvious as in-wheel when bearings are worn out, so checking this should be on your maintenance schedule twice a year. Excessive chain tension could wear the motor bearings faster. Drive train maintenance should be your priority, once a week if you ride dirty.

 

[C158]

Thank you. Yes, it is mid-mounted. Good to know on the temps. I've never got it over 120 to 126C and even then very rare. I will have to learn how to check the bearings. Will try to do so end of this Summer. Its a huge pain for me to do though on that bike as I do not have a stand.

I check the chain tension every time I ride. I am pretty sure I am doing it the right way, but if you have any tip I would appreciate it. The bike is not ridden off-road, but does get dirty as I use a very liberal amount of dry lube every other time I ride (usually my rides are +- 50 miles) The bike gets washed every other ride.

 

[MadRhino]

I am used to do the maintenance on my bikes upside down, but it is easy to make a service stand with scrap square tubing, even a plastic milk box could do.

Seems to me that your bike is underused. I mean, it is like buying a motocross to ride the streets. At least, limit the suspension travel, set it stiffer, and buy some street tires. It will help making it a better street ride.

 

[DogDipstick]

Are we talking until the first failure from new? Or are we talking irreparable?

I got a little 35H 205 V1 and it lasted 720~ miles under some good torture. +150C temps > 50% of the time. Hall failed.

Slapped a new set in, away we go. Repairable. So 700mi~ @ about Rollback set <150*C. Hard cut at 190*C Halls limit was somewhere round 150* C. I think. The halls the hub came with.

I have seen pics ( IDK wut yall do to get them that way) that look like burnt charcoal. No fixxing that. Since, i have lowered both the rollback and hard cut.

 

[MadRhino]

Are we talking until the first failure from new? Or are we talking irreparable?

I got a little 35H 205 V1 and it lasted 720~ miles under some good torture. +150C temps > 50% of the time. Hall failed.

Slapped a new set in, away we go. Repairable. So 700mi~ @ about Rollback set <150*C. Hard cut at 190*C Halls limit was somewhere round 150* C. I think. The halls the hub came with.

I have seen pics ( IDK wut yall do to get them that way) that look like burnt charcoal. No fixxing that. Since, i have lowered both the rollback and hard cut.

Yeah, but we are talking about the QS205H50v3, that is another animal. Much like to compare a dog and a horse.

 

[amberwolf]

I got a little 35H 205 V1 and it lasted 720~ miles under some good torture. +150C temps > 50% of the time. Hall failed.

No surprise, as the common halls used in hubmotors are assorted "clone" parts that it is difficult (at best) to find specs for, and no way to know what, if any, qc is actually done on them to verify they match those specs. So basically no way (other than destructive testing by the end-user) to know for sure what the temperature (or other) limits are for the parts typically supplied inside the motors. :/

But even if they were, for instance, genuine Honeywell parts, 150C is the *limit* of operation of the usual types used in motors, and some of them only go to 125C. So operating above that limit, at all, for any amount of time, may damage or destroy them (though it is unlikely it would be an instant failure, more like accumulated damage over time, worse the higher the temperature excursion).

Yeah, but we are talking about the QS205H50v3, that is another animal. Much like to compare a dog and a horse.

Not as far as the halls used inside, or the temperature limits of those parts. That would be the same for any halls in any motor (that uses the same halls).

 

[DogDipstick]

Are we talking until the first failure from new? Or are we talking irreparable?

I got a little 35H 205 V1 and it lasted 720~ miles under some good torture. +150C temps > 50% of the time. Hall failed.

Slapped a new set in, away we go. Repairable. So 700mi~ @ about Rollback set <150*C. Hard cut at 190*C Halls limit was somewhere round 150* C. I think. The halls the hub came with.

I have seen pics ( IDK wut yall do to get them that way) that look like burnt charcoal. No fixxing that. Since, i have lowered both the rollback and hard cut.

Yeah, but we are talking about the QS205H50v3, that is another animal. Much like to compare a dog and a horse.

