crossbreak
1 MW
Miles said:
dm9876 said:
Thanks for the links!
low KV motor 1.5KW, cheap and waterproof
- Thread starter crossbreak
- Start date
Thanks for the links!
crossbreak
1 MW
Looks like this topic ran into a dead end :? cause the wind generator turns out to be not very efficient and it's still heavy.
Another source for such a motor would be this one: http://www.monsterscooterparts.com/...tor-11-tooth-8mm-05t-chain-sprocket-1318.html
but there is no info about KV, diameter or length. Looks like a kollmorgan, but it turns out that the picture maybe wrong and it will be discontinued so the seller can't give any info here
looks like we have to kick out one target specification. So i will stick back to the proposal of toolman
which fails at the low KV argument, but it's cheap ($108), lightweight (850g) and short. Maybe the following would be an acceptable compromise:
Running this motor at half of it's rated speed of about 7000rpm would be a compromise. It is 230KV stock, I assume that it's delta wound like all stock rc-outrunners I saw in my live, so we could get it down to 135KV if we redetermine it in WYE (by the proven method lebowski once described). This would lead to round about 3800rpm loaded speed at at 37V and 10s lipo. A three-stage reduction to the crank would be preferable to gain a reduction of around 45:1 to the crank.
Using a 50amps max controller we would scratch along our spec of 1.5kw. A stock KU-123 sensorless controller (cheap to get from bmsbattery) has 30amps max and is able to run even my biggest 80-100 outrunner if the traces are beefed up. It may even handle the 50amps target.
Arguments for this motor are:
-high stator pole count (I have no reference here, but it has definitely more than 12 like the early turnigy 80-85, 80-100 and 63-74 motors)
-thin stator sheets (no reference yet)
-big cooling surface due short stator stack, it should be possible to run it enclosed to make it waterproof (took the spec sheets and diagrams of the CPM-90-22-1500 motor as an analogy http://www.cpmotors.eu/en/downloads/, the controller uses field weakening so the chart is not 100% comparable, i'd like to post the charts here but i'm afraid that would be a copyright violation
)
-could fit between the standard BB width of 68mm, to keep packaging simple (no reference here either, hobbyking states that it has a 40mm can, which is quite promising)
Cons:
-gas engine-style rotor mount
-needs extra housing
-high rpm
I'm thinking of a box that just fits below the frame just like the GNG drive, but completely enclosed and only 68mm wide, the housing is a heatsink for the motor, the whole unit would weight around 3kg (6.6lbs), dimensions ca. 200x 85x 68mm (7.9x 3.4x 2.7 inch)
Another source for such a motor would be this one: http://www.monsterscooterparts.com/...tor-11-tooth-8mm-05t-chain-sprocket-1318.html
but there is no info about KV, diameter or length. Looks like a kollmorgan, but it turns out that the picture maybe wrong and it will be discontinued so the seller can't give any info here
looks like we have to kick out one target specification. So i will stick back to the proposal of toolman
toolman2 said:http://www.hobbyking.com/hobbyking/store/__17986__Turnigy_RotoMax_1_60_Brushless_Outrunner_Motor.html
-not a bad contender? 58mm case length and $108, rated for 2960w at 7000rpm (crap i know), proly better suited to 1kw at 1800rpm rather than 1.5kw, but there are also countless size choices upwards of this one.
- yes it still needs siliconeing up i spose, but hopefully you can see the value in a motor being 3 or 4 times lighter for the same power
or saving 2 or 3kg?
which fails at the low KV argument, but it's cheap ($108), lightweight (850g) and short. Maybe the following would be an acceptable compromise:
Running this motor at half of it's rated speed of about 7000rpm would be a compromise. It is 230KV stock, I assume that it's delta wound like all stock rc-outrunners I saw in my live, so we could get it down to 135KV if we redetermine it in WYE (by the proven method lebowski once described). This would lead to round about 3800rpm loaded speed at at 37V and 10s lipo. A three-stage reduction to the crank would be preferable to gain a reduction of around 45:1 to the crank.
Using a 50amps max controller we would scratch along our spec of 1.5kw. A stock KU-123 sensorless controller (cheap to get from bmsbattery) has 30amps max and is able to run even my biggest 80-100 outrunner if the traces are beefed up. It may even handle the 50amps target.
