5kw hub motor that will take a 6 speed cassette?

[matthillster]

Hi everyone,

I planning a high power ebike build using an enduro frame which I plan to get registered as a moped and use for my 30 mile commute. I'm in the process of getting the parts together.

I understand the qs v3 hub motor is considered one of the better ones the only drawback seems to be that it will only take a single speed gear on the back. Ideally I'd like to put a six speed super range cassette on the back so that if it breaks down I can at least move the thing with the pedals.

I'm going to put a schlumpf drive on the front so I've got a high enough gear ratio so that I can still pedal when it's going pretty fast.

Can anyone recommend a hub motor which has space for a cassette? Or am I wrong about the qs motor?

Thanks!

 

[markz]

Most hub motors take a freewheel, some have cassette option like BMS Battery.

Also, the 5kw Mxus hub is wider then a normal rear dropout widths. I forget the # but QS maybe in same boat.

 

[amberwolf]

Ideally I'd like to put a six speed super range cassette

cassette (goes onto a splined freehub in the wheel), or freewheel (threads onto the hub)?

there are still very few cassette hubmotors; almost all are only threaded for a freewheel.

 

[markz]

Cassette
Bafang BPM2 Rear Hub Motor
Bafang 48V500W CST Rear
Q128C-135mm 500W CST Rear
Q100C CST 36V350W
Bafang MG310 145mm dropout
Nine Continent Rear Cassette Motor, RH212 - https://www.ebikes.ca/shop/electric-bicycle-parts/motors/rear/rh212-std.html
mxus https://www.ebikes.ca/shop/electric-bicycle-parts/motors/rear/mx3005rc.html
eZee V2 (350RPM) Rear Unlaced Hub Motor, New Cassette Freehub Version - https://www.ebikes.ca/shop/electric-bicycle-parts/motors/rear/mezee350rc.html

Though the search from failed info posted.
https://endless-sphere.com/forums/viewtopic.php?f=3&t=94668&p=1387390&hilit=hub+cassette+cst#p1387940
ezee ???

do triple check

 

[matthillster]

Maybe I'm not using the correct terminology. I don't really mind if I have to fit a freewheel to the bike. My main aim is to have more than a single speed on the back. It seems like with the qs motor there's only enough room for one gear.

quote=amberwolf post_id=1533155 time=1582955537 user_id=13812]

Ideally I'd like to put a six speed super range cassette

cassette (goes onto a splined freehub in the wheel), or freewheel (threads onto the hub)?

there are still very few cassette hubmotors; almost all are only threaded for a freewheel.
[/quote]

 

[john61ct]

All the hubmotors listed here as accepting a cassette are DD?

So we're talking about the human power only being geared?

The thought of a geared hubmotor also having external gearing applied, makes my head hurt, but is that also a possibility?

 

[spinningmagnets]

As you seem to already know, 5000W hubs are wide, and are typically sized to allow a single-speed freewheel to fit on a standard bike frame. To fit a 6-speed, the point of attachment 9drop-outs) must be moved outwards. You will also need two strong torque-arms. I recommend custom torque-arms that perform both functions, something like the ones in this pic below, made from steel (water-jet or laser-cut?)

 

[DogDipstick]

Great question.

Still looking for the highest power cassete hub. All those mentioned are low power? I want to retain cassette or FW too...

I guess its the MXUS 45mm DD? the biggest that does a 135mm and has a cassette? I mean, I run the QS V1 kinda hard but I know i need more. 3Kw contin is no prob for my motor but I need something that can take 8Kw+ without overheating. ... So whats the hub for the win here?

 

[matthillster]

Yes I just want a better selection of gears for pedalling.

I realise that when you get to a heavy 5kw bike, pedalling isn't contributing that much but I'd like to be able to pedal to keep fit and stay warm in winter. Also I'm thinking with the option of a large sprocket on the back if the electronics break down I'll at least be able to move it with the pedals.

All the hubmotors listed here as accepting a cassette are DD?

So we're talking about the human power only being geared?

The thought of a geared hubmotor also having external gearing applied, makes my head hurt, but is that also a possibility?

 

[matthillster]

So just bend the frame out a bit so it can fit in a larger freewheel? Won't there be a danger of the wheel axel being too short if I do that?

As you seem to already know, 5000W hubs are wide, and are typically sized to allow a single-speed freewheel to fit on a standard bike frame. To fit a 6-speed, the point of attachment 9drop-outs) must be moved outwards. You will also need two strong torque-arms. I recommend custom torque-arms that perform both functions, something like the ones in this pic below, made from steel (water-jet or laser-cut?)