Is it? Same magnet composition and same factory, I was presuming.. same connectors save the big ones, same pvc insulation... , and same shape and size,,... same thermister.. same hall sensors that they have in the stock at the moment, same font on the hub... Copper and enamel, probally came off the same roll... the spacers and stator insulation from the same supplier...

yeah alu core and extra 15mm depth.. but .. much more similar ( to each other, the QS205V1 and the V3) than a Crystalyte from Grin or a BMC or many of the generic something like that...

Been studying different manuf styles... as of late. I honestly shove 8Kw in and get 3.8Hp out. My lil V1. I know that isnt "QS 3KW" numbers.. but .. the over volting and heat are similar..

Yes I know the diff... but in my simple juvinile mind I figured they were somewhat similar, comming from the same horse-dog, or dog-horse, or whatever you called it...

with all the experience you have... Thanks for the correction I would never get over my newbness without ya....


Duh. Lol . What a dumb animal this dog is. Honestly I have seen horses scoff at dogs. Now I know why. Ty.

Fact is I had a 2018 hub, bought new, under the QS label, and figured Id abuse it till something broke. Well, Im here to tell you what did, the Halls... in 720 miles of over 150* over 50% of the time.. .

Or do they have different Halls? Different Magnet composition? Different bearings? different glue? Different Thermistor ad all that different everything? LOL I honestly doubt it, but correct me if the only differences are NOT primarily the magnet depth and the core composition.... please. I presumed that was pretty much it.


LOL same friggin axle from the looks of it... but this newb aint for sure. Same little shitty tq plates and double nut. Same bearings.

Thanks so much for the correction, Rhino. Dont know what I would do without ya.

No, they were not Honeywells but yea from the data I found they were rated to the 150* i think.

Rhino? Have you had both? Both the Horse, and the Dog, models of this animal (motor)?

I assure you I will.
If you dont know Ill find out then but thats kinda why Im here makin a tizzy too.
I want to know. What did you see different? ( aside fromt he obvious... 35H vs 50H, and the core compositions.. 2 sets of sensorbanks) ( like sensor, magnet ,bearing, axles? different? I implore... )?

Looks like a Doghorse to me, and or a Horsedog. If you ask me.

 

[DogDipstick]

Have you had both? Both the Horse, and the Dog, models of this animal (motor)? I assure you I will. If you dont know Ill find out then but thats kinda why Im here makin a tizzy too. I want to know. What did you see different? ( aside fromt he obvious... 35H vs 50H, and the core compositions.. 2 sets of sensorbanks) ( like sensor, magnet ,bearing, axles? different?)?

Looks like a Doghorse to me, and or a Horsedog. If you ask me.

 

[MadRhino]

Are we talking until the first failure from new? Or are we talking irreparable?

I got a little 35H 205 V1 and it lasted 720~ miles under some good torture. +150C temps > 50% of the time. Hall failed.

Slapped a new set in, away we go. Repairable. So 700mi~ @ about Rollback set <150*C. Hard cut at 190*C Halls limit was somewhere round 150* C. I think. The halls the hub came with.

I have seen pics ( IDK wut yall do to get them that way) that look like burnt charcoal. No fixxing that. Since, i have lowered both the rollback and hard cut.

Yeah, but we are talking about the QS205H50v3, that is another animal. Much like to compare a dog and a horse.

Is it?
...
Duh. Lol . What a dumb animal this dog is.
...
Thanks so much for the correction, Rhino. Dont know what I would do without ya.

The bigger the motor, the bigger the magnets, the more copper, the less it is likely to overheat, and the shorter the time it is likely to stay hot when it does happen.

Simple as that. Like a horse carrying you all day, or a dog exhausted after 5 minutes, even if both are made with the same flesh and bones.

Sorry that you interpreted this personnal. I can’t do anything about that.

 

[DogDipstick]

Simple as that. Like a horse carrying you all day, or a dog exhausted after 5 minutes, even if both are made with the same flesh and bones.

Sorry that you interpreted this personnal. I can’t do anything about that.

Ty, I understand, nothing personal. Thats a good example above. ( horse laboring or dog... carrying its weight.. ) So you have had both? You know there is a big difference? I have seen the data graphs, and read the results from people for about year now... and doesn't seem much different. My motor still make 100Ftlb or more, unlike alot of the other lesser generic ones yall spent years with.

