Low KV Q128H at ridiculously high voltage? Which one (Alps)?

fellow

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Sweden, EU.
Mac 12T is too heavy for my new full suspension project, so I have some thoughts about Q128H. I'm building my battery myself so I'm not limited up to about 100V, but not lower than 67V. To make this task more interesting, I've limited myself to max 17A to play with, preferably less.

Speed is not the goal, I already crap my pants at 20mph(32Km/h). :shock: I would prefer that it revs ridiculously high whyle climbing slow, to keep the mass and size on the low side. It will be oil cooled, maybe even externaly later on. In essence, I'm looking for a hub that is a light sub 3Kg RC motor wannabe.

The question is, does 48V 201 rpm Q128H have same 13.2:1 reduction as 36V 201rpm version? Or they just use lower gear reduction ratio and windings instead? Are those gears interchangeable? Any other gearsets that can increase this 13.2:1 ratio? My summerhouse is at the top of the mountain that look something like this, and I really hate pedaling. Or shall I choose the xiongda 2 speed and use it in 1 speed only?
wurzenpa%C3%9F.jpg

KORENSKO%20SEDLO77.GIF

foto2.jpg


Does 48V version Q128H use this (like Q128H 36V does):
1H1JTF_UWU17.jpg

or this(as the old Q128 does)?
1MMSHU_K0CXY.jpg


Is this correct?
Reduction ratio: 13.2
Power: 800W
Nominal Voltage: 48V
Hall Sensor: Waterproof hall sensor connector
Dropouts 145mm (135mm as a single speed??)
Cable Location: Left
Brake Type: Disc Brake, V-brake compatiable
Rotor alnico number: 16
Weight: 3Kg
 
Too bad the old Ecitypower site has been deactivated, it had the info you are looking for.
I think your idea is a dead end.
Take the Cute for example.
The reduction on the 201(standard) is 1:16, the lowest of any of the variants.
Even that wouldn't be low enough to off-sett the high Voltage and keep you in a hill climbing speed.
Then there is the issues of trying to run 67V thru the Q128.
As I recall, Mkeefer started frying MXUS geared minis around 16S.
For the Money it would take to up-grade the controller, wiring, charging, etc. for big Voltage, you could do a 2WD.
Maybe two Q128H's on 48V. The frt. mount Q128 has 100 mm dropout width.
It would be faster than the 2-speed stuck in low gear.
 
I talked to bmsbattery about this motor as i was interested in it..
The 142-145mm width can unfortunately not be achieved by anything other than modification of the axles with expensive machinery.. they say that it is not possible to change things by removing bolts etc.

I tried to get them to do a proper higher speed winding, but they refused to do it..

Also, they revised their power output graph.. it it not an efficient geared hub at all.. while it's power output per weight is fantastic, i can't recommend it.
 
Thank you both for your answers, it really means much as I'm compleatly lost which motor to choose. The motor is meant for this project, it's very high-tech with "invisible batteries", no budget-limit one http://endless-sphere.com/forums/viewtopic.php?f=6&t=68305&p=1029527#p1029527. What motor do you recommend for this one? I can choose between 16s, 18s and 24s voltages. I have only place to hide one 95mm controller, which limits me to only one 6-fet controller, thus limiting the current.
file.php
 
For climbing grades up to 32%....
..you want the most powerful mid drive kit you could possibly buy.

Which would probably be a lightningrods kit.

A bafang BBS02 would probably melt or stall. Unless you have ULTRA TALL gearing where you could climb up that 32% at like.. 5kmhr.. :)
 
I was even thinking of smal high revving Rc motor placed close to the BB and a double chain. I prefer single speed idea, and gearing via the high volts and a big reduction ratio and not distinctive geras. I hate big torky slow rpm 13kg motors, it feels like 1880's. Actually I've always prefered Hondas high revving D16/B16/K20 engines vs Porche/PSA V6 torky dull engines. They have the power, but lack the soul. By the way, Q100H 36V 201rpm have fantastic high rpm techy sound, sometimes it really make me smile .:D
 
fellow said:
I was even thinking of smal high revving Rc motor placed close to the BB and a double chain. I prefer single speed idea, and gearing via the high volts and a big reduction ratio and not distinctive geras. I hate big torky slow rpm 13kg motors, it feels like 1880's. Actually I've always prefered Hondas high revving D16/B16/K20 engines vs Porche/PSA V6 torky dull engines. They have the power, but lack the soul. By the way, Q100H 36V 201rpm have fantastic high rpm techy sound, sometimes it really make me smile .:D


The first >28-ish years of my life I was also focused almost exclusively on very high RPM very high specific power density engines (I wanted to be a F1 engine designer at the time). I went from 4ag's spinning >10,000rpm to B16A's making a lot more power at a lower RPM, to B18C's, to B20's with B16A heads, then K20A, and finally K24A (every time making faster more reliable cars that are better to drive and have lower RPM engines) with supercharger and nitrous before I finally just gave all my gas stuff away due to a complete lack of interest.

