1000w or 1500w? Power/range differences

[Debunker]

Hi pipol.

I want to make a e-bike, I live in very forest/hills terrain, so I wanted a bafang or something mid drive to play with the gear ratio, but sadly I can't install that type of kits in my bike due to weird shape of the frame, so I'm limited to a rear hub.

I then search for a geared rear hub, but men... this is too expensive in comparison.

Now I'm watching a 1000w/1500w kit, and I wonder what are better in a 48/52v config. I heard that there is really not much difference.

Does the 1500w worth the extra price? will I get slightly more power but much less range? Is it better to use more power to climb hills instead of make the motor suffer slowly and go slow with high voltage?

So many cuestions...

 

[neptronix]

If you have serious hills then i'd say it's worth the cost to buy more power than you need.
..you may even want more power than that.

rear hubs aren't too bad but if you're doing offroad etc you may want to spend some money on a hub that's particularly light so that you can minimize unsprung weight in the rear..

AFAIK the current winner of the DD hub motor density contest is ebikes.ca's RH212, which should qualify as ~1500w rated per our tests, and is something like 13.3lb.. versus my previous favorite, the leafbike 1500w, which comes in at ~16lb. The RH212 motor also has a few extra poles, so in a 26" or 29" wheel, it should perform pretty well when climbing significant hills.

The ebikes.ca simulator is a bit of a beast to learn for a newbie but it should answer a lot of your questions about range, climbing ability, and power on a number of potential motors and battery configurations.. give it a look:

https://ebikes.ca/tools/simulator.html

 

[lnanek]

As a road commuter with a rear hub, I find top speed kind of lacking on 48V setups. It's often like 24-28mph vs. 32-35mph. No clue about hills.

If you really want a mid drive, there are ones with an extra chain that allows the motor to be placed strange places like inside the triangle. For example, the CYC X1 PRO Gen 2.

 

[999zip999]

Can't get my cyc gen 2 pro to work.
Get a bafang
Just look on craigslist for a bike it will fit....
Check for battery fit and?
Make a cardboard box the size of the battery and carry it witch you when buying bike.
What bike do you have now
Rear d.d. motor 1,000 watt may have 28mm satator.
The 1,500 may have 35mm stator.
You need 35mm startor. And 52v 20ah battery with good quality cells yes a good battery maker will tell you what exact cells they have Samsung 30q Panasonic you know check it out check the charts make sure the battery is over built for your needs don't get some cheap Abba zaba Chinese junk.

 

[electric_nz]

Look at a bafang bpm 500W geared hub on a 52V battery, easily handle 1000w probably 1500w, and will go up steep hills.

Direct drive are good once they get going but not fast for cold start up hill.

 

[E-HP]

Hi pipol.

I want to make a e-bike, I live in very forest/hills terrain, so I wanted a bafang or something mid drive to play with the gear ratio, but sadly I can't install that type of kits in my bike due to weird shape of the frame, so I'm limited to a rear hub.

I then search for a geared rear hub, but men... this is too expensive in comparison.

Now I'm watching a 1000w/1500w kit, and I wonder what are better in a 48/52v config. I heard that there is really not much difference.

Does the 1500w worth the extra price? will I get slightly more power but much less range? Is it better to use more power to climb hills instead of make the motor suffer slowly and go slow with high voltage?

So many cuestions...

Everything starts and ends with the battery, so if you can describe what your plan is for that, and what your budget is, then it would be easier to help. From your comment on the geared hub, obviously there's a budget constraint, so that would help, rather than people suggesting things, and you shooting them down due to costing too much. You requirements/wishes will likely need to be flexible, if you have a dollar limit, so don't keep that a secret.

 

[Debunker]

Thank you all, well I finally choose a 1500w rear hub and I just finished mounting everything.

The bike has a aluminium frame and already destroyed another hub motor in the past, when the wheel goes upside a hill out of their own destroying the cables, that was a geared 1000w with a lot of torque.

The alu frame was a bit cheewed, so I put one of those torque arms on one side, and a solid 3d printed piece on the other fixed on the brake disc position ( I use V brake), for now that's all I got, but I plan on buying a 3mm steelplate and file it to replace the crappy plastic one before I take a ride on serious hills.

That's almost all done, tomorrow I plan on test it in a flat, easy trip, now I only have one more thing to consider.

The battery are labeled as ChamRider hailong 21700, not specified the brand of the inner cells... I doubht they are panasonic or samsung, I guess just generic ones, 48v 24ah. The bms says it will stand 40amp continuous.

On their side, the controller says it will deliver 35amp maximum, I have configured the lcd to a limit of 33amp, 2 minus the max of the controller. Is that acceptable in this config? cause it comes configured with 20 for 48v on default and I don't know if I'm overdoing.

Edit: I just see the vendor's description, it seems it has 15 mosfets and 35 is the rated amp, and 70 is the max, so I guess I can config it to 35 with no problem, or should I...? the battery max is 40, but those are generic unbranded cells so I don't know.

