Super hiryuu - A BBS02 / Leafmotor / MXUS 3kW Dual sus. bike

neptronix

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Been a while since you've seen a build thread from me.. in the meantime i've had various health freakouts and lost almost 90lbs on a keto diet and have been thinking about going lower power due to my body just needing less power to move nowadays. I also live in an extremely hilly area now, too.

I've got a 750W bafang BBS02 coming in the mail in a few days and a Turner O2 full suspension bike with a nice and fairly open triangle, ready to be stuffed with batteries... :)

The goals for this project:
1) Tune suspension so that it can handle off road and on-road and be general purpose for off road and on road.
2) Investigate what kind of thermal envelope the 750W 48V BBS02 has and see if it has more headroom to take advantage of.
3) Investigate whether running an external controller increases this headroom and find out by how much.
4) Add some kind of heatsink or cooling medium ( if possible ) and see if the thermal headroom improves.
5) Max out the power and see what a BBS02 is really capable of, and find out what it can tolerate.

Stay tuned!

Major update!
Through my testing, i found that the BBS02 isn't really capable of any more power over stock, and the width of the bottom bracket made pedaling uncomfortable and a little painful for me. So i have gone back to a hubmotor for this build, using the newer ~90% efficient leaf 1500w motor. The talk about the Leaf hub motor starts on page 3.
 
Interesting!
Will follow this build for sure.
Maby you should change the last centence in your signature during this bild :wink:
 
I'm excited.. I've got a 29er ready for the magic pie be be bolted into it, but it's just been collecting dust... but it's the bafang that gets me hot and bothered honestly, i haven't been so excited about building an ebike since i was in 2011 when i really got started. There's gonna be as much love put into this build as i did with my MAC ride long ago :)

I feel like this is a big evolution. If you think about it, all motorcycles are generally mid drive + dual suspension because that's just the best and most functional setup.

Pics tomorrow :)
 
Ehh.. okay, i don't have anything to show off yet. DHL arrived late and i had a bunch of work to do. But i got the motor and accessories fitted. Tomorrow i get to do all the cabling. I'm building this all up from a bare frame, after all.

I got some weight measurement of the bafang BBS02 motor + controller unit. It's 9lbs, 1oz, or 4.1kg.
Considering that it replaces the bottom bracket, which is about 0.5lb, it adds about 8.5lbs to the bike, which isn't too bad.

Well, it did deliver on the promise of being lighter than the MAC, so that's a good start.
 
Hi nep,

I have followed closely most of your builds. Until the end of July I have been a lurk in ES :p.

I decided to go with bbs02(9fet) in my 1st build after some hick ups. Got some 6s 5ah lipos (12s1p). The end result is great fun and the 28" skinny tire steel framed road bike ensures great efficiency (not tested yet) but estimated to be around 25-30 km.

I'm waiting eagerly to see how the bbs02 works with the fully of yours

Also mapping the corner points of the newer bbs02 is interesting as well.
 
neptronix said:
I got some weight measurement of the bafang BBS02 motor + controller unit. It's 9lbs, 1oz, or 4.1kg.
Considering that it replaces the bottom bracket, which is about 0.5lb, it adds about 8.5lbs to the bike, which isn't too bad.

Do you know the weight of the entire package; motor, controller, chainring, crank arms, cables and all hardware?

-R
 
Nice to see someone thrash one of these. The stock unit doesn't excite me at all offroad.
 
Sorry, i don't have the exact weight of everything. Other than the motor unit, everything is pretty darn weight optimized ( chainring, cranks, etc ).

Anyway, the bike has had the cables run, it's wired up, i just have a battery plate that has some primer on it drying overnight. It'll get hit with a few layers of black paint, bolted up, em3ev bag strapped on, and it's go time tomorrow.

It just took a bit longer than i thought to make the battery plate that protects the frame bag from hitting the shock..
 
I think your limiting factors will be the reduction gear's ability to take much more power and probably overheating that little motor. I have three bikes setup with the bbs02 motors and they are great units set up as they are intended to be.
I don't think they will take well to being hot rodded, but I am anxious like others to find out! Hopefully I am wrong!
 
Damnit, another day of watching paint dry, lol.

hiryuu01.jpg


Motor unit alone: 9lbs, 1oz

hiryuu02.jpg


Cheapy shimano bottom bracket that it replaces, 11oz.

hiryuu03.jpg


I got desperate and made a ghetto cycle analyst mount out of a flashlight mount because i destroyed he last one in the big crash..

hiryuu04.jpg


The bike so far.. awaiting the plates.
 
You are installing a cycle analyst? In addition to the Bafang Display?
What type of battery & voltage are you planning?
 
It has both, and will also have two temp sensors, preferably one on the controller side and one on the motor side to determine if there is extra thermal headroom gained in taking the controller off.

Gonna be lots of crap on the handlebars, lol.
 
OK! Some motion, finally :)

hiryuu05.jpg


hiryuu06.jpg


hiryuu07.jpg


Battery proctor plate is complete.. :)

hiryuu08.jpg


The final result.. although i need to tune the seat height, shock air, handlebar angle etc etc.

