Can I swap/upgrade my hub motor?

[Ridersofthenorm]

Hi all. I have a Cafe Cruiser by ride1up. After a ton of research, it seems like there is some QC issues with some of their motors and recently in the fb groups, and some forums, there are people like myself disappointed in it's power.

I'm aware motors will put out whatever you feed it, but the rpm on this motor is low and it's hill climbing is weak. There are also reports of the motor frying itself when going uphill at 18A. Ride1up has recently limited the Cruiser to 18A from it's previous 22A because of reports of it frying itself and yet it still can fry itself at 18A.

https://imgur.com/iPUqHJI

I'd like to also note that there doesn't seem to be any grease on their planetary gears, or if what I do see is grease and not bits of melted nylon then I'd argue it's not greased properly. You can see where their's heated up and started damaging teeth and probably even binding.

I live in a hilly area that's also very windy and this motor is so much weaker than my 36v (48v battery overvolted) 750W ebikeling motor that it frustrates me every time I ride it.

So I would like to begin looking at options to replace this motor and upgrade it. I have done a lot of digging at the motor is a:

Bafang H620 RM G040.350/500.DC that Ride1up says is custom wound for 750W sustained. However, the tires are 26x3.0". A mechanic in the Ride1up forum says the rims are 46mm wide. This means I can't just swap the wheel to upgrade.

What, if any, motors will fit in this wheel? Or am I going to have to somehow build a wheel around a new motor? Are there any other Ebike companies with a good hub motor that have 26x3.0" (46mm wide rim) wheels that I can order a spare wheel from?

The old name for this motor is apparently "Bafang CST". That is what manufacturers used to call it.

​

H620RM G040.350/500.DC Specifications Dimensions​

Spoiler

Specifications Dimensions / Size

Dimensions / Size A 32mm
Dimensions / Size B 164mm
Dimensions / Size C 44mm
Dimensions / Size D 15mm
Dimensions / Size E 41.9mm
Dimensions / Size OLD 138mm

 

[AHicks]

Usually when you see melted gears in a hub drive, it's due to the fact that heat generated by the (overheated) motor has things so hot inside that case they're the first to fail. Lack of lube isn't helping a darn thing, but it's generally not the root of your evil when looking at a set of melted gears.

I should also mention the fact that cooling inside these geared hubs (and mid drives), sucks! They are never going to take fully rated power for long distances for that reason. Guys needing that ability need to go with direct drive hubs for their ability to keep themselves cooled down MUCH better!

Point being, even if you install a 1000w geared hub, you will not have the unlimited power you think might be getting. Sure, capable of a lot more than a 500w, but they're plenty capable of overheating too, due to the design!

From the "can I do it" point of view, SURE! You can remove the motor you have and lace up ANY geared hub to that rim. Clearly there's some variables that will come into play - like the drive line and controller wiring for instance - but nothing insurmountable.

 

[Ridersofthenorm]

Usually when you see melted gears in a hub drive, it's due to the fact that heat generated by the (overheated) motor has things so hot inside that case they're the first to fail. Lack of lube isn't helping a darn thing, but it's generally not the root of your evil when looking at a set of melted gears.

I should also mention the fact that cooling inside these geared hubs (and mid drives), sucks! They are never going to take fully rated power for long distances for that reason. Guys needing that ability need to go with direct drive hubs for their ability to keep themselves cooled down MUCH better!

Point being, even if you install a 1000w geared hub, you will not have the unlimited power you think might be getting. Sure, capable of a lot more than a 500w, but they're plenty capable of overheating too, due to the design!

From the "can I do it" point of view, SURE! You can remove the motor you have and lace up ANY geared hub to that rim. Clearly there's some variables that will come into play - like the drive line and controller wiring for instance - but nothing insurmountable.

Thanks, what I'm wanting to do though is try to find a motor that will fit without having to lace it up.

 

[indianajo]

I've had 4 types of hub motor, 3 geared. None were the same diameter. One had minimal grease on the gears.
Geared hub motors are not suited to long upgrades at full power. One manufacturer MAC stated an hour limit. I ride 77 hills in 3.5 hours with geared hub motors, but they are rollers. Momentum from one hill carries me partway up the next.
Direct drive hub motors have wimpy torque at slow speed, but they do cool better. Ferrofluid can be inserted in them to improve cooling.
I suggest if you do lace in a new motor use DT Swiss or Sapim spokes. So you don't have to tighten them frequently the way mystery metal spokes require.

 

[AHicks]

Be very careful who you are listening to/buying from! A lot of people have been ripped off making this move. They're charged a lot of money for a supposed 750w motor (core) that turns out to be a 500w....... or even a 350w.

Picture below has the 750w RAD Rover upgrade kit showing on the right. Issue for you is I don't believe this would fit your bike as you don't have a drop out dimension wide enough. This kit is for a fatty. I'm not sure it's even possible to convert a regular width motor. That motor you have listed above is showing it has a 138mm drop out/OLD dimension. Fatty's are generally 170-190mm (way wider, and no, yours cannot be spread). Even if/when you decide to re-lace to convert to a larger motor, that 138mm drop out/OLD dimension will be key as the NEW motor will need to fit there, making them pretty unusual/difficult to find.

 

[harryS]

If the motor core fits, it will likely have the same power capability and also the same result under the same load. The G60 motor swaps only work because they use thin and thick cores in the same motor housing,
.
Yeah, you might get 2.3" tires to fit on an ebikeling rim. Ask a bike shop what they would charge to respoke an ebikeling motor into a 44mm rim,
.

 

[m@Robertson]

The G060 motors were commonly upgraded because Bafang used the same external casing for an EU-spec 250w motor, which was in fact identical to the 350wmotor core (only difference wass the engraving on the motor outside). Also the 500w version could be swapped in as it had the same physical parts with more copper windings. The 'bigfoot' 750w version actually filled the casing and was - as you can see - a big upgrade. Those motors have been subjected to 2 kw continuous power with custom controllers, and more commonly 1500w peaks.

There were other details like the 750w motors had a bigger plug to handle the increased current, and the Rad models had the big plug on them so they could visually mimic a real 750... but none of that matters to you.

You have a G040 and not a G060. There appear to be only two G040's - the 350w and the more powerful 500w. And you already have that one. There's nowhere to go. So on this motor casing, you are not going to be doing a simple motor core swap to upgrade. Its likely then you will need a whole new motor, controller, display, throttle... the whole bit. Somewhere like Grin Technologies is where I'd look for a proper quality kit. The kind of money involved probably makes this an option you won't want to pursue.

 

[indianajo]

If the motor core fits, it will likely have the same power capability and also the same result under the same load. The G60 motor swaps only work because they use thin and thick cores in the same motor housing,
.

I've had a 1300 W ebikeling motor in 135 dropout, also a 1000 w Mac12t in 135 mm dropout. Both were quite torquey. Both would start 330 lb gross on 15% grade and accelerate to 6 mph without help. Ebikeling motor wore out the gears ~4500 miles, Mac12t wore out the one way clutch ~2500 miles. Mac12t clutch was slipping when I got it, kept it because it was last one in USA. 3 class laws have outlawed these motors. People climbing 15% grades at 6 mph are too dangerous to ride bicycles on roads. State legislatures have spoken!

 

[tomjasz]

One manufacturer MAC stated an hour limit.

Where ever did you mine this BS?

kept it because it was last one in USA

You keep posting this bad information. MAC motors are readily available from MAC. Reliable and safe source. No advantage with a USA source.