In electric motors I took a similar path, first build was dual 10,000rpm RC motors, next build was Agni95R and then Perm132 and MARS 0913 and both the 5kW and 10kW golden motors, and finally ended up with the lowest RPM motor of the bunch, that provides more power everywhere in the powerband than I know what to do with.

I didn't expect to be into lower RPM higher torque motors, it's just what survived the racing and what delivered the performance. Everytime I took the step to move to a slower turning higher torque motor, it improved everything about the vehicle, both in my ICE experience and Ebike experience, and this is coming from someone who spent the majority of their life obsessed with how to design for maximum RPM.
 
Thermal mass matters a lot.
RC drives are fantastic, but can only shed so much continuous waste heat. It all depends on whether you're willing to find the motor's limits and work with them or not. The smaller the motor, the more overrated it seems to be.. yeah.

It's a real interesting engineering game, all of this.. :)

I still think that a multi-geared system would be idea. What will pull you up the hill at a freaking 32% grade will be hilariously slow on the flats.

I'd try the lightningrod's kit first... coupled with the most broad gearing range you could possibly manage.
 
Life: I understand that big motors do improove things a lot. My problem is that I have total mass goal of 25kg for the complete downhill ebike, I simply can't have half of that in a motor. My last ebike have total mass under 17kg, it's lighter than most of the cheap normal bikes sold in a nearby store. I simply don't have need for a high speed or wheelies (I guess I'm getting old), I just need a good light power dense slow climber. As for a Honda, I've been part of a Honda Performance Club in Sweden at the end of the 1990-s, those were the days:).

Neptronix: Are there any small oil cooled RC motors with external oil cooler pipes? That could solve a thermal mass problem, and visible oil cooler would look very interesting on a downhill bike with no visible batteries or controller...
 
I run a low RPM 36V BPM in a Fighter with a small Lipo pack (20S 1P 8000mah). Has a usable 500Wh capacity. At 85V hot off the charger, I think you can consider it to be well and truly overvolted.

Fighter Frame is not much different in weight to a DH bike. Probably 1 kG in it. This motor has twice the mass of the motor you are looking at and although it does most things really well, I couldn't see my setup climbing the hills you are proposing and to last too long.

However,my BBS02 equipped Free Ride bike with its 500Whr 18650 pack, 44tooth Chainring and 11-34 tooth cluster would have a very good chance at doing this. Just need to be sensible with the level of assist and put in a reasonable bit of pedaling effort. Ideally an aftermarket 42 tooth with the proper offset and 44 tooth mega gear on the back, and it would do this climb no problems.

However, as you need a 68mm to 73mm BB I doubt that nice looking frame of yours will fit the bill.

Edit: Just done a quick search on the frame. Looks like it does have a 73mm BB. 8)
 
No that I know of. If you go down the path of Cyclone or GNG, I think they have isis options that do you can fit a decent crank. The BBS is square taper. Not very sexy but I have never had any issues with it. Never bent a crank even when the bike has been dropped.
 
I bought a Q128H with hopes of running 72V. Unfortunately, the Q128h is made with 0.5mm laminations so it would likely be very inefficient even if the motor could survive those high RPMs. According to BMSBattery's test data, the Q128H is good for 57 Nm at 70% efficiency. Use a mid drive or 2x Q128H like Motomech suggested.

Use this calculator here and look at traction force:
http://www.mne.psu.edu/simpson/courses/me240/bikecalc1.htm

114+ N m will get a 180lb rider and 45lb bike up a 30% grade without pedaling.
 
Kepler: I've seen those, I would prefer something sexy to compensate for my aging wife*lol*. I think I would choose the hub and simply push the thing uphill, and wait for the chinease folks to make something better...

Jasonv8z: 0.5mm lamination thickness is dissapointing. Is your Q128H 48V or 36V version? 114NM is just the info I needed, thanks.

How does the mac 12T perform (in Nm anyone?), the new ones are 0.3mm lamination? On the bad side, Mac 12T is almost 5 kg. Someone said that they are not very suitable for full suspension setup because of that.
 
I've gotta couple 201RPM Q128H, 700c wheels running 16S RC Lipo (59-67V). Top speed about 22-24MPH off the charger. I dunno anything about laminations or efficiency ratings but they climb like mad on 900W peak controller power. In service for nearly a year - windings and gears look fresh as day 1.

Reason for disassembly - clutches have been sorta PITA eating springs which supposedly help rollers (pawls) engage clutch drum. One motor I left the springs out and it's been fine with only an occasional slippage on start-up. The other clutch I sourced some much thicker wire springs which seem to be holding up just fine so far.

