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[Sandor Lengyel]

Re: 1x9 or 1x10 gearing on a cargo bike (Yuba Mundo) with BBSHD/52V battery.

What's the max 1X gears I can run on a cargo bike with BBHSD/52V without snapping chains or destroying cassettes?

Yuba comes with 7-speed stock, but there aren't any higher end 7-speed shifters anymore. I'd like to upgrade to Shimano LX/XT quality shifter and wider range cassette (11-32 or 11-34), but that means a thinner chain. I live in a fairly hilly area. Reliability is key. I haul my 38 pound dog around and/or groceries and other cargo. Would like to upgrade the shifter/cassette/gears, but worried that the weight of the cargo bike with BBSHD will chew up drivetrains.

(FWIW, avid cyclists. We have a zillion bikes and strong mechanical skills. We run 1x11 on all our (non-electric) mountain bikes. Early adopter of e-bike motor. Running a geared drive on the Yuba since 2012 (when there were fewer options). Swapped to the BBHSD after we burnt out the motor gears on the Yuba.)

Thank you! WIll post pics of the Yuba conversion with some notes after I work out the quirks and bugs. (Easy install, but I forgot to order a speedo extension cable).

[paxtana]

Not placing blame or taking sides but I'm going to have to ask both of you to dial it back.
This question has been thoroughly answered which is fine, there's a difference of viewpoints which is also fine.
Now let's leave it be and it won't have to go any further.

[max_volt]

If the big bro to the 850 failed miserably why go backwards.

[paxtana]

Like I said, I am not taking sides, I am asking you guys to stop.
He was saying the wider the chain the stronger it is. And the one he used was wider than the one you used.
You were saying enhanced durability can be imparted from design or manufacturing processes.
Neither of you are wrong.
Unless someone has data from some sort of hydraulic pulling machine showing how much tension it takes to destroy each chain, these are just different approaches, different viewpoints, and a bit of miscommunication.

In any case this thread is for asking Luna Support questions, not for long drawn out arguments. As a manager at Luna if this sort of thing continues I will have to take action, and I don't want to have to do that. So please, both of you, calm down.

[paxtana]

In theory you could rework a 10spd so you keep the gear range while using few enough of the actual sprockets to change the spacing so it is spaced out for a 7spd chain.

https://electricbike.com/forum/forum...-drive-systems

Maybe even use the steel version of this chainring with its massive 42t granny gear

https://electricbike-blog.com/2016/0...-granny-munch/

So you would have a nice chainline and the strongest chain with your stock 7spd derailer..or maybe do the same thing but with modified spacing for use with a better derailer and 8 or 9 speed chain.

All this would involve modding the cassette of course.

[captaingeek@gmail.com]

Hi I received my order (42720) but its missing the thumb throttle. Also when I wire everything up, all i see flashing on the luna full color display dpc-18 is "waiting to load APP...". please advise.

[paxtana]

42720 does not show as a valid order#, I see no order associated with the email on your forum account either. Never seen waiting to load app, don't know what that's about. Anyway please email support with the order# on the email confirmation or printed packing slip.

[captaingeek@gmail.com]

43720 sorry...

[paxtana]

Can you take a pic?

[aiges]

Hi guys, I have a question regarding the crank arms for the bbshd. My problem is, as you can see on the pictures, that my motor can't be centered correctly into my bikes frame. Due to that fact the drive is mounted asymmetric. It wasn't possible to make it better, the chainring is damn close to the frame now. Couldn't get any closer. Also you can feel this issue while driving try freehanded. Is there a possibitliy to fix this? Are there any asymmetric cranks available? My bike is a Bergamont Deer Hunter Fatbike.
Thanks in advance for your reply.

[paxtana]

If you mean you want a drive side crankarm that's not offset outwards so much, yes the stock cranks should be a lot less offset than those. Did you try stock? The ones you are using say haibike on them, stock is just flat black.

[ebikeer]

I just bought a 52 volt advance charger and received an installed male xt60 instead of a female xt60 is this normal and how can this be fixed?

