Bafang motor

[tostino]

Well i've been working on my chain drive bike for way too long now, and it's still not perfect. I would like to eventually get it working right, but at the moment, I just want something to ride.

I want to buy a bafang either front or rear motor for a steel frame cheapie. I have a e-crazy man controller modded to 20mhz, and want to run the bafang at 51v (14s). Will I run into frequency issues at this voltage with the controller?
What speed can I expect to reach in a 26" wheel at this voltage?

I don't have to worry about my battery current (6p milwaukee v28 (25.5v 16ah usable) in series with a konion 7s14p (25.5v, 20ah). I know the bafang won't handle really high current that well though, so I probably won't be going over 30a at 51v.

Knuckles isn't responding to my PM's, so if anyone else knows what price these go for (with one metal gear), that would be appreciated.

 

[TPA]

I think JohnRobHolmes still sells them at about $200 US for a stand alone motor.

http://holmeshobbies.com/home.php?cat=20

 

[tostino]

So I guess Knuckles sells them for a similar price? I'd want my motor to have one metal gear, so I don't turn them into peanut butter, and I know Knuckles has them.

 

[marks]

Knuckles isn't responding to my PM's, so if anyone else knows what price these go for (with one metal gear), that would be appreciated.

I sent him one a while back which he didn't respond to - I'm not sure if he knows he gets them?

I think JohnRobHolmes still sells them at about $200 US for a stand alone motor.
http://holmeshobbies.com/home.php?cat=20

*sigh* no listing for the fabled SWXB2
http://www.szbaf.com/en/product_detail.asp?ProductID=510

 

[TPA]

Knuckles is referring everyone to Keywin, even for the gears. If you contact Keywin, let us know how much he wants for one. If you can get a break on shipping for more than one, I might go in as well.

 

[marks]

Kewin doesn't list electric hub motors on his website/shop?

 

[TPA]

His website is not completed, may not ever be

He has a store on ebay, but will not sell the pricier items there because of the fees.

He has to be contacted directly for those.

I have avoided contacting him because the hub is a bit large, and shipping from China is high. If the shipping can be reduced then it would be worthwhile.

I've been considering the small motor from Goldenmotor, but the problem is the same there. $80 for a motor and $60 for shipping. (no break in shipping price for ordering more than one).

 

[icecube57]

So I guess Knuckles sells them for a similar price? I'd want my motor to have one metal gear, So I don't turn them into peanut butter, and I know Knuckles has them.

This probably has been done but I couldn't resist doing it again.

[youtube]s8MDNFaGfT4[/youtube]

 

[marks]

Does anyone know the cost of an SWXB2?

 

[tostino]

TPA, I am in Florida. What area are you in? If you wanted to, I am willing to go in with you on an order, and save on shipping (if it will be a savings that is).

Let me know what you want to do,
-Adam

 

[TPA]

I have not pursued ordering from Keywin for 2 reasons:

1. Ordering from a distributor in China usually does not net a discount for multiple items with regard to shipping. It can if you are ordering bulk from a manufacturer, but I have not seen it with a small time supplier. I have not tried Keywin to see if the same holds true with him.

2. School and work leave me little time to work on a bike right now, so it has not been a priority. If someone else was checking on it, I thought I would jump in, otherwise it will wait until May or so.

BTW I'm in Beaumont TX

 

[tostino]

I have not pursued ordering from Keywin for 2 reasons:

1. Ordering from a distributor in China usually does not net a discount for multiple items with regard to shipping. It can if you are ordering bulk from a manufacturer, but I have not seen it with a small time supplier. I have not tried Keywin to see if the same holds true with him.

2. School and work leave me little time to work on a bike right now, so it has not been a priority. If someone else was checking on it, I thought I would jump in, otherwise it will wait until May or so.

BTW I'm in Beaumont TX

Well I am checking in on it, and will see if I can get a discount on two motors shipped. If I can, i'll let you know.

 

[TPA]

Don't forget to consider the cost of relaying one to here, it will not be negligible.

What is special about the SWXB2.

 

[tostino]

Well for those interested, I got a quote from Keywin for $185 with shipping for a rear hub with metal gear.

Here is the return email

Hello Adam,
the old controller can not working with the geared motor at 48v,but you can upgrade the oscillation to 27 MHz, one metal gears and one SWXH motor total price is 185 usd included shipping by UPS,tHANK YOU.

Regards
Keywin

 

[TPA]

Did he cut you a deal for two (or more)?

 

[tostino]

Did he cut you a deal for two (or more)?

I replied asking about that, and am still waiting for a response. He never used to take days to get back to you =/...

 

[tostino]

Well i've had some trouble trying to get in contact with Keywin... He is taking 3-4 days to respond to my emails.

One thing I haven't found out yet, is what speed I can really expect to achieve with this motor (swxh) in a 24" wheel on 51v nominal.

I saw on Holme's site that 20mph is achievable at 36v in a 26" wheel, so that corresponds to 0.55 mph/v

At 51v in a 24" wheel, that would be 26mph.

25mph is really the slowest I want to go. I have all flat around me, and need to be able to make LONG trips with reasonable speed. Closer to 30mph is better... but I can't really boost my voltage without a lot of trouble.

Do you think 26mph is really going to be possible without pedaling? If it isn't, what motor would you guys suggest? I really am on a very tight budget, so it HAS to be less than $300.

Thanks,
-Adam

 

[TPA]

There are a couple of people here that could probably answer that better than I could, but from all that I have read, 26MPH on the Bafang will take some serious volts.

Try PMing Voicecoils, Russell (16mph at 36V 265lb total on flat ground...he also recorded 23.5mph at 46V), or Docnjoj (not an equal comparison, he has a tadpole trike).

Probably should have gotten one of those nine continents motors that ebikekit liquidated here last week.

 

[johnrobholmes]

i missed that sale!


26mph will greatly depend on the total weight and rolling resistance of the ride. If you are light, and have slicks on, It would take about 50 volts from my experience. Above that wind resistance really starts to get harsh, and you will also need a controller capable of limiting the amperage for hill climbing. High voltage on these little motors can smoke them quick with no amperage limiting. 36v 30a is what they are designed for.

 

[Russell]

There are a couple of people here that could probably answer that better than I could, but from all that I have read, 26MPH on the Bafang will take some serious volts.

Try PMing Voicecoils, Russell (16mph at 36V 265lb total on flat ground...he also recorded 23.5mph at 46V), or Docnjoj (not an equal comparison, he has a tadpole trike).

Probably should have gotten one of those nine continents motors that ebikekit liquidated here last week.

TPA,

That 23.5 @46V was the no load speed on a full charged 36V SLA pack plus a 6V SLA booster. On the road it delivered about 19 mph on its own with some assist available up to a bit over 20 mph. I top out at 16.5 mph on the 36V SLA pack alone with assist gone by 18 mph +/- depending on the SOC. The bike and I weigh in at about 265 lbs.

-R

 

[johnrobholmes]

And my 36v 20mph is with 12s 2p a123, probably a higher loaded voltage. Verified with a roadside radar.

 

[TPA]

Hey John, do you still stock bafang motors?

 

[johnrobholmes]

Just got in a few and sold them, I think I may have a front left. I will be getting more as my time allows for lacing.

 

[TPA]

Do you dish your rear wheel builds?

 

[johnrobholmes]

Yeah, just like any normal rear wheel build. They all get a bit of dish toward the drive side.