Based on what I've seen/experienced, I wouldn't hesitate to push Q128H up to 72V. They're an ok little motor IMO and one of the easiest mini-motors to disassemble I've had the pleasure of yanking apart.
 
Ykick: Just to be sure before deciding/ordering, yours is 48V version 201rpm? I've read about the clutch problems you had. I'm sucessfully using ATF oil on its younger brother Q100H 36V 201rpm, never had any problems. Maybe ATF is the cure for your Q128H too? Or is it simply the bad material choice, so it wears out because of the force and not the temperature/lubricating?

By the way, will it fit in a 135mm frame as a single speed? I cant spread it more. How many gears are the max when disc is used in 135mm frame? Is the internal gear ratio 1:13 on yours, or just a simple one way reduction 1:8 as the Mac and other low internal rpm ones got?
 
Problem with the clutch springs seemed to be the spring wire is/was very thin and kinda soft which kept getting caught under the rollers, jamming up the clutch. As mentioned I’m running one without any springs, light oil and the other I found some heavier gauge and harder wire springs which seem to be holding up so far.

These motors were ordered as 48V, sorry I never counted gear teeth but I do recall 2 stage reduction.

As far as fitting into frames - playing around with spacers/washers/nuts I manage to fit them into 135mm dropouts requiring little to no spreading.

As you can see in this photo using a 5 speed freewheel it’s almost exactly 135mm:
IMG_0038.JPG
As you can see, offset spoke heads to help dish the rim to the hub. Lace my own wheels using 13/14 butted spokes.

The other Q128H bike uses 7 speed freewheel and needed to be spread a little more (138mm?) when assembling.

That one's a co-workers ride now so I don’t have it handy to measure but he rides it hard and all winter, racking up lotsa serious, messy miles. Sorry, no disc brake installations to share.
 
Thank you, your information about double stage gearing and 48V is very helpfull. I think I'll go the same route as you but starting with 75.6V and 8A continuous(=16A peak), keeping it at 600W continuous (=1.2Kw peak) ATF oil cooled. That should be enough for top speed of 40km/h (=25 mph) HOTC, if those 600W continuous are enough to fight the wind resistance. I guess it is not wise to ask more from a 3 kg motor?
 
Just a couple notes to add - I do use a Lyen sensored 6FET controller, smooth, programmable operation. Sensorless reportedly do not work and electrical RPM I can see why.

2 spacers over the axle inside freewheel so single cog might not need both of 'em? That might shave down another 20mm width if you have the dish for it?

I've been pleasantly surprised by the little guy and it's willingness to handle rated power with no signs of burnt windings or melted gears to date.
 
I suppose i have to repeat myself.. any hub motor at a 32% grade is going to melt, no matter how good or well designed the hub.

Here's a highly efficient geared hub doing a 20% grade on ebikes.ca's simulator.
http://www.ebikes.ca/tools/simulator.html
Overheat in 13 seconds.
 

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I was under the impression OP had resigned themselves to pushing/walking steepest portions?
 
I must have missed that... my bad :oops:

Still gonna melt up a 10% grade though.. how much of that do you have to conquer?
 
I have the 36V 201 RPM version. It also needs 145mm spacing between the dropouts unless you want to remove some material away from the axle to make it fit.
Does anyone know who makes these Cute brand motors? I wish we could order a faster wind Q128H with thinner laminations.
 
Neptronix: It's about 400m (1/4 mile) of climbing, worst part. Altitude difference maybe 40 to 80m, but it's not constant grade - goes up and down. Takes about 7 minutes to walk/push the bike every time i visit the local village. The rest is managable.

That's my summerplace. The Wurz pass/Korensko sedlo is the place that I often visit, it's ideal for "Pikes Peak" - like race as the road is wide and unused and connects 2 EU countries so no passport is needed. There is a motorway tunnel some 10km long so no one uses the old historic road. The downhill on the other side is as brutal as the upphill, car brakes easily overheat here as the downhill "never ends". You simply can't pick up the speed because you can't stop later on-even racing dot fluid boils here if yiu are not carefull. A lot of warning signs makes it ideal youtube background. http://en.m.wikipedia.org/wiki/Wurzen_Pass

The fun part is that i can't find a test hill here in Sweden, where I normally live. Everything is totally flat...

Jason: I believe http://www.aikema.com.cn/ is their webpage, but I'm not 100% sure as there were no markings on my old q100h hub. Here it says "reduction ratio 9.6", which corresponds badly to bmsfactory 13:1.
2013622151859388.jpg


Q100H seems to be the rev king at 12.6:1, according to aikema:
201362215610507.jpg


Ananda is another intetesting site, one of their motors looks like specialized turbo motor:
http://www.ananda.com.cn/
 
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