Help me understand what i just bought... Was i ripped off?

[neptronix]

Good for you ! I do the same lifestyle of low carb , but I am a bodybuilder . I believe sugar is the biggest enemy in the diet of Americans. As you know, losing the weight is not as hard as keeping it off . I can stay away from most of the sugar products, but anything with potatoes , is my weak point. The other major factor is drinking water .

I'm a type 2 diabetic.. so staying on this diet is pretty easy for me because i am asymptomatic when i stick to it. I also don't have chest pains, scary episodes of lightheadedness and flushing etc anymore.

I made a post about it on reddit a bit ago:

https://www.reddit.com/r/keto/comments/6aqf03/what_almost_4_years_of_ketogenic_dieting_did_to_me/

I've just barely started bodybuilding myself. I'm a clueless newb in that area.

 

[rumme]

Good for you ! I do the same lifestyle of low carb , but I am a bodybuilder . I believe sugar is the biggest enemy in the diet of Americans. As you know, losing the weight is not as hard as keeping it off . I can stay away from most of the sugar products, but anything with potatoes , is my weak point. The other major factor is drinking water .

I'm a type 2 diabetic.. so staying on this diet is pretty easy for me because i am asymptomatic when i stick to it. I also don't have chest pains, scary episodes of lightheadedness and flushing etc anymore.

I made a post about it on reddit a bit ago:

https://www.reddit.com/r/keto/comments/6aqf03/what_almost_4_years_of_ketogenic_dieting_did_to_me/

I've just barely started bodybuilding myself. I'm a clueless newb in that area.

Ive been bodybuilding naturally since I was 14 years old and I am now 50 . If you have any questions, just ask and I will answer.

 

[d8veh]

Ive built ebikes with direct drive hub motors and geared hub motors. I think the geared hub motor isn't worth it. They can be noisy, they have more parts to break, and they seem to generate ALOT of heat . The bafang 750 watt nominal geared hub motor I tried, was GARBAGE....my cheap direct drive 1000 watt yescomusa hub motor performed better and it was less expensive .

I've never heard of a 750w geared Bafang hub-motor. In fact, I can't think of any brands that make a 750w one. Can we have some more details please?

 

[rumme]

Ive built ebikes with direct drive hub motors and geared hub motors. I think the geared hub motor isn't worth it. They can be noisy, they have more parts to break, and they seem to generate ALOT of heat . The bafang 750 watt nominal geared hub motor I tried, was GARBAGE....my cheap direct drive 1000 watt yescomusa hub motor performed better and it was less expensive .

I've never heard of a 750w geared Bafang hub-motor. In fact, I can't think of any brands that make a 750w one. Can we have some more details please?

No problem...heres the exact one I purchased....and I think this same motor comes on several premade ebikes..like the RAD ROVER....anyways, it did not impress me.


http://www.ebay.com/itm/8Fun-Bafang-48V-750W-Brushless-Geared-Threaded-Rear-Hub-Motor-175mm-For-Fat-Bike-/292028451661?hash=item43fe408b4d:g:1OMAAOSwfVpYozDe

Furthermore, I was so disappointed with its performance, and how HOT the motor got when I would pump 2000 watts in it, for short bursts, I did some cooling mods . I started out with the ATF cooling mod, and that was terrible...because you eventually get leaks, and the motor still gets very hot, because the heat is still staying trapped inside a mostly closed system. I still think cooling holes cut into side covers is 1 of the best methods, because it allows the heat to exit the motor quickly.

 

[neptronix]

I'm surprised that motor even survived 2000 watts!
A MAC would be a lot better, but still far from what you're looking for.

Also, thanks for the bodybuilding help offer.

 

[rumme]

I'm surprised that motor even survived 2000 watts!
A MAC would be a lot better, but still far from what you're looking for.

Also, thanks for the bodybuilding help offer.

It didn't like 2000 watt bursts , and even at that higher wattage, I thought it performed poorly...worse then my YESCOMUSA direct drive hub motor, which you know is a entry level motor.

 

[DoubleM]

I forgot to mention something i don't know if its important or not.

When the bike faces those uphills the battery meter drops from 5 bars (full) to only 2.

About my question regarding the controller limit in the lcd. How that parameter works? It's used to lock to lower Amps the controller is able or it could work like an "overclock"? Lets imagine the controller is rated at 12 Amps, if i change the parameter to an higher number it will give more amps or no since it's already in it's max?

 

[neptronix]

I forgot to mention something i don't know if its important or not.

When the bike faces those uphills the battery meter drops from 5 bars (full) to only 2.

Right. Your battery voltage is dropping due to internal resistance on load. You'll notice this results in heat in the battery. The battery is worn or not adequate for what you are doing.

