New Bafang Crank-Drives

[opperpanter]

Anybody knows anything about these new "Max Drive" middenvelder from Bafang?

http://www.szbaf.com/

It looks like it's for OEM as it uses a proprietary frame.

So we buy a motor AND a frame

 

[tomjasz]

Sowe buy a motor AND a frame

Would you be kind enough to point to the frame available for purchase?

 

[opperpanter]

Sowe buy a motor AND a frame

Would you be kind enough to point to the frame available for purchase?

Check the

 

[tomjasz]

 

[teslanv]

Here is a shoutout to all Bafang BBS02 owners - Please respond to the survey and post a short review here:

http://endless-sphere.com/forums/viewtopic.php?f=5&t=70294

 

[tahustvedt]

I bet you've never seen one of these before.

 

[tomjasz]

WTF? That's not nice!

25Amp rated to run 15 MPH?

 

[tahustvedt]

Custom adapted by Bafang for a norwegian distributor to perform the same as Bosch, Yamaha and Impulse "250 W" motors. It's limited to 15 A PAS, but the limit is raised to 25 A when a thumb throttle is pressed (which only works while pedaling).

 

[d8veh]

You should be happy, Tom. The main thing is that it has the 25 amp controller. You can re-program it to whatever speed you want. It's the 250w marking that's important for those that have to comply with EN15194 and similar.

 

[tahustvedt]

I'm not complaining. I just bought it.

 

[Ade]

You should be happy, Tom. The main thing is that it has the 25 amp controller. You can re-program it to whatever speed you want. It's the 250w marking that's important for those that have to comply with EN15194 and similar.

What's the top speed if not limited I wonder...?

 

[tomjasz]

You should be happy, Tom. The main thing is that it has the 25 amp controller. You can re-program it to whatever speed you want. It's the 250w marking that's important for those that have to comply with EN15194 and similar.

It's hard to be excited about any 8fun controller given the continued failures. I'm hoping the 3077 FET rumor pans out.
The 18 amp wasn't broken. IMO.

 

[tahustvedt]

25 A just means going a lot faster uphill. It will probably go 25 km/h in all the hills I'm likely to encounter. The BBS01 250 W motor is limited to 15 A.

Riding the BBS like a moped is bound to break something.

 

[tomjasz]

Riding the BBS like a moped is bound to break something.

Not yet...

 

[alfantastic]

Riding the BBS like a moped is bound to break something.

If you ensure that you change gear with the motor power off or on a low PAS/throttle setting, and select the correct gear for hills, then I see no reason why the unit or bike will break.

It appears to be a robust little system, if the rider adapts to how it likes to be treated :wink:

 

[tahustvedt]

Ok. I thought the controllers kept breaking.

 

[alfantastic]

Ok. I thought the controllers kept breaking.

I reckon the controller problem has been over hyped. If the motor is not allowed to be put under extreme stress, then the controller will get an easier time too.
Using the wrong gear at too slow a speed is the bad guy here.

I always allow the motor to spin nice and fast, and you can tell when it's happy by listening to the noise it makes.

Mine makes a faint happy whine, when its working in it's happy zone. Hee hee, I couldn't think of any other way to word this

Knowing my luck, the controller will explode tomorrow and blow my theory out of the water

 

[leelorr]

+1
Before I got my 25 amp 750 watt Bafang BBS02, I thought I would need to be very cautious in using the power. I have since found that if I keep the bike in a gear that would make sense for a human to be pedaling in those conditions, my unit has never even been very warm to the touch. If I use full manual throttle it can get hot pretty quickly because you can use over 1200 watts even when going slow or accelerating from a stop. If you let it work like it's designed to do, I think it works extremely well. I have also noticed that when using PAS, level 3 supplies about 500 watts, which seems to be plenty for everything I do.

 

[alfantastic]

+1
I have also noticed that when using PAS, level 3 supplies about 500 watts, which seems to be plenty for everything I do.

