Recommendations for a rim

Remember XC is lightweight guys on lightweight bikes doing a lot of climbing under purely human power. A situation where weight is very important. This stated, despite the importance of lightweight in XC racing, the trend of these riders is moving away from the narrower rims of the past and towards 30mm inner width on a very slightly wider tire, perhaps 58mm.

OP's situation is quite different than an XC rider in that he is not a lightweight rider. OP is a heavier rider (at least I get the impression he is) on a heavy cargo ebike that he needs to carry 50 lbs cargo and might even carry another passenger therefore I would not base my decision on what XC racers use for equipment.

Sure a 24mm inner width rim is compatible (though not optimal) with a 55mm tire according to the chart but I wouldn't never want to use 24mm for the OP's application given equal quality rims in narrow vs. medium width.

P.S. For those who didn't clink on the link or look at the chart 19mm to 24mm is considered compatible but not optimal for a 55mm tire. Same goes for a 36mm to 40mm internal width rim. Optimal width for 55mm wide tire is 25mm to 35mm internal width according to the chart.

Again, the tire to rim ratio is competely overblown.

Do you really think anything bad is going to happen if the rim is 24mm instead of 25mm. Sometimes 1mm really does make a big difference. In other areas of the bike. But not for this. People ride old 19mm ZAC rims laced to hub drives all the time, there are probably 100,000 of them out there doing it weekly. Even Luna and Grin ONLY offer the old skinny rims to lace hub drives to. Which is personally irritating to me (for tubeless reasons, not for rim width) but on pavement it's not an issue. Worst thing that happens is they get a flat tire because the rim isn't setup for tubeless.

The manufacturers 'recommend' a wider rim. Why? Wider rims are newer, so they can sell you one, so they make money. Just like Boost 148mm frames are now the standard, so that if you believe the hype, you have to now spend thousands of dollars converting over to the new standard. A few years from now they will come up with some other recommended 'standard' so that they can sell new products. That's how this industry works by the way. The bike industry is hurting a lot more than you may think. They waited two years for components during Covid, overordered many items, and now are desperate to unload merchandise in stock. Spamming some tire / rim compatibility chart is a cheap way for them to market stuff that's now piled up in their warehouses.
 
Do you really think anything bad is going to happen if the rim is 24mm instead of 25mm.

The manufacturers 'recommend' a wider rim. Why? Wider rims are newer, so they can sell you one, so they make money. Just like Boost 148mm frames are now the standard, so that if you believe the hype, you have to now spend thousands of dollars converting over to the new standard. A few years from now they will come up with some other recommended 'standard' so that they can sell new products. That's how this industry works by the way. The bike industry is hurting a lot more than you may think. They waited two years for components during Covid, overordered many items, and now are desperate to unload merchandise in stock. Spamming some tire / rim compatibility chart is a cheap way for them to market stuff that's now piled up in their warehouses.
1. No I don't think a 25mm internal width rim would be much better than 24mm. But why would I use the low end of optimal anyway? 30mm internal width is a much better starting place if the optimal range spans 25mm to 35mm.

2. Increasing the rim width to tire width ratio is not a fad. The road bike industry figured this out a long long time ago and hasn't looked back. The same thing is happening in mountain bike.

P.S. Don't forget we are talking about a heavy cargo ebike here and not a lightweight human powered racer. Also you claim lots of hub motors have been laced to 19" inner width rims but what does that have to do with our argument when you don't keep track of the tire size. No doubt many of those 19" inner width rims are running tires much skinner than 55mm (street tires for 26" can be found narrow as 1" and widths up to 1.5" are very common for 26"). This especially as hub motors are more likely to be used on the street than they are in the dirt.
 
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How much do you weigh?
Im 160. Not heavy. Crap hit another pot hole today hard and broke another spoke. It's a pain to change spokes all the time, but I have so many spare 12G spokes from my other build. I just keep changing spokes. What rim do you recommend and can YOU LINK TO IT? WEB LINK?
 
