E-Bike "Tweeking" advice

[rylie]

I recently acquired a golden motor pro 901 hub with the standard external controller and 48v 10ah battery (not sure of any other specs on the battery). So far I like how the bike performs but I would like to "tweak" it and see if I can get a little bit more out of it. So my wish list as follows...

- A little more top speed. Currently around 40kph (25mph), would like around 50 / 55kph (30 /35mph)
- A little more torque for getting up hills
- A little more acceleration
- Also would like to try and combat the wind as much as possible

I have done a bunch of reading but I am seeking the advice of the follow ES members. If anyone can chime in with advise that would be greatly appreciated.

 

[cal3thousand]

Sounds like a controller upgrade would be the easiest.

You are already running 48V. You could go more, but that would require battery investment.

 

[rui_fujino]

If you want speed = more voltage
If you want acceleration = more amp
If you want torque = more fets

So, If you want all then go get better controller that can pull more amps.
if you want more speed then just increase the wheel to bigger size

 

[wesnewell]

Did you get the 500W or 1000W motor? Part number should be on the motor if you don't know (HBS-48V500/1000W(serial number)

 

[rylie]

I don't see any markings on the hub except what appears to be a serial number. As far as I know it is 1000w. Below is a clip from their website.

You no longer need a 48v1000w for off road and a 36v500w for on road riding.

Our Pro 901 Motors are now Multi Voltage like our Magic Pie motors.

At 36 Volts this kit is a 36 Volt 500 Watt Motor. It Performs well , climbs hils and on flat ground rolls along quite easily at 32 kph.

At 48 Volts this kit is a 48 Volt 1000 Watt monster! Is is our fastest motor and tops out around 50 kph with a 26 inch rim. Unless you use a Golden Motor USB cable to pull back watts and speed this kit is for offroad use only! It is up to you to abide by the local, regional, state and country Laws where you use our products Please read our legal!

 

[nechaus]

If you want speed = more voltage
If you want acceleration = more amp
If you want torque = more fets

So, If you want all then go get better controller that can pull more amps.
if you want more speed then just increase the wheel to bigger size

Yes more fets or better fets if the battery supply allows it.
It might be running at max c rate atm. So controller may not be the weakest link

 

[neptronix]

Your motor is basically a MXUS/9C. Same diameter, and i'm sure the magnet width is 100% the same.
So all the typical advice for those size motors applies.

So get yourself a real man controller ( 12FET minimum ), big ol' high voltage / high amp battery and start dumping more power into it.

However, more amps would be a start. I bet your controller is set up to do some 20A-25A weak sauce.. that motor needs 30A and above to wake up

 

[wesnewell]

I don't see any markings on the hub except what appears to be a serial number. As far as I know it is 1000w. Below is a clip from their website.

You no longer need a 48v1000w for off road and a 36v500w for on road riding.

Our Pro 901 Motors are now Multi Voltage like our Magic Pie motors.

At 36 Volts this kit is a 36 Volt 500 Watt Motor. It Performs well , climbs hils and on flat ground rolls along quite easily at 32 kph.

At 48 Volts this kit is a 48 Volt 1000 Watt monster! Is is our fastest motor and tops out around 50 kph with a 26 inch rim. Unless you use a Golden Motor USB cable to pull back watts and speed this kit is for offroad use only! It is up to you to abide by the local, regional, state and country Laws where you use our products Please read our legal!

Well, that's just BS. It's like saying my 1000W motor (part num. HBS-48V1000W) is a 4000W motor because that's what I can pump into it at 100V. The Goldenmotor website still list their motors as 500W and 1000W and a motor can't have both a 500W and a 1000W rating. Your max speed of 25mph is closer to their 500W motor as that's about what I got with the ones I bought. With the 1000W I got closer to 35mph using the same battery pack (14s lipo). So there is a difference. There 500W motors were rated for 380rpm @48V and their 1000W motor were rated for 470rpm @48V. Where did you buy your motor kit? Something sounds fishy to me. In any case, about all you can do is go to a higher voltage battery. Going to 72V (20s lipo) on my 500W motors gave me close to 35mph iirc, and of course with more volts comes more torque (acceleration). You will likely need a new controller for the higher voltage. Mine cost $35 shipped and supported up to 100V.