Arguments for this motor are:
-high stator pole count (I have no reference here, but it has definitely more than 12 like the early turnigy 80-85, 80-100 and 63-74 motors)
-thin stator sheets (no reference yet)
-big cooling surface due short stator stack, it should be possible to run it enclosed to make it waterproof (took the spec sheets and diagrams of the CPM-90-22-1500 motor as an analogy http://www.cpmotors.eu/en/downloads/, the controller uses field weakening so the chart is not 100% comparable, i'd like to post the charts here but i'm afraid that would be a copyright violation
) -could fit between the standard BB width of 68mm, to keep packaging simple (no reference here either, hobbyking states that it has a 40mm can, which is quite promising)
Cons:
-gas engine-style rotor mount
-needs extra housing
-high rpm
I'm thinking of a box that just fits below the frame just like the GNG drive, but completely enclosed and only 68mm wide, the housing is a heatsink for the motor, the whole unit would weight around 3kg (6.6lbs), dimensions ca. 200x 85x 68mm (7.9x 3.4x 2.7 inch)
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Whiplash
1 MW
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- May 10, 2010
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- 2,906
I have already built something like that! LOL! It worked quite well but was noisy so I went to my MAC bottom bracket mount.... I was using an RC motor though so with a lower KV motor it might work great!
http://endless-sphere.com/forums/viewtopic.php?f=28&t=18517&start=675#p466057
http://endless-sphere.com/forums/viewtopic.php?f=28&t=18517&start=675#p466057
crossbreak
1 MW
thx for your post, i see, some aims i want to claim are not with your drive. it's not enclosed (yet?) and has high rpm. i hope i slayed down the issues which disturbed, but what you learned is what i learned, so this is appreciated much if there are things plz post them! I already learned a lot about mounting such drives. like the great pull on the chain which just banded my first mounts 
This drive will be mounted on the right side at the crank. the rest of the load will be taken by frame clamps. I guess this will work after my experiences with the tongxin setup, which did the same chain force.
the 1.5kw are chosen with care, since this is the max what can be done without over stressing bicycle tech IMO. I already use a 53:13T final drive reduction to get rid of some chain force, since my chains don't last long, most times less than 2000km this is just the least common denominator for bycicle-through-the-gears-drives (=middrives). The least i can do is to collect your ideas, fails and successes and spit out something that might be common sense. this might just slay down the needs for an overpowered bicycle, since with this drive, the energy can be used efficiently, but it has more power a battery can spend, worth carrying in a back pack for daily use.
if there are things plz post them! I already learned a lot about mounting such drives. like the great pull on the chain which just banded my first mounts This drive will be mounted on the right side at the crank. the rest of the load will be taken by frame clamps. I guess this will work after my experiences with the tongxin setup, which did the same chain force.the 1.5kw are chosen with care, since this is the max what can be done without over stressing bicycle tech IMO. I already use a 53:13T final drive reduction to get rid of some chain force, since my chains don't last long, most times less than 2000km
this is just the least common denominator for bycicle-through-the-gears-drives (=middrives). The least i can do is to collect your ideas, fails and successes and spit out something that might be common sense. this might just slay down the needs for an overpowered bicycle, since with this drive, the energy can be used efficiently, but it has more power a battery can spend, worth carrying in a back pack for daily use.
bandaro
10 kW
So, a little design I have been working on that seems relevant to this thread, slightly bigger than the one above, but this should work with a 6374 motor, reduction about 40:1 using bike chain to the cranks, or higher with #219. By the looks of things, I may change the design to fit this new motor, if it proves suitable. It is mounted on a giant stp dj style frame, belt primary and spur secondary, fully enclosed in a 3d printed guards. Thoughts?
Not sure if this cheap motor has been overlooked or not.. I mentioning it because a motor can do 1.5x its voltage as a general rule.. Ive read anyways...
$105 - 1000W Motor - 36 Volts 2600 RPM, 40.0 Amp (Style: XYD-14A)
http://tncscooters.com/index.php?route=product/product&path=52_56&product_id=512
this motor is used on my mid-drive... its kinda heavy.. but very sturdy
Although it is not water-proof.. really though these xyd type 3 bolt mount motors are not far from it... I road mine every rainy day to work in Richmond, BC all last winter without issue... I made sure to seal around the cable coming out of the motor can... the twist throttle was the only problem Ive had ... still need to find a twist throttle waterproof solution ???
I use 1/4" chain for the drive... 8T on the motor (coupling).. 80T sprocket on the right side crank... 18T and 38T MTB bike chainrings.. 11-34T rear cassette... and yeah it goes like snot...on just 36v with 1000w controller.. 13-1400w peaks
tomorrow Im switching out the 8T with a 5T sprocket on the motor... however the 5T are just so small they make a great deal of noise... imagine almost like a F1 engine.. I think the ultimate solution is a 7T motor sprocket with dual 17T - 40T MTB chainrings and 48V 1500w controller...