Im 160. Not heavy. Crap hit another pot hole today hard and broke another spoke. It's a pain to change spokes all the time, but I have so many spare 12G spokes from my other build. I just keep changing spokes. What rim do you recommend and can YOU LINK TO IT? WEB LINK?

I would go with this one:


You have at least two options for that rim:

1. Use 11 gauge or 12 guage spokes. (Husky is successful using these thick spokes with this rim (even in rental fleets) because the wheels are handbuilt in the USA. Example: BICYCLE WHEEL 26x2.125 Front Alloy Double Wall 12G )

Note: Stress relieving a 12 guage spoke takes a lot more hand force than stress relieving a 14 guage spoke.

2. Use the large spoke hole opening of the Husky rim with a washer for thinner spokes like 13 guage or 14 guage. This has the advantage of helping improve the spoke entry angle into the nipple which with a rim drilled for 14 guage spokes would be around 76 degrees for a typical 26" rim using 1 cross lacing and a Direct drive hub motor with the usual PCD of 232mm. The same set-up using 2 cross lacing works out to be 67 degrees and 3 cross works out to be 65 degrees. Ideally you want a spoke entry angle of 81 degrees or greater to reduce stress on the thread end of the spoke.

P.S. How do you use the pedal drive train on your ebike? Are you a smooth spinner the vast majority of the time? Or do you mash a lot? How much does your pedaling style change when carrying a passenger? This is a very important question because pedaling is another thing that can contribute to spoke loosening on the rear wheel.
 
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A great article on butted spokes for those of you who haven't read "The Bicycle Wheel" by Jobst Brandt:


The reason why butted spokes see lower stresses at the ends is because more flexible spokes share load between neighboring spokes more easily. Perhaps you have a "rigid" friend or co-worker who has trouble sharing work or asking for help because they need things to be done their way. Perhaps if they were a little more "flexible," they would have an easier time sharing the load.

The extent to which load is shared between neighboring spokes depends on the ratio between the rim stiffness and the spoke stiffness. In engineering terms, this ratio (actually, the 1/4th power of this ratio) is called the "characteristic length." The higher the rim stiffness, the more spokes will share the load. The higher the spoke stiffness, the fewer spokes will share the load.

Speaking of stiff rims this one I am linking below would have been perfect for your cargo ebike:


It's got 29mm internal width, rim brake compatible, shader valve and the ability to order custom spoke hole angles for use with large diameter flange ebike hub motors.
Develop to stand loads up to 180kg, its thick nipple bed allows big drilling angles, perfect to be used with electric hubs.

Too bad it is not available in 26" size.
 
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Will you have to drill out the spoke holes on the rim?

Sapim Polymax nipples work at greater angles then standard nipples.

This post has a picture that shows it well.

You could also get nipples with a bigger head that could accept normal spoke gauge, Holmes Hobby used to sell them. No more.
 
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Will you have to drill out the spoke holes on the rim?

Sapim Polymax nipples work at greater angles then standard nipples.

This post has a picture that shows it well.

You could also get nipples with a bigger head that could accept normal spoke gauge, Holmes Hobby used to sell them. No more.
That wheel you linked is a 24" so the spoke angle would be steeper at around 74 degrees for a 1 cross compared to being 76 degrees for a 1 cross on a 26" rim (which the OP is using).

Still the picture you posted is a good example of how despite the use of Sapim polyax nipples (which have a rounded head which acts like a ball joint and allows for some pivoting) there is still a good amount of bend on the spoke where it is entering the nipple.

Not sure what OP is gonna do but I see Sapim claims their MG nipple washer complements their polyax nipple while at the same time strengthening the rim.

See attached picture of the Sapim MG washer and Sapim polyax nipple working together.
 

