Kit arrived from BMS

[Mattjenkins1990]

Some issues with it, they have not put a rim and spokes on the q128h. Looks as if the wheel is actually a 22inch rim, reckon i am best trying to get someone to fit the rim and spokes or do it myself. Any idea on spoke length required

Cableing seems ok however the cable from the motor is not clear and there is no instructions. Are there any out there

Cheers

Matt

 

[Deleted member 4366]

It would help if you told us what you ordered.

 

[Mattjenkins1990]

I got a q128h motor wheel, should have come assembled but just the hub has come. I am considering options as to whether to buy the spokes 240mm i think seems about right or getting someone to build the wheel for me. Any thoughts regarding this ?

I have started assembling the rest, i drilled a hole and put the speed sensor in soldered the red to the motherboard and connected the black and white to wires that are already there. I did cut the bottom black of the two and the white and connected them what were these used for before they were cut ?

The bottle is a 09 48v 11.6ah as part of the kit with the accessories.

I have assembled the handlebars LCD, Brakes, Gears, throttle and buttons, plugged them into the controller then tried plugging the motor in turning it on and seeing if i could make the motor turn (although its not in the wheel yet) but it doesn't seem to be working. I am concerned that perhaps i killed the controller soldering the speed sensor in. The speed sensor is on the inside of the front forks but when the wheel turns no speed is relayed to the LCD unit. I can see the throttle spinning when i run it up but no motor revolutions.

 

[Mattjenkins1990]

on a side note i was connecting the motor directly to the controller output, i have this additional cable with 3 thick cables (green blue yellow) and 6 thinner cables is this part of the motor cable setup ?

 

[trex]

can you post some pictures of what you've received? you only need to connect battery, controller, LCD and throttle to test the motor. Speed sensor, PAS and brake levers can be left for later.
The 5 or 6 way cable is for the Hall sensors.

 

[Deleted member 4366]

You can connect the motor directly to the controller. The other cavlea are to extend the length for your one, and to convert other motor connectors to your type. You won't need the latter, though you can cut off the connectors and use it as an exact length converter if you cut off the notor connector and join the wires.

When you cut the black wire in the controller, did you join all three ends?

Did you cut the correct white wire? One is used for the speed sensor from the motor, but the other is for the throttle.

 

[Mattjenkins1990]

I didnt connect the third wire no i was under the impression i didnt need too.

 

[Mattjenkins1990]

reconnected the black and can get the motor turning now., do i need to do anything on the LCD to get speed sensor working ?

Do i need to reconnect the white that was there also ?

Would you guys recommend getting a pro to do the wheel building or is it something relatively simple to do yourself ?

 

[trex]

it takes about 1 1/2 to 2 hours to build a motor wheel, quicker than trying to find someone to do it for you. d8veh may tell you the correct length for your spokes, I reckon it's about 220mm-223mm for 26" rim.

 

[Deleted member 4366]

reconnected the black and can get the motor turning now., do i need to do anything on the LCD to get speed sensor working ?

Do i need to reconnect the white that was there also ?

Would you guys recommend getting a pro to do the wheel building or is it something relatively simple to do yourself ?

I can't understand what youve done or undone. Perhaps a photo and an explanation of the current status would help.
The speed sensor can't work without the wheel magnet rotating.

 

[Mattjenkins1990]

Sure, I have put the magnet on the spokes. I will take some pictures this morning and get them up. D8veh do you have any idea what spoke length I need if I am to try building a 26 inch wheel. The inside diameter of the rim is 22 inches

 

[Deleted member 4366]

The spoke length depends on the ERD of the rim. Every rim is different. You need to measure the inside diameter of the rim to the nearest millimetre. Measure in two directions and take the average. Add on 5mm to get the ERD.

 

[Mattjenkins1990]

Ok i have taken some pictures as promised


I have mounted everything to the handle bars and that all seems to be working correctly as its all plug and play which was nice.