[paxtana]

It usually comes with an xt60 F-F adapter. Looks like this: https://lunacycle.com/xt60-female-to-female/
We can send you one if you want to give me your order#

[IIIRON]

So I bought a Luna fusion KHS late summer 2017. Its' got the 2500w option and the Luna Fusion 52v 17.5ah battery pack.

I did the whole balancing thing when I first got it (charge to 100% ride a few miles, charge to 100% about x5).

got about 300 miles on it.

So the issue (has always done this but only every so often under lower watts) is whenever the battery draw under load hits about a low of 46 or 47v the pack (longer hills) it will shut off and only unplugging and plugging back in will restart it. Typically at this point the display will show 54-54v or so under zero load and as low as 47-46v under full load level 6 or 100% throttle up a hill.

I thought packs only shut down around 42 or 43v? Or am I wrong? Should I try rebalancing it? Reset?

MERRY Christmas btw!

[Poco Askew]

You mean volts, not watts, right?: w=v?

[IIIRON]

@Poco Askew

Yes, sorry. Fixed post.

[ykick]

Seems fairly normal to me. In a perfectly balanced world the pack might possibly hit 40-42V under load. Trouble is, it’s not a perfect world within cell groups. And if you haven’t balanced in a while, by all means give it a good conditioning regime once again.

The other thing is that maybe it is touching 42V or so but the display simply doesn’t have enough refresh rate to catch that moment?

I would also suspect colder temperatures might be allowing more sag than in the warmer weather? Plus, you’re dealing with a Ludi yanking 50A peak so…. Gotta be a little gentler on things in the lower SOC regions, IMO. Thing about Li-ion/Lipoly is they can become very unstable and unpredictable at lower SOC.

Check the discharge curve graph made a few years ago using 8 series Lipoly groups:

Once things reach down around 3V/cell it’s obvious how things go over the cliff in unpredictable ways. But notice there's one group hitting 2.8V (ODDV cutoff on this BMS) while other groups are still close to 3.5V and nowhere near ODDV (over discharge detection voltage).

3V/cell multiply by 14S as in the 52V pack is about the point eBike battery pack BMS will shut things down.

Do a couple balance regimes. And try not to hammer the power at lower SOC. Particularly in colder weather. Otherwise the BMS is going to catch a cell group or two hitting 3V or less and shut it down.

[commuter ebikes]

"Try not to hammer the power at lower SOC. Particularly in colder weather". So true. Thanks for the tip.

[aiges]

paxtana
i tried the stock ones, no difference. It only looks like they have less offset but they don’t.

[paxtana]

Ok..well in any case there are plenty of alternatives that have no offset. My favorite is these: https://www.bike24.de/p1138455.html
But many models of unicycle cranks work as well. Or even using two left-hand cranks and loctite when you thread the pedal in on what would have been a reverse-threaded hole, see here for details https://electricbike.com/forum/forum...-duty-are-they

[IIIRON]

Seems fairly normal to me. In a perfectly balanced world the pack might possibly hit 40-42V under load. Trouble is, it’s not a perfect world within cell groups. And if you haven’t balanced in a while, by all means give it a good conditioning regime once again.

The other thing is that maybe it is touching 42V or so but the display simply doesn’t have enough refresh rate to catch that moment?

I would also suspect colder temperatures might be allowing more sag than in the warmer weather? Plus, you’re dealing with a Ludi yanking 50A peak so…. Gotta be a little gentler on things in the lower SOC regions, IMO. Thing about Li-ion/Lipoly is they can become very unstable and unpredictable at lower SOC.

Check the discharge curve graph made a few years ago using 8 series Lipoly groups:

Once things reach down around 3V/cell it’s obvious how things go over the cliff in unpredictable ways. But notice there's one group hitting 2.8V (ODDV cutoff on this BMS) while other groups are still close to 3.5V and nowhere near ODDV (over discharge detection voltage).

3V/cell multiply by 14S as in the 52V pack is about the point eBike battery pack BMS will shut things down.

Do a couple balance regimes. And try not to hammer the power at lower SOC. Particularly in colder weather. Otherwise the BMS is going to catch a cell group or two hitting 3V or less and shut it down.

Thank YOU sir.

I will try a rebalance and try to keep from hammering once its under 55v (no load) or so. It is a bit cooler but did it in warmwe weather also.