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Showed that pic as an extreme example only. Once the angle is too much you have to go to radial lacing or drill out the rim holes.
It doesnt matter if its 24 or 26 rim, with big hubs like my Leaf and 26, the angle is not as extreme between the nipple and spoke but I still notice it on my wheel.
 
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A great article on butted spokes for those of you who haven't read "The Bicycle Wheel" by Jobst Brandt:




Speaking of stiff rims this one I am linking below would have been perfect for your cargo ebike:


It's got 29mm internal width, rim brake compatible, shader valve and the ability to order custom spoke hole angles for use with large diameter flange ebike hub motors.


Too bad it is not available in 26" size.
Cool. Also too bad you can't find the Andras anywhere, and the sales person was a jerk to me. Very snobby.
 
Piggybacking off this thread, if someone has the Voilamart hub motor and was going to get the SE Bikes J35S Rim as mentioned a few times in this thread and others, does anyone know what the right size spoke for that would be? Having a tough time trying to find a calculator that has both these things and I have to say I know the E part way more than the Bike part.
 
If you have the measurements for the ebike part (motor) then put those into the calculator (like the one at ebikes.ca), and get the rim measurements from the rim seller or manufacturer's pages. In this case I don't see the needed info on the linked page above, and the SE Bikes site doesn't even list rims at all, so you would have to contact them for this info.

If you don't have the motor info either, and don't yet have one to measure yourself, you could try contacting VM for that, but I doubt they have the info or would/could get it for you; there might be a thread here with it already but I didn't see it.

The resulting length will also depend on how you intend to lace it (crossings, spokeheads all in or all out or alternating, etc)

When you do get the right measurements and determine the length you need, I recommend using Sapim 14/15 butted spokes, or 13/14butted if you really know for sure you have to use thicker ones for some reason, but not any bigger than that.
 
Piggybacking off this thread, if someone has the Voilamart hub motor and was going to get the SE Bikes J35S Rim as mentioned a few times in this thread and others, does anyone know what the right size spoke for that would be? Having a tough time trying to find a calculator that has both these things and I have to say I know the E part way more than the Bike part.
The published ERD (effective rim diameter) of the 26 inch version of J35S is 538mm.

If you can find the data for your hub, put it into the Grin spoke calculator. Cross-1 lacing, all elbows outside the flange unless your hub has a lot of offset.
 
I JUST did this same process on my ebikeling dd hubmotor. Used the components recommended by chalo and AW (you will see them listed in my recent posting:

Well worth the effort!

Hubmotor vendor Ebikeling gave brain-dead answers to my inquiries for hub flange dimensions so I took my own hub measurements (while it was still laced up) following the processes described in this entertaining Grin Tech video:

How to Measure Hubs and Rims for Perfect Spoke Lengths, Ebike Hub Motor Wheelbuilding

(Those three videos on that page are extremely well done, and pertain specifically to ebike hubmotor wheelbuilding.)

If I were to do it again I would get the spoke head washers for sure, do not skimp on these. My suspicion is that all the commodity hubmotors (voilamart, ebikeling, etc.) will need them when using the preferred Sapim Strong 13/14ga single butted spokes.

 
If I were to do it again I would get the spoke head washers for sure, do not skimp on these. My suspicion is that all the commodity hubmotors (voilamart, ebikeling, etc.) will need them when using the preferred Sapim Strong 13/14ga single butted spokes.
If one is up for it, a second set of holes in the flange for smaller spokes can be drilled instead; this is what I did for my MXUS 450x motors, as they had HUGE holes for motorcycle-sized spokes (even 12g would've rattled around in those holes, possibly being able to be pulled thru, and the 13/14 I used could just pass the head right thru the hole on at least one of the motors (they're two different versions and windings)).

In theory this can weaken the flange...in practice on my very heavy heavy-cargo trike (SB Cruiser), it still hasn't caused any problems for the one of those motors that's still on the left side (the other had axle and winding problems).
 
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