I suppose i have some disappointing news. With some abuse, we saw the motor hit 140f on the stator side, or 62C at the case. Inside it is most likely much hotter than that. This is on stock settings riding at full power on mostly full gear.

Already kinda discouraged by the amount of heat it produces on stock power. I ran it on a saggy 12S 15AH hobbyking pack.

Okay, one odd thing, i saw the amps jump all the way up to 34A more than once. Somestimes it would hit 29a.. but usually hung out at 20-25A. This controller is not well behaved by any means.. if you are in the wrong gear, it will also give you a bad case of 'the shakes' at the bottom bracket ( the motor is just cogging slowly ).

Overall i am not impressed with the PAS at all. You'd have to constantly hit the brakes between gear changes to prevent it from chewing up the rear gears between shifts. There is a ~1 second delay after the PAS sees motion in the cranks and when it delivers power. There is also a 1 second delay before it turns off when you stop pedaling. This is really annoying. This discourages you shifting between gears...

I'm definitely going with an external controller. I shouldn't be seeing 34A at low cadence, ( that may very well just be saturating the stator which is part of the heat problem ) or even 29A.

Very possible that i have the wrong gearing as well. I will have to investigate and tune this bike proper, it's rather rough at the moment, but the battery plate worked, which is excellent news. Having full suspension on an ebike for the first time is a dream too!

hiryuu09.jpg


I gave my neighbor his first ride on an ebike and he was about as thrilled as they get! I remember my first ride, it was a 250w bionx kit in 2009 or so. I thought it was cool.. lol. The look on his face was priceless.
 
neptronix said:
Overall i am not impressed with the PAS at all. You'd have to constantly hit the brakes between gear changes to prevent it from chewing up the rear gears between shifts. There is a ~1 second delay after the PAS sees motion in the cranks and when it delivers power. There is also a 1 second delay before it turns off when you stop pedaling. This is really annoying. This discourages you shifting between gears...

kepler has been working on a solution to this.

He's running PAS with a turbo button instead of graduated throttle. He's also using the throttle plug for gear changes - throttle application cuts PAS immediately, and PAS picks up with much less delay vs brake cut out switching.

My kit is showing up tomorrow - I am running one of these



http://www.ebay.com/itm/Moose-Billet-Kill-Switch-7-8-Red-/390919148205?pt=Motorcycles_Parts_Accessories&hash=item5b0498d2ad&vxp=mtr


and plan on wiring it to the throttle plug in order to reduce or eliminate delay/lag between shifts....

No throttle planned for the lead sled

Len
 
Interesting.
Can one just disable the PAS?
Does it involve ripping out a sensor, or is there more of a civil way to do it?
 
neptronix said:
Interesting.
Can one just disable the PAS?
Does it involve ripping out a sensor, or is there more of a civil way to do it?

From what I am learning, the PAS function can be disabled one of two ways:

1. Setting PAS to 0, assuming the controller's profile was originally programmed to be %100 throttle when PAS is set to 0
2. Getting a controller cable and re-setting the profiles your self.....


I have a post over on the "programming the BBS...." thread since I should see my kit tomorrow...

Len
 
Okay, em3ev kit here and i get no throttle when the assist level is set to 0, sadly.
Paul says that they're programmed to run on throttle with the assist level set to 0, but that's not happening for me.

My battery was low, so i don't know if that would make a difference.

Might just rip out the controller and rewire the whole thing to just run with a cycle analyst and 3077 9FET. I doubt that i can turn this ho of a controller into a housewife.

If i get rid of PAS and go back to throttle, i am going to want cruise control and a twist shifter again anyway.

Gonna ride it a bit on stock power, get some videos and measurements first tho.
 
I'd love to see what the motor can do on 16S & 35+ Amps with a custom controller.

My suspicion is that it will still generate a LOT of heat, even without the integrated controller...
 
teslanv said:
I'd love to see what the motor can do on 16S & 35+ Amps with a custom controller.

My suspicion is that it will still generate a LOT of heat, even without the integrated controller...
Me too~ But, I suspect it will need at least some cyclone style cooling fins. :?
 
My testing so far says that 48v and 20 amps is about max for reliability... it gets hot but not to " self destruct " levels.

So, bottom line, pushing more than this is a waste of time.

Harsh shifting is easily fixed by a few hours of seat time, once you get the hang of backing off the throttle, shift, ( while chain is still moving, but not under heavy load ) throttle.. all is well.. no need for gimicks.

Throttle on the BBS sucks. it's almost on/off .. a CA v.3 properly programmed is the way to go imo.
 
The problems mentioned above have been well documented over the past 12 months. Unfortunately the main thread is so big now, it difficult pick out all the useful stuff.

Most of the bad behaviour can be tuned out with re programming including turning the throttle for nice linear control. Most of this information can be found in the programming thread.

In relation to harsh shifting with PAS, a light dab of throttle kills PAS power and allows you to shift smoothly and quickly. Just take a little bit of practice. Or you can automate it like I have done with a throttle hack and microswitch arrangement off the gear selector. Again all documented in the main thread.
 
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