Wheel building for hub motors.

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the 175x2mm spokes arrived yesterday, i measured them at 175mm on my rule by hanging the j off the zero mark of the rule.

spent a productive 75minutes lacing the wheel in one easy go.. (the spoke as an insertion tool tip- pure genius- )

having a sit n sup atm Sunday afternoon etc... and will try to true the wheel in the up ended frame using cable tie markers later, Not for use but to check a) my ability, and b) the length if any of spoke protruding from the nipple end or laving mms of thread when taught. as to properly size the 14g spokes ..

 

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I am a newbie 2 months in and change, though no stranger to two wheels, a year of arduous commuting mid 90's put me off 2 wheel transport for a while, but a noname el cheapo cycle is generally at hand for local light shopping trips and summer visits to riverside pubs. bdlc motors and lithium batteries are familiar to me from dabbling with rc though these days i just lurk on forums and watch vids..

The above wheel is part of a bundle dropped off by a pal wanting to free some room in his own yard of residue left behind by sons who have left home.. I mentioned my 'new' ebike and it was 'oh u like ebikes u want some??'

I converted my 'daily ride' cycle after pondering too long on trips of a certain distance, not being as young or quite as active as i have been I was considering alternatives when i should have been cycling.. so the ebike conversion of my step through shopping bike took place..
So thats ebike #1, in need of new brake blocks for the first time in 4 years, see how the brake block residue has stained my nice cream coloured tyres.
ebike #2 one of the freebies, is an amazon 699 special ebike with some great design features like holes in the top of the bars for cable runthrough and catching rain to gather at the bottom bracket, and rear stays that require wedges to open wide enough for the back wheel to fit. (i checked its the stock freewheel fitted, and the wheel itself is pretty unique)
Beyond bike bits about £60s worth cables, bottom bracket, brake pads,chain, the 'e' aspect required a new kt controller and headset,
this bike was expensive to get roadworthy and the gears took ages to soak in oil and free up from the seized position, i failed to get the front changer to stretch over the 3 chainrings so it only selects between the 2 larger drives.

Both the above are eu/uk street legal 250w limited to 15.5mph etc..

and ebike #3, well i had to drop the motor with the 'wrong' spokes in the frame to test excuse the gaffer tape and old travel toilet bag controller enclosure. I had invested in an extra large ebike controller box from those nice folk over at aliexpress, No way was the 28a controller and excess wiring going to fit.

this is a 500/750/1000?w motor the controller headset is cracked and the display is useless. Plans for this bike are vague atm it was more of a challenge to get it up with the seized bottom bracket (yeah 2 bikes with seized bottom brackets) and completely destroyed back wheel. Its brakes need a complete overhaul the rear caliper attempts to bend the rotor/disk atm!! and the cables are far from pristine, My neighbor who drives some evenings for food delivery services has been interested in this bike for some reason..





So lots still to do with this bike but knowing that once all together it will work well is very nice to know.. so far i had only spun the motor up once in the garage vice and that was not fun..

 

[calab]

I tend to place the hub motor on to a bucket where the hub cover rests on the bucket, it sits level because the axle shaft is not interfering like when I just laced it on the table.

Do you put all the spokes in loosely then lace or do you just put in one flange of spokes or do it 1 or 2 spokes at a time?

 

[Chalo]

I tend to place the hub motor on to a bucket where the hub cover rests on the bucket, it sits level because the axle shaft is not interfering like when I just laced it on the table.

I do it that way, but in my lap.

Do you put all the spokes in loosely then lace or do you just put in one flange of spokes or do it 1 or 2 spokes at a time?

I put in 9 at a time: right side leading, then left side leading, then right side trailing, then left side trailing. I've had co-workers who make a 36 spoke hairball first, but that looks like a nuisance to me.

 

[D Alan Stewart]

Use 2mm stainless steel washers on the spoke heads, 4mm washers or nipple washers at the rim if necessary.

So substituting stainless steel washers for brass should solve my problem? I’m building my first wheel, used the Grin Technologies spoke calculator, and was very surprised when my 14g spoke heads could pass through the spoke holes in my hub motor. They seem to be nearly 4mm in diameter. So I bought brass washers, successfully laced the wheel, then discovered the pictured washers equally tightening all the spokes as described below.

I first tightened all nipples to where the threads were just hidden. I’m was surprised that once tightened to that degree all spokes were still loose and the spoke nipples were not seated against the rim. There was probably an average of 2mm or more play, so I went around the rim tightening each nipple by one full turn. I think I did that three times, now some of the nipples are seating and starting to develop some tension in the spokes. Does this sound right, or am I likely to need washers at the nipple end also?

The rim is 24” and the Leafbike hub motor is reputedly 241mm in diameter.




Thanks for any help.
Alan

 

[Chalo]

So substituting stainless steel washers for brass should solve my problem? I’m building my first wheel, used the Grin Technologies spoke calculator, and was very surprised when my 14g spoke heads could pass through the spoke holes in my hub motor. They seem to be nearly 4mm in diameter. So I bought brass washers, successfully laced the wheel, then discovered the pictured washers equally tightening all the spokes as described below.

I first tightened all nipples to where the threads were just hidden. I’m was surprised that once tightened to that degree all spokes were still loose and the spoke nipples were not seated against the rim. There was probably an average of 2mm or more play, so I went around the rim tightening each nipple by one full turn. I think I did that three times, now some of the nipples are seating and starting to develop some tension in the spokes. Does this sound right, or am I likely to need washers at the nipple end also?

The rim is 24” and the Leafbike hub motor is reputedly 241mm in diameter.

View attachment 342775
View attachment 342774

Thanks for any help.
Alan

Those holes are so big that it might be better to use 2.5mm stainless washers, with or without 13-14ga single butted spokes to fill them better.

Whether you need nipple washers is a function of the holes in the rim, not those in the hub. If you're reusing a rim that was originally laced to a hub motor with 12ga spokes, you will need nipple washers. If you're using a bicycle rim that presumes the use of 14ga spokes, then you won't need nipple washers (but you can still use them to take up excess spoke length, if that's an issue).

 

[D Alan Stewart]

Those holes are so big that it might be better to use 2.5mm stainless washers, with or without 13-14ga single butted spokes to fill them better.

Whether you need nipple washers is a function of the holes in the rim, not those in the hub. If you're reusing a rim that was originally laced to a hub motor with 12ga spokes, you will need nipple washers. If you're using a bicycle rim that presumes the use of 14ga spokes, then you won't need nipple washers (but you can still use them to take up excess spoke length, if that's an issue).

Thanks so much!
Alan