 

[spinningmagnets]

Here's a second option, which I am surprised more builders dont use. There are many frames with a 2-speed or 3-speed shifter on the front chainrings.

I recall Barent Hoffman did this with a 3000W hubmotor. The rear axle had a single-speed freewheel, and the bottom bracket (by the pedals) had a 3-speed derailleur.

With a high-speed hubmotor, you may end up using only two gears. One is a high-RPM gear so you can pedal along at top speed, and the second gear is extra low, for pedaling home when the battery is dead.

 

[efMX Trials Electric Freeride]

Hi everyone,

I planning a high power ebike build using an enduro frame which I plan to get registered as a moped and use for my 30 mile commute. I'm in the process of getting the parts together.

I understand the qs v3 hub motor is considered one of the better ones the only drawback seems to be that it will only take a single speed gear on the back. Ideally I'd like to put a six speed super range cassette on the back so that if it breaks down I can at least move the thing with the pedals.

I'm going to put a schlumpf drive on the front so I've got a high enough gear ratio so that I can still pedal when it's going pretty fast.

Can anyone recommend a hub motor which has space for a cassette? Or am I wrong about the qs motor?

Thanks!

by "enduro frame" do you mean a bicycle or ebike frame.. bc that will effect what fits best etc..

 

[john61ct]

Here's a second option, which I am surprised more builders dont use. There are many frames with a 2-speed or 3-speed shifter on the front chainrings.

I recall Barent Hoffman did this with a 3000W hubmotor. The rear axle had a single-speed freewheel, and the bottom bracket (by the pedals) had a 3-speed derailleur.

With a high-speed hubmotor, you may end up using only two gears. One is a high-RPM gear so you can pedal along at top speed, and the second gear is extra low, for pedaling home when the battery is dead.

I guess the front Schlumpf serves that function? The "mountain" version has a decent spread

 

[matthillster]

One of those ebike frames with a hollow central compartment with the battery etc in. Like the Stealth bomber ones but not so heavy.

Hi everyone,

I planning a high power ebike build using an enduro frame which I plan to get registered as a moped and use for my 30 mile commute. I'm in the process of getting the parts together.

I understand the qs v3 hub motor is considered one of the better ones the only drawback seems to be that it will only take a single speed gear on the back. Ideally I'd like to put a six speed super range cassette on the back so that if it breaks down I can at least move the thing with the pedals.

I'm going to put a schlumpf drive on the front so I've got a high enough gear ratio so that I can still pedal when it's going pretty fast.

Can anyone recommend a hub motor which has space for a cassette? Or am I wrong about the qs motor?

Thanks!

by "enduro frame" do you mean a bicycle or ebike frame.. bc that will effect what fits best etc..

 

[matthillster]

Yes that's true. I was hoping to have a bit more options for gears though. Maybe it's not necessary though.. I've never ridden a high power ebike.

I have a haibike sduro at the moment with a hub drive motor which needs the same gears as a regular bike but then the motor is a fraction of the power.

Here's a second option, which I am surprised more builders dont use. There are many frames with a 2-speed or 3-speed shifter on the front chainrings.

I recall Barent Hoffman did this with a 3000W hubmotor. The rear axle had a single-speed freewheel, and the bottom bracket (by the pedals) had a 3-speed derailleur.

With a high-speed hubmotor, you may end up using only two gears. One is a high-RPM gear so you can pedal along at top speed, and the second gear is extra low, for pedaling home when the battery is dead.

I guess the front Schlumpf serves that function? The "mountain" version has a decent spread

 

[efMX Trials Electric Freeride]

One of those ebike frames with a hollow central compartment with the battery etc in. Like the Stealth bomber ones but not so heavy.

Hi everyone,

I planning a high power ebike build using an enduro frame which I plan to get registered as a moped and use for my 30 mile commute. I'm in the process of getting the parts together.

I understand the qs v3 hub motor is considered one of the better ones the only drawback seems to be that it will only take a single speed gear on the back. Ideally I'd like to put a six speed super range cassette on the back so that if it breaks down I can at least move the thing with the pedals.

I'm going to put a schlumpf drive on the front so I've got a high enough gear ratio so that I can still pedal when it's going pretty fast.

Can anyone recommend a hub motor which has space for a cassette? Or am I wrong about the qs motor?

Thanks!

by "enduro frame" do you mean a bicycle or ebike frame.. bc that will effect what fits best etc..

well at least by starting with an "enduro" brand ebike frame you will have clamping dropouts and a large enclosed battery space.. however, where are you located, bc depending on where you live registering and insurance for home build may be the most difficult part of the project, if not impossible.. especially with the 5kw power levels described..