Had some fun in the snow today though :)

[fos'l]

I attempted to charge my 52V, 10 a-h Luna battery with your 3 amp charger which worked fine yesterday when charging my 52V, 6 a-h battery. The red and green lights on the charger came on, but stayed on when I connected the XT-60's on the battery and charger and there was no sign the charger was operating. The fuse (5 amps, I think) is fine. Does this mean that my charger is dead?

[fos'l]

It charged the smaller battery yesterday, but wouldn't charge the larger battery today. I checked the charger and its output is 58.4V. There is slight greenish corrosion on one of the XT-60 "male" leads for charging the battery. Could the slight corrosion be the problem, even though it didn't affect the voltage reading?

[paxtana]

Maybe. I would try charging the smaller battery and see if it makes any difference but there definitely should not be corrosion on the xt60. Also, gold plated connectors do not corrode easily so you may want to evaluate how that got there in the first place..

[fos'l]

Thank you for your response. The XT-60 connector on the battery got wet and was inside the cellophane "bag". That's how it corroded AFAICT. I have a spare XT-60 with a pigtail which I'll replace the connector with and see if that solves the problem. If not, I'll use the 6 a-h battery and see what happens when I try to charge it.

UPDATE: Replaced the XT-60 connector on the battery and problem resolved. Funny what a tinge of corrosion can do.

[Downshift100]

I have a Gravity Bullseye Monster LTD fatty…. The bottom bracket size is 103mm.......I need to know exact spindle length (width) of threads on 100mm BBSHD. If possible I would like to get 100mm HD instead of having to make up the difference with spacers on 120. Looking for the best chainline. With the 100 could I still get gray nut and black nut on without having any problems?

[paxtana]

A few mm over is fine. Worst case scenario you just do without the black lockring which acts as a jam nut. Then just use a dab of Loctite instead.

[pschuepp]

Dear Luna, I just received my order #43737 and installed this storm controller 20A black with LCD dashboard for hot rod programmed KT-LCD3 on my FAT X 7 speed Sondors bike. After power on and press i button I do not get LCD light up or power, nothing. Then I plugged in the Sondors LCD and power on and it lights up, reads numbers, battery level, pedal assist level, but no power....when I turn on throttle I get an ERROR 30. THere are two red wire connections, with no instructions, so I tried to switch them and got same results. Everything else connects logically to replace the old controller. Help please. Paul Schuepp 603 203 8317
pschuepp@gmail.com

[Poco Askew]

I have a Gravity Bullseye Monster LTD fatty…. The bottom bracket size is 103mm.......I need to know exact spindle length (width) of threads on 100mm BBSHD. If possible I would like to get 100mm HD instead of having to make up the difference with spacers on 120. Looking for the best chainline. With the 100 could I still get gray nut and black nut on without having any problems?

How bout the 110mm BBSHD? That would certainly fit but not need a lot of spacers while giving you a little fudge room, if needed.

[ykick]

I've heard Bafang makes other sizes possibly 110mm? Luna doesn't carry them AFAIK...

[Poco Askew]

They do (or did). I think Luna has had them, but not often from what I 've seen.
If you look at the BBSHD manual you will see 68mm, 100mm, 110mm and 120mm models.

[Downshift100]

I think that's what I need. I'll have to try and find out if anyone has them in stock.....Thanks for the info

[pschuepp]

Update Luna to post #763. When I put the Luna LCD back, and turned out this time it did light up. Pedal assist seems to work, 0 turns off power, 1-5 all seem the same on the bike stand turning the crank. Max speed I am getting is 26.3 mph (thought it might go to 30?) Battery level read out works. But now my throttle does not work at all. Checked the connections again seem fine. ???

[HIGHVOLTAGE]

What kind of Sondors bike are you using? The Original or the X?

[pschuepp]

I have the FAT X 7 spd model. So perhaps the Luna 20A controller is not set up for the new X throttle,which does not have an on/off switch. I ordered from Sondors the orginal throttle with the on off switch and LEDs for $65. I hope that works. Will let you know.

[aiges]

paxtana
Nice, I´ll get them a try. Order is placed, I´ll give you a feedback. Hopefully this will solve the issue.