I would liken it to a Quarterhorse ( faster lighter hotter shorter) vs a Thoroughbred ( slower cause of more mass to move but faster in the long run, cooler), I used that euphemism once. Both look like horses. When you say one looks like a dog and the other looks like a horse, well I see different.

Bearing life should be comparable. And sensor life. Looking at runnning temps only, not outputs or inputs. Go over 50% time over 150*c and you get about 5 months. Thats at about 125miles a month for me personally, or 70 cycles of my battery, and around 100Kwh throughput.

You know, if your big horse has 1000lb on it.. it still getting hot.. and a small horse with 500lbs still gets just as hot ... and a hose can cool off a horse pretty good... Unless you are an appropriately wound horse for the wheel dia you are pulling and the KV and all that.. then you dont get hot and cam make more.. horsepower... lol....

I mean, I have seen steel core 40H "3kw horses". I would think my "QS Store "V1 is much more similar to the V3, in bearing life, and sensor life, and winding design ( durability) than the random steel core 40H magnet "3KW " .. er.. generic "dollar store" horse.

 

[MadRhino]

Simple as that. Like a horse carrying you all day, or a dog exhausted after 5 minutes, even if both are made with the same flesh and bones.

Sorry that you interpreted this personnal. I can’t do anything about that.

Ty, I understand, nothing personal. Thats a good example above. ( horse laboring or dog... carrying its weight.. ) So you have had both? You know there is a big difference? I have seen the data graphs, and read the results from people for about year now... and doesn't seem much different. My motor still make 100Ftlb or more, unlike alot of the other lesser generic ones yall spent years with.

I would liken it to a Quarterhorse ( faster lighter hotter shorter) vs a Thoroughbred ( slower cause of more mass to move but faster in the long run, cooler), I used that euphemism once. Both look like horses. When you say one looks like a dog and the other looks like a horse, well I see different.

Bearing life should be comparable. And sensor life. Looking at runnning temps only, not outputs or inputs. Go over 50% time over 150*c and you get about 5 months. Thats at about 125miles a month for me personally, or 70 cycles of my battery, and around 100Kwh throughput.

I have filled a full garbage can with fried motors, and busted 2 dozen controllers, in the first years building ebikes.

Enough to know that size does matter, and that identical things made in China are not born equal. Of two exactly the same, one might outlast the other 10, even 20 times the life and abuse.

 

[DogDipstick]

I have filled a full garbage can with fried motors, and busted 2 dozen controllers, in the first years building ebikes.

Enough to know that size does matter, and that identical things made in China are not born equal. Of two exactly the same, one might outlast the other 10, even 20 times the life and abuse.

I believe you, Ty.

Can I have a fried motor? Huhhuhuh? PLS? lol. I only got one, and its not fried.


The last sentence of your last post is interesting, when looking for ( at ) reliability, reproducibility, and repeatability, my 3 favorite things.

 

[MadRhino]

Well, building a lot and solving problems...
I progressively found what is best to use, to build a bike that won’t have problems, can stand the abuse riding hard and fast, can survive multiple crashes... and easy to maintain. Try and error, no science in that, only lots of work and cash invested to get there. And, I am not the kind who likes building. I am a rider first, and build only to fulfill my requirements.

 

[DogDipstick]

So I guess the question is how hard do you have to push a (typical) QS V3 to go over 150*C and invoke damage? hard to answer and apply to any one personal setup, and how it reacts to the input heat. What else causes damage?


So in conclusion:
If you dont push them over 3kw ( ever) will they last forever ( never go over that 150* Hall failure temp)? I couldnt imagine that being any fun, but it would be economical.

I want to know..... cause my plans often include throwing 8x the power in bursts and 3-4x the rated power continuous at the hub I plan to buy... NOT sitting there at the rated (3Kw)power. I want to know how long it will last, also, at this level ( given the ability to exceed the 150* number, at will... and the more the power, the more the braggingpoints, cause more power = cooler than Coolio). The way I look is to see how long I go over a certain threshold ( of temp) ..