A battery that can output more amps will give you a power boost just because the voltage remains steady. It will also last longer.

I would not increase the amp draw on a battery like that.. actually i'd reduce it, unless you are okay with trashing the battery in a year or two.

What would be really helpful is to have an actual watt meter so you can see more of what's going on, rather than these LCD screens which are generally useless as they don't show realtime amps/volts/watts.

 

[Sunder]

That's quite a sag for a Samsung 10ah battery on 12 amps... you sure it's legit? So many inferior copies these days. So many of them charging near RRP too, makes it hard to avoid the "cheapies".

 

[d8veh]

Those batteries, when loaded with the cheaper cells do sag a lot, so what you see is normal; however, it shouldn't be that bad at only 12 amps.

You should try setting the current to 18 amps as a temporary measure, to see if it solves your original problem. It won't do any damage to your controller or battery in the short term. Your controller can probably go to 25 amps or more before you start to get heat problems. I've got a feeling that it's already set to more than 12 amps, but we need to check that by seeing the difference. It's not a case of overclocking. the controller wouldn't have a 20 amp setting if it wasn't made for it. The setting doesn't even take a minute, so do it, go out for a short ride, then feel how hot the controller gets to reassure yourself.

Contrary to what has been said, I always found the watts showing on the LCDs to be pretty accurate when compared with decent wattmeters. The battery displays are also quite accurate as voltmeters, but you need to check at which voltages the display switches off the bars. Also, they normally have a damping factor, so you have to leave them to settle to get an accurate reading. Yours might not be damped, which is why you see so much sag.

 

[DoubleM]

Today i took a ride and i changed the parameter to 18 amp and i really can say i felt a difference. It didn't turn in an amazing hill climber and it still doesn't climb 10% hills only on throttle but i could feel the difference in easier hills like 4/5%. It doesn't drop as much speed as before. And now the lcd shows 600+ Watts, so not a placebo effect.

However, i don't know why, but after a while, like 5km or so, the PAS got really really weak. I felt the motor engaging but the help is close to nothing. I tought maybe it was the battery but it was almost full in the LCD and then i checked with a multimeter and it was at 49v not under load. However if i throttle it has the same power as before.

I have the battery charging and i´ll try tomorrow again if it doesn't rain but it was really strange.

Edit: Solved, it was the magnets that moved away from the sensor.

 

[d8veh]

650w is still very low. You should be seeing something like 900w when you pull away from a standstill with max throttle or PAS. In that situation, do you see a difference in watts between the PAS and the throttle?

 

[DoubleM]

650w is still very low. You should be seeing something like 900w when you pull away from a standstill with max throttle or PAS. In that situation, do you see a difference in watts between the PAS and the throttle?

Sorry for the delayed reply, i had the bike in the mechanic to shifting adjust.

Today i was testing and i was never able to see more than 2xx Watts in PAS. However with the Throttle it reaches 6xx under full load. I don´t know if the PAS only kicks in at its max power under very specific conditions or not. If so, please let me know how should i test it.

I was looking and theres one think i noticed, which i don't know if it can cause issues or not. I´ll try to explain the better i can, i'm a newbie in this area and English is not my main language, so it doesn´t help neither.

It seems when they did the conversion they mounted the PAS disc and sensor on the "wrong" side. It isn't in the chain side but in the other side. So, in order the disc to have the arrow pointing to the right rotation, the disc had to be placed with the magnets facing outside. I can post a picture if needed. Do you think this can cause any trouble or the final result is the same?

Besides that i noticed the disc has 8 magnets and if i set to 8 in the LCD the PAS doesn't work. It only works if it's setting up to 5 (which was the default value).

 

[d8veh]

Those things shouldn't have any affect on power. The PAS wouldn't work at all if the magnet is the wrong way, so it's correct. Are you selecting the maximum PAS level on the LCD?

 

[DoubleM]

Yes i am.

In fact that setting controls both throttle and PAS.

Theres some hidden settings i need to try again to see if theres any difference. I´m speaking mainly from setting number 11, which is PAS sensivity, but i guess it only should change the kick in sensivity, not the power assist... And watching the video i didn't get what has more sensivity, if a lower or an higher number.

My LCD is this one, except it has two more settings i have no ideia which are (16 and 17).

[youtube]z1N3hjtv3jo[/youtube]

 

[heavymetalthunder]

It sounds like you are getting the performance expected of a DD 500w motor. I have a 1000w dd at 48v and on steeper hills my systems gets a good work out. There is even hills in my area that my 1000W dd can barely handle, it is a slow climb and takes a bit of battery power, I use anywhere from 15ah to 20 ah Lipos that are at least 20c rated and they have little problem handling the load.. DD are good on flat terrain with mild hills. The other thing that might help you is to use road tires and not the mountain bike tires.