 

[MadRhino]

The motor is not a problem, the frame is. A wide freewheel on a wide motor does require extra wide frame.

Then, high power motors are generally used to build fast and powerful bikes, and those are not the kind that riders are feeding any pedal input. I mean, you can help half a horse with pedal input, improving efficiency, power, speed. Yet, you can’t pedal any help to 25 horses.

If you think 3 or 5 kw motors because it is what you plan to feed, you should know that those numbers are continuous power running on a test bench. On the street, you can safely feed 5 kw in acceleration to a 1000 w motor. Many of us are feeding 3 kw motors 25 kw in acceleration, and they last. So my advise is to buy a smaller motor if you plan to pedal, or to forget about pedal input if you build with a big hub. We build them single, and geared to pedal easy when power is off.

 

[matthillster]

That's a great idea but I don't think there's anywhere to attach a front derailleur on a EEB frame.

Here's a second option, which I am surprised more builders dont use. There are many frames with a 2-speed or 3-speed shifter on the front chainrings.

I recall Barent Hoffman did this with a 3000W hubmotor. The rear axle had a single-speed freewheel, and the bottom bracket (by the pedals) had a 3-speed derailleur.

With a high-speed hubmotor, you may end up using only two gears. One is a high-RPM gear so you can pedal along at top speed, and the second gear is extra low, for pedaling home when the battery is dead.

 

[dogman dan]

You'll only pedal in an emergency/ breakdown. Just put a tiny front gear on it, and have one, very low, emergency gear for pedaling.

Then the single gear in back will be fine. Make it of course, big as you can find in a single gear freewheel.

Clown pedaling when a cop sees you still works in any gear.

 

[spinningmagnets]

 "That's a great idea but I don't think there's anywhere to attach a front derailleur on a EEB frame"

I never said it would be easy. DP420 is reported to be very strong, if you dont want to attach a mount by drilling into the frame. You may need to construct a custom bracket. I recommend thick aluminum to start. Easier to cut and drill. If it doesnt turn out to be strong enough, you can just make a prototype from aluminum, and when you're happy with the design, remake the custom bracket in steel.

I believe this will be much easier and cheaper than modifying the dropouts on the swingarm, but..best of luck with whatever you decide.

 

[999zip999]

I have a 52t and 7sp with 11t and can peddle at 32mph it goes 43mph. Maybe you need a 56t front or do you want to peddle at just lower speeds ?

 

[matthillster]

It would be nice to pedal at high speeds but I guess not essential.

Have you got a hub motor?

I have a 52t and 7sp with 11t and can peddle at 32mph it goes 43mph. Maybe you need a 56t front or do you want to peddle at just lower speeds ?

 

[999zip999]

I have the muxus 4t v3 aluminum stator @ 4,500 watts with 15fet was 7,000 watts with 18 get. Batteries 24s A123 20ah 6.5 years old 1,480 charge cycles. Have the first verison 3,000 5t and melted it on a hill at 7,200 watts. It's heavy and battery is heavy. But the Q's 5,000 is heavier. What tires and rims are you going to run ? Have temp sensor and ca v3 but not hooked up. Bad.

 

[markz]

You can't pedal at high speeds. You'd need like a huge crank gear to your 11 tooth rear freewheel cog.
Largest road crank gears are like 52T, some 54T, surely there are some 60'ish tooth gears.
No name crank gear for 58T - https://www.amazon.ca/Chainring-Narrow-Mountain-Folding-Optional/dp/B07QMG113G/ref=pd_sbs_468_5/143-7577930-7306761?_encoding=UTF8&pd_rd_i=B07QFCGQT5&pd_rd_r=e29d11f5-dce9-4458-8d45-f39abebd8c6a&pd_rd_w=0BJlo&pd_rd_wg=UWFZu&pf_rd_p=74b54c94-7195-4620-ba51-7d167ac58a58&pf_rd_r=EMRZNQKYZ4SJQFZN11B0&psc=1&refRID=EMRZNQKYZ4SJQFZN11B0

Good luck with finding a derailleur to use the other crank gears.

It would be nice to pedal at high speeds but I guess not essential.
Have you got a hub motor?

 

[john61ct]

The Schlumpf gives another 1.65 overdrive

The example they give is combining with a Rohloff, gives 868% total gear range.

Not that I know how to run the numbers, but seems to get up to pretty high speed where pedaling would still be contributing enough to keep warm?

I realise that when you get to a heavy 5kw bike, pedalling isn't contributing that much but I'd like to be able to pedal to keep fit and stay warm in winter.