Exactly, apart from the obvious start up peaks, I'm averaging 600 watts on the display, even up the steepest of hills. That's only around 11 amps load from a 25 amp controller.
It's all down to selecting the gear that suits the Bafang the best. I'd rather go a little slower up a steep hill, if it means the motor is spinning nice and fast.

I think any previous experience with driving a stick shift/manual geared car, helps with understanding the relationship between engine speed/gearbox and wheel speed.

 

[opperpanter]

What chainring are you using when you say "let it work like it's designed to work"? I have the stock 44t chain ring and the motor is getting warm even when only going 20-30km/h (on throttle only).

 

[alfantastic]

What chainring are you using when you say "let it work like it's designed to work"? I have the stock 44t chain ring and the motor is getting warm even when only going 20-30km/h (on throttle only).

42Tchainring.

The motor might be feeling deceptively warm, due to the black casing absorbing heat from the sun. Wouldn't want it in white though
Traveling at slower speeds of 20-30km/h means less air flowing over the unit too.

I think the unit struggles to dissipate heat easily too, so once a fair amount of heat builds up, it hangs around for a long time.
Then any mistake with gearing or too much full throttle, takes it over the edge and poof... controller meltdown.

 

[leelorr]

I have a 42t front sprocket and have changed my rear gear cluster to be a 12-38 so that I can have a lower gear when on trails.
I have found though that using "throttle only" mode causes the motor to run much hotter because the amount of amps you feed to motor is not limited like it is when using PAS. I guess you could change the max amp settings but then you would be limited to that value all the time. If I use the throttle only I can get the unit hot pretty quickly. After all, you are dumping way too many amps into the motor because the human (you) has no idea how much of that power is producing usable power compared to how much of it is being converted to heat. I have watched my watt meter when using the throttle, and after a certain amount of power is sent to the motor when using the throttle, I can't even feel any more acceleration even though the watt meter tells me that I start using TWICE the amps if I add more throttle.

 

[spinningmagnets]

I have since found that if I keep the bike in a gear that would make sense for a human to be pedaling in those conditions, my unit has never even been very warm to the touch

I believe that a lot of the customers who have had a controller fail due to high sustained heat, they were using it as if it was a one-speed or sometimes a 2-speed. Nothing wrong If you are only using 3 gears out of 7 available, but if the motor and controller are getting very hot, you are doing something wrong.

 

[alfantastic]

I have since found that if I keep the bike in a gear that would make sense for a human to be pedaling in those conditions, my unit has never even been very warm to the touch

I believe that a lot of the customers who have had a controller fail due to high sustained heat, they were using it as if it was a one-speed or sometimes a 2-speed. Nothing wrong If you are only using 3 gears out of 7 available, but if the motor and controller are getting very hot, you are doing something wrong.

Precisely, just because the system is capable of moving from a standstill in top gear using full throttle, doesn't mean that it can do this repeatedly.

I can imagine that some riders feel it is a slight inconvenience, changing down a few gears ready to move off from a complete standstill, but it's what needs to be done for system longevity.

I had to completely change the way I ride, since I moved from a 48v 30A MAC 10T to the BBS02. Never needed to change from the 11T sprocket on the MAC lol.

 

[tomjasz]

I have a 52T chainring on one of my BBS01 350W. Typically I now ride in 3rd or 4th gear on a 7spd. BUT when I'm on the local bike path or flat roadway in 7th it purrs along at 26MPH on 11TX52T without getting beyond barely warm. I bought a temp gauge to monitor but don't think I'm going to bother installing it. Down shifting on ANY grade is critical. As has been pointed out, using common sense, NEVER taking off or loading up from a start above 3rd, and it's all good. BUT there have been controller fails resulting from the poor construction and cheap, cheap FET's, as well as programing errors from suppliers. There have been some unlucky riders who haven't abused their motors and lost controllers. From my view those numbers are pretty low. I still think this motor is best suited to commuting and medium duty. Although, electric fatbike, Karl puts his through the paces and seems to do well... he did replace FET's in one unit. I understand Bafang is listening and there may be improvements coming. I'd buy another in a flash and none of the bikes I built and sold are having any problems. (all 350W BBS01's) I like it SO much better than my two hub drives.