 

[C158]

Interesting reading through this....

Some of this is way way WAY over my head as it appears you guys are both builders with bounds of knowledge and tbh I am just a end user who liked the idea of riding this to work and around town along with some off read tracks here and there. Just the fact of my usage.

Ya, I am under using it. I did all the research I could and it was the best thing I could find that was turn-key. Eventually I might get more off-road with it as I plan to buy a vehicle soon that can trailer it to some desired "off the beaten path" locations.

All I am trying to figure out is if I am going to destroy it by my commute, which sees prob an average temp of 75C (maybe 80C) with periods of WOT and most periods of just cruising as I am riding around in the city. It sounds like with it being a mid (less torture vs mounted on the rear wheel), temp cutoff well before it overheating, me not getting it close to that cut off 90% of my riding and overall just being "easy" by what sounds like everyones opinion on it I should be good for quite some time.

 

[MadRhino]

Interesting reading through this....

Some of this is way way WAY over my head as it appears you guys are both builders with bounds of knowledge and tbh I am just a end user who liked the idea of riding this to work and around town along with some off read tracks here and there. Just the fact of my usage.

Ya, I am under using it. I did all the research I could and it was the best thing I could find that was turn-key. Eventually I might get more off-road with it as I plan to buy a vehicle soon that can trailer it to some desired "off the beaten path" locations.

All I am trying to figure out is if I am going to destroy it by my commute, which sees prob an average temp of 75C (maybe 80C) with periods of WOT and most periods of just cruising as I am riding around in the city. It sounds like with it being a mid (less torture vs mounted on the rear wheel), temp cutoff well before it overheating, me not getting it close to that cut off 90% of my riding and overall just being "easy" by what sounds like everyones opinion on it I should be good for quite some time.

The motor is certainly not something you should worry about. The bike that you have is almost on a day off, the way you are using it.

 

[MadRhino]

So I guess the question is how hard do you have to push a (typical) QS V3 to go over 150*C and invoke damage? hard to answer and apply to any one personal setup, and how it reacts to the input heat. What else causes damage?


So in conclusion:
If you dont push them over 3kw ( ever) will they last forever ( never go over that 150* Hall failure temp)? I couldnt imagine that being any fun, but it would be economical.

I want to know..... cause my plans often include throwing 8x the power in bursts and 3-4x the rated power continuous at the hub I plan to buy... NOT sitting there at the rated (3Kw)power. I want to know how long it will last, also, at this level ( given the ability to exceed the 150* number, at will... and the more the power, the more the braggingpoints, cause more power = cooler than Coolio). The way I look is to see how long I go over a certain threshold ( of temp) ..

You can feed very high power before a qs205h50v3 does reach saturation, that would fry it instantly. 25kw is safe, only the time that you feed that power is relevant. That is why monitoring heat is a must when you ride performance.

Continuous power is another story. A motor rated 3kw continuous can’t take much more. Of course that continuous rating had been measured on a test bench, and riding is another situation because air flow does cool it. Yet, air flow cooling is not giving a huge advantage, thus a continuous 4kw would fry it sooner or later, according to load and resistance factors. Still, you need a lot of resistance to make a motor pull 4 kw continuously. Climbing 250 lbs a 15% slope at 40 mph does not reach that continuous power level, so you could do it until your battery is depleted without any risk of overheating. Climbing the same slope at 8 mph would not be safe to do continuously. You can climb as steep as you can stand riding, but you need to do it fast.

 

[Dauntless]

Someone should say specifically HOW to maintain the bearings on those. Is it a simple repack maybe yearly? Is a repack simple at all?

 

[MadRhino]

Someone should say specifically HOW to maintain the bearings on those. Is it a simple repack maybe yearly? Is a repack simple at all?

No maintenance

When they start to have some play: the axle tight in the dropouts, you can easily move the wheel from side to side about 1/8’’. They could last many years. Likely to happen between 10000 - 20000 km.

How: remove cover, press bearing out (can be hammered out with a punch), press a new one (no hammering). Repeat on the other side/cover