 

[99t4]

I see three serious flaws in your TA implementation. With 1500w, axle spinout becomes a serious possibility and requires serious countermeasures.

1. Poorest quality comercially available TA. Bet that was the cheapest one you found, correct? Not good enough. Almost certain that the section that slides over the axle fits it loosely, where it can rock back and forth on the axle. No good, it must fit snugly, the harder it is to slide on the better. For 1500w hubmotor, the Grin Tech TorqArm_V4 is what you want: https://ebikes.ca/product-info/grin-products/torque-arms.html

2. The hose clamp is not fastened in a stable secure manner. Better to simply clamp it around one stay only. (In your case, the seatstay.) The way you have it all twisted and extended, stressed, ready to slip down towards the dropout, it's not doing much real good.

3. Plastic 3d printed TA? If you got that idea from here (ES), that was probably a mock-up, to be used as a model for fabricating the real TA out of steel or aluminum. Plastic not strong enough to serve as a TA.

Avoid spinout problems again, invest in something that will actually be effective.

 

[Debunker]

I see three serious flaws in your TA implementation. With 1500w, axle spinout becomes a serious possibility and requires serious countermeasures.

1. Poorest quality comercially available TA. Bet that was the cheapest one you found, correct? Not good enough. Almost certain that the section that slides over the axle fits it loosely, where it can rock back and forth on the axle. No good, it must fit snugly, the harder it is to slide on the better. For 1500w hubmotor, the Grin Tech TorqArm_V4 is what you want: https://ebikes.ca/product-info/grin-products/torque-arms.html

2. The hose clamp is not fastened in a stable secure manner. Better to simply clamp it around one stay only. (In your case, the seatstay.) The way you have it all twisted and extended, stressed, ready to slip down towards the dropout, it's not doing much real good.

3. Plastic 3d printed TA? If you got that idea from here (ES), that was probably a mock-up, to be used as a model for fabricating the real TA out of steel or aluminum. Plastic not strong enough to serve as a TA.

Avoid spinout problems again, invest in something that will actually be effective.

The V1 is indeed the cheapest, but honestly I see all of them as the same crappy concept, if the wheel wants to jump out, the best I can hope for those things is that it will retain the wheel to some degree and hopefully prevent the cable twisting destruction like in the last time, so I can go home dragging the frocked e-bike all the way back like in the last time, but with the motor intact.

I print the plate on the other side of the frame in the strongest plastic I have, Petg, but I know it's just a temporal solution, I want to get my hands on a 3mm thick steel or titanium plate, then I will remove the plastic one and use it as blueprint over the plate to make the holes with a dremmel, the trick part will be to make the rectangular shape, I guess its just a lot of patience and post manual work with a file to end up with a custom proper plate.

Until then I don't plan to ride on hills and hard terrain.

 

[LewTwo]

... the trick part will be to make the rectangular shape ....

Manual milling machine (flat file, elbow grease, time and patience).
... or you can draw an outline and have the plate cut by laser or water jet ...
of course that tends to be a tad more expensive :|

 

[donn]

The hose clamp should be simple to fix, though. Like the man said, simply strap it to the seatstay.

 

[99t4]

The V1 is indeed the cheapest, but honestly I see all of them as the same crappy concept...

Nope.

The Grin Tech TA is close machined of quality material to tight tolerances, thick enough to secure the axle effectively.

The cheapo broached soft steel type you used has several faults. Sloppy fit allows the axle to rock back and forth (eventually spinning out), combined with not being thick enough to hold the axle well. And the "quarter moon" slot for the hoseclamp can actually slice the hoseclamp, depending on its orientation. (What were they thinking? :?)

What does your plastic 3-d printed TA look like? Maybe you can fab a metal one using that as a template?

 

[Debunker]

The red thingy... I have to remove a good chunk of it because the weird shape on the arm. I plan on buying a 3mm steel or titanium plate and use it has template, but I will need to work with less than apropiate tools for that, and I will probably spend hours making holes and shaping with a file.

 

[portals]

Re the TA, always try and clamp it to the chain stay and not the seat stay, they are stronger and they connect to the bottom bracket, make sure and torque up the jubilee clamp with a large wrench as tight as you can get it, do not try with just a screwdriver...

There are thicker width ones for non-drive side available online (Hammer), replace the cheap one

I have 1500W rear hub and 52V 17.5Ah battery (samsung), you will not regret going 52V for the extra power available if you need it, make sure and buy branded battery packs not cheap chinese cells (18650 cheapos are $1, samsung are what $6, you get what you pay for).

I'm in process of designing my own TA for drive side, I've 3D printed a few prototypes mentioned on another thread in PLA+. No way PETG or ABS or even nylon will help under torque, when I'm happy I will get it laser cut on advice from another member, I can get it in two 4mm pieces held together by two derallieur bolts so cost is much lower than CNC machining.