$105 - 1000W Motor - 36 Volts 2600 RPM, 40.0 Amp (Style: XYD-14A)
http://tncscooters.com/index.php?route=product/product&path=52_56&product_id=512
this motor is used on my mid-drive... its kinda heavy.. but very sturdy
Although it is not water-proof.. really though these xyd type 3 bolt mount motors are not far from it... I road mine every rainy day to work in Richmond, BC all last winter without issue... I made sure to seal around the cable coming out of the motor can... the twist throttle was the only problem Ive had ... still need to find a twist throttle waterproof solution ???
I use 1/4" chain for the drive... 8T on the motor (coupling).. 80T sprocket on the right side crank... 18T and 38T MTB bike chainrings.. 11-34T rear cassette... and yeah it goes like snot...on just 36v with 1000w controller.. 13-1400w peaks
tomorrow Im switching out the 8T with a 5T sprocket on the motor... however the 5T are just so small they make a great deal of noise... imagine almost like a F1 engine.. I think the ultimate solution is a 7T motor sprocket with dual 17T - 40T MTB chainrings and 48V 1500w controller...
crossbreak
1 MW
your flux sim is very promising, Miles, thanks for this cross reference!
Nice design, it's also designed to fit between the BB. I like the shape. I'm missing a tensioner for the belt as well as for the crank drive chain. I'm no fan of deflection pulleys like i did with my last drive i prefer the motorcycle style dropout tensioners. You use a single sheet for mounting the drive on the BB and for the bearings/housing. I would split it to be able to move the drive and adjust crank drive chain tension.
I love these carbon/fiber laminated drive covers, as well as printed ones (the look). But it is also some plastic surface that can not cool the motor, that's why I tried to create a completely enclosed design made from alloy.
thanks for the tip, but I gave up on using brushed type motors. The perfect reduction for your motor would be a 23:1 reduction. Using your 80T chainring your sprocket in a single stage drive, the motor sprocket only would have 3 1/2 teeth
I speed variation gets important below 13T sprockets (due the so called polygon effect), that's why they are only used if run very slowly. Also the chain growth of your chain should be monstrous cause you use your #25 outside it's spec. I propose you use a 2 stage setup, like the GNG.It will be more efficient durable and will last triple as long I know this makes your drive more bulky. A 80T to 13T belt reduction using a 10mm HDT-5T belt would be perfect fit for you motor. Or you use the stock 11T #25 sprocket and a 68T as primary reduction and a 13T freewheel to 48T chainring with the normal bike chain for example.
plz be so kind and post the weight of the motor and a cross reference link to your build thread for completeness. The length of the motor (5.25" or 133mm) sadly disqualifies this motor for a middrive setup IMO.
bandaro said:
Nice design, it's also designed to fit between the BB. I like the shape. I'm missing a tensioner for the belt as well as for the crank drive chain. I'm no fan of deflection pulleys
like i did with my last drive i prefer the motorcycle style dropout tensioners. You use a single sheet for mounting the drive on the BB and for the bearings/housing. I would split it to be able to move the drive and adjust crank drive chain tension. I love these carbon/fiber laminated drive covers, as well as printed ones (the look). But it is also some plastic surface that can not cool the motor, that's why I tried to create a completely enclosed design made from alloy.
myzter said:
thanks for the tip, but I gave up on using brushed type motors. The perfect reduction for your motor would be a 23:1 reduction. Using your 80T chainring your sprocket in a single stage drive, the motor sprocket only would have 3 1/2 teeth
I speed variation gets important below 13T sprockets (due the so called polygon effect), that's why they are only used if run very slowly. Also the chain growth of your chain should be monstrous cause you use your #25 outside it's spec. I propose you use a 2 stage setup, like the GNG.It will be more efficient durable and will last triple as long I know this makes your drive more bulky. A 80T to 13T belt reduction using a 10mm HDT-5T belt would be perfect fit for you motor. Or you use the stock 11T #25 sprocket and a 68T as primary reduction and a 13T freewheel to 48T chainring with the normal bike chain for example. plz be so kind and post the weight of the motor and a cross reference link to your build thread for completeness. The length of the motor (5.25" or 133mm) sadly disqualifies this motor for a middrive setup IMO.