 

[Sunder]

I have a golden motor cheap ebay copy that's 1000w and it goes about 41 kmh with no pedaling and about 46 with - but that was with more like 44v since I was using a half charged 12s.

When someone says tweak rather than upgrade, my thought is they want to get more out of their current outfit rather than spend money replacing anything . That said, a new controller is probably going to be cheaper than tweaking, and asking for a 20% gain is not really tweaking.

My upgrade suggestions follow everyone else, but my tweak suggestions include:

Make sure all wires and connectors are suitable for their purpose - I've found if a wire says 25a max, then putting 25a into it gets it very warm and presumably is losing power and increasing voltage sag. So I always over rate my wires and connectors by one gauge. Also, if you're using stock wires, they're probably too long and contribute to the problem.

Make sure your tyre pressures are as high as the tyres will take. I run a 55/60 combo on mine - quite high for a mountain bike, but not even in road bike territory.

If you've recycled an older bike, make sure that all your bearings are still good - especially on the non driving wheel. You'd be amazed at what difference good bearings can make.

Make sure you've got the right seat and handle bar height on the bike. Bike geometry and consequently wind resistance makes a huge difference at high speeds.

Basically most of these are general bike maintenance tweaks - others have far more knowledge than I do about getting more out of, motor and controllers,but thought these might give you an extra 1-2km/h for free.

 

[dogman dan]

A higher amp controller is very likely to to a bit of a "tweak" to your battery. It may be howling in pain already.

So your tweak is going to have to be more than a tweak. But if you limit your amps to 20, you could get away with adding more voltage. New controller, in 72v 20 amps, and an additional battery for 24 more volts. It's a bit weak sauce, you won't have a 40 mph club motor, or spin your tire. But you will climb hills much better, have some better acceleration, and be able to hit 30 easily and eventually wind up to about 35 mph if it's flat.

You'll have about 1500w, so it's unlikely to melt down your motor.

The real tweak is a 72v 40 amp controller. That gets you the 40 mph club, but you will have to completely start over with new battery able to put out 40 amps. 3000w, but if you keep your rides short you won't melt the motor. Long ride, garanteed you will melt it.

 

[Drunkskunk]

The motor in those kits is decent. its truely a 500 watt MXUS/9C clone, and will perform well when pushed to pretty high power levels. you could double it's power output and still be safe.

The GM 1000w rating comes from the kit's peak output rating. Ebike motors aren't normaly rated that way. it has a 48 volt, 20A controller for total output of 960 watts, roughly justifying their 1000w rating.

But not with the rest of that kit. The battery is the weak link. It can't handle putting out more power than it currently is without damage. So that limits your options. Mostly just tweaking everything for greater efficancy with the power used.

The first thing I'd upgrade is the motor phase wires, and the battery wires. GM likes to use some thin wire. thicker wire will pass more currant and heat up less.

 

[dogman dan]

I wouldn't hesitate for 2 seconds to feed 1500w into any generic dd motor. Above that, it's just a matter of ride conditions whether it melts or when.

Back to tweaks that are possible cheap. lower the bars, lose the flappy coat and baggy pants, run hard tires. Only good for a few mph or a few miles more range. Even pedal your guts out has little effect past 25 mph.

 

[wesnewell]

Both the 500W and 1000W kits I I bought came with a 30A controller. A 12fet with the 500W and a 15fet with the 1000W. These were not GM controllers although the motors were. I don't know the specs on the GM controller. I replaced these with a $35 shipped Hua Tong 72V 40A 15fet 100V capable controller for more speed and torque. I've never had a problem with this setup. Now their motors are not the same. Testing both with the same controller and battery pack will make that very apparent.

 

[E-racer]

I wouldn't hesitate for 2 seconds to feed 1500w into any generic dd motor. Above that, it's just a matter of ride conditions whether it melts or when.

Agreed 100%