Fitted the speed sensor and magnet onto the front wheel. The magnet is pointing inwards. This still isn't working. To connect this i have soldered it to the controller by drilling a hole in the battery casing. The picture included shows where the cable comes through and where the three wires have been connected.

The Red i have simply wrapped together with the other Red and soldered to the PCB point

The White i have cut and joined the new wire with the one coming out of the PCB

The Black i have connected all three cables.

At present when i connect the q128h motor up i can make it spin but only using assist setting 5,. When i spin the front wheel i still see 0mph on the LCD and everything else is 0's

As for the motor cables themselves the q128 has a 9 pin male adaptor, this fits straight into the controller however the cable is not long enough.

There is another cable included which is a 9 pin female to 3 thick (Yellow,Blue,Green)6 thin ~(Red,Black,Blue, Green, White, Yellow). No other cables that look to be motor related. I am not sure if this is used to connect the motor and controller.

In relation to measuring the inner diameter i believe it is 520mm so a 525mm ERD ?

Many Thanks for your replys

Matt

 

[Mattjenkins1990]

Just re-tested the speed sensor and its working ... hurrah

 

[Deleted member 4366]

You need to be sure and precise with your ERD measurement. I used one of those Rigida 26" rims with the blue label from Ebay. I measured the ERD as 528mm. The spokes calculate as 219mm for a 2-cross pattern. If yours is 525mm, the spokes would be 217.3mm ), so anything from 217 to 220 should be OK if you have a double-walled rim, which I guess it is since it's deeper than mine. For 1-cross, it's 203.5mm, so up to 205mm should be good. I prefer the 2-cross lacing. I don't know why, but something in me says it should be better for a high torque motor, plus the longer spokes are more elastic (slightly), so the spokes won't loosen so easily.

I'm glad you've got it all working now. It's very satisfying when you do a hack and it works.

Did you fit the pedal sensor. If so, does it work OK.

Could I see a photo of it, especially the actual sensor even if you didn't fit it? I need to get one because the one I got on my last controller doesn't work. I'm sure it's different to the one I got with the kit like yours, but I don't have that bike anymore to compare it.

 

[Mattjenkins1990]

Cheers for the reply. I did a quick calculation myself and got a different spoke length. I think the ones that are on there now seem to be around 260mm so i am unsure. The spoke tray is about 10mm and the rim depth is around 20mm.

The PAS that i got was the one with the RED magnet attached a photo. I have not fitted it as yet, getting the tool to get the Pedal arms off is also on my list.

My Final concern is still with connecting the motor to the controller. I need about another 30 - 35cm of cable ton connect the two and have not the foggiest how to wire it using the 6 by 3 cable provided

 

[Deleted member 4366]

Thanks for the photo. That sensor is the one I had, so the controller must be faulty.

In your dpoke calculation, you've got the wrong number of spokes. It should be 36 not 22.

 

[Deleted member 4366]

With my kit, I got a 1m extension piece with a male and female 9-pin connector on the ends. It's too long, but it works if you don't want to cut and join.

Additionally, I got a 1m adapter wire that had the motor connector on one end and bullets on the phase wire and a block connector on the hall wires at the other end. I cut the connector off the controller and the bullets and block off the adapter lead, adjusted the length and joined them together by soldering the ends and heat-shrinking them. Alternatively, you could cut and shorten the extension lead, but that would mean one extra connector in the line.

 

[Mattjenkins1990]

OK thanks. That makes sense, although my rim seems to have 32 spokes. Does that mean the motor will not fit in this rim ?

I did not get this male female 9 pin extension lead, do you know if they are available to buy anywhere ? It would make life quite a bit easier than fabricating my own

 

[jonathan75]

I tried building a wheel and think it's well worth paying someone to do it for you. I paid 25 plus 13 for the spokes for a master wheel builder to do it and it's a great build. You're owed that cost by BMS incidentally - I suggest you contact them and tell them they sent the wrong product and ask them to please put things right. There is a reason people pay a lot extra for a motor wheel.