Stongest tandem ebike wheel build help

You'd be much better off with 14ga and even better with 14/15ga butted.

What you've got is going to self loosen, crack your rim, or both.

The strength of the wheel is in the rim, not the spokes.
 
Sapim
Strong 2.3 - 2.0
Laser 2.18 - 1.8 - 2.0
Race 14G 2.0 - 1.8 - 2.0
D-Light 2.0 - 1.65 - 2.0
Laser 2.0 - 1.5 - 2.0
Super Spokes 1.8 - 1.4 - 1.8



http://www.sapim.be/spokes/butted/strong
 
Thank you for the spoke recomendations & i even got a couple ideas for the best rims to use. Found out the front 21" mc wheel is 14 ga stainless. When i go to 21 mc wheel in the rear later i will use 12ga, perhaps the e-strong brand. The custom rear hub under works will be strong enough & the aluminum mc rim with fitment washers should take the tension just fine, be better for the load & have some give than going thicker. But i like 14ga also but just want to try 12ga spokes for rear. Thanks.
Ill keep nice in tight every once in awhile, & its rolling smooth! I can now run my curb address painting & sign business the way i like. Im going to take a photo shot with my custom 8ft trailer.
 
danscomp has spokes online, but they got more in stock if you call them. Plus I just learned that they ship internationally, so thats good for Canadians.

Chalo recommended them if I am not mistaken.

Also of note:
Niagara has spokes from 182mm on up, and yes you have to go through each page.

Chain Reaction Cycle has spokes from 184mm I believe, and its the easiest to filter sizes.

Havent checked out JensonUSA yet.

I found a fella on ebay selling Sapims custom cut for reasonable price.
 
orange streak said:
Hear is a close up. Also 8 speed freewheel im forcing in costs money also.
2018-04-18_15.30.02.jpg
Click to expand...

I never would use 12GA spokes on this hub. They probably have drilled out the holes to make the large spokes fit.
With a flange diameter that small there is not much material between the spoke holes which means there will be high risk of tearing the hub apart.
If weight doesn't matter, i would always pick the hub with the largest spoke hole diamter - especially at the rear where torque needs to be transferred or if disc brakes are used.
 
madin88 said:
orange streak said:
Hear is a close up. Also 8 speed freewheel im forcing in costs money also.
2018-04-18_15.30.02.jpg
Click to expand...

I never would use 12GA spokes on this hub. They probably have drilled out the holes to make the large spokes fit.
Click to expand...
No modification to hub to make spokes fit. I dont completly support the spoke size with this hub. But the new custom stong hub will have a high flange drilled for proper use with motorcycle rim so i can add more tension.
 
I just upped my spokes to 12G from 13-14 double butted. I wont go much bigger in size then that.
I got some unknown rim that was used on a IGH. So I had a pair, both 36. One got destroyed. You ever been riding along and bam all of a sudden you are 6" lower because the rim collapsed. Well I tell you that day wasn't fun. One of those, just get home, frock the rim.
 
https://www.worksmancycles.com/#
I was pedicabbing in Hawaii from '84-'88
Those chrome steel rims are the heaviest strongest I've seen
The ones we used didn't have a flat face for a brake they looked like scooter/motorcycle rims
 
Robert Larrison said:
https://www.worksmancycles.com/#
I was pedicabbing in Hawaii from '84-'88
Those chrome steel rims are the heaviest strongest I've seen
The ones we used didn't have a flat face for a brake they looked like scooter/motorcycle rims
Click to expand...

I've built up a number of those. They are very heavy, but not nearly the strongest rims. The main functional problem with them (besides not accepting rim brakes) is that they're drilled for 10ga spokes so they can't stay tight. They impose constant maintenance to keep the spokes done up. They're basically 1890s tech. Superior to wagon wheels maybe, but we can do better.

The pedicab manufacturer I work for has a new run of custom 48 hole, 64mm wide double walled and eyeleted rims in production. Those should be the undisputed king of the mountain among high strength bicycle rims. Since pedicabs are standardized on 48 hole hubs, there are no plans for us to make 36 hole rims that would work easily with hub motors. But for mid drives, there will be a new and formidable option.
 
Chalo said:
The pedicab manufacturer I work for has a new run of custom 48 hole, 64mm wide double walled and eyeleted rims in production. Those should be the undisputed king of the mountain among high strength bicycle rims. Since pedicabs are standardized on 48 hole hubs, there are no plans for us to make 36 hole rims that would work easily with hub motors. But for mid drives, there will be a new and formidable option.
Click to expand...

I understand that this may be a pretty dumb question, but is is possible to use a pattern here every fourth rim hole is skipped in order to lace a 36 hole hub to a 48 hole rim ... and still have a solid, stable and strong assembly? With symmetrical skipping of one hole, it seems like it might work well.
 
markz said:
I just upped my spokes to 12G from 13-14 double butted. I wont go much bigger in size then that.
Click to expand...
It's usually good to do that--to go from a too-large size that goes slack too easy (or breaks the rim trying to tension them enough) down to a smaller thinner size that can stretch and be tensioned correctly without damaging the rim.
 
wturber said:
but is is possible to use a pattern here every fourth rim hole is skipped in order to lace a 36 hole hub to a 48 hole rim ... and still have a solid, stable and strong assembly? With symmetrical skipping of one hole, it seems like it might work well.
Click to expand...
It'd work, and for most uses it'd be perfectly ok. I suspect it'd be less than perfect on an application like the pedicabs, or my piano-hauling trailer (but even on that, it'd probably work fine). ;)

There's some good info on the Sheldon Brown site about lacing unequal hubs and rims.


I've got a Specialized bike here (abandoned by it's original owner after he broke the BB bearings and he never came back to have me fix it, probably because it also has a cracked seatstay) that came with (IIRC) 37-hole rims laced to 36-hole hubs (whatever teh numbers, it has one more hole in the rim than the hub, so there's an unsupported gap in the rim end of the lacing on each wheel). I don't think he ever had problems with the wheels, though he was a big guy; dunno how hard he rode the bike.
 
wturber said:
I understand that this may be a pretty dumb question, but is is possible to use a pattern here every fourth rim hole is skipped in order to lace a 36 hole hub to a 48 hole rim ... and still have a solid, stable and strong assembly? With symmetrical skipping of one hole, it seems like it might work well.
Click to expand...

I reckon it could be done with as few as two different lengths of spoke per side. I laced my 32 hole Rohloff hub (drilled with extra holes for a total of 56) to a 48 hole rim when I first built it up. That took two different spoke lengths in a crow's foot pattern.

The unsupported spans would make the wheel weaker than a normal 48 spoke wheel, but probably comparable to a normal 36 spoke wheel.
 
wturber said:
is is possible to use a pattern here every fourth rim hole is skipped in order to lace a 36 hole hub to a 48 hole rim ... and still have a solid, stable and strong assembly? With symmetrical skipping of one hole, it seems like it might work well.
Click to expand...
I used to do that with my Brompton because it came with a 28 hole Sturmey and I didn't want to special order the 28 hole rims. I replaced about a rim a year from brake wear - on an industrial road with lots of construction grit. It was easy to lace and true, it just looked really weird. The straightest run spokes poked thru the nipples a bit, and the longest runs were a bit short, but I just put enough tape inside. I don't remember having to tighten up often, nor breaking any spokes. But I'm light and the Brommie has rear suspension. Also since the Sturmey doesn't have a gear cluster, there is no dish.

I don't remember the Jobst saying anything about skip-a-hole lacing, maybe the deviant practice was too beneath him to mention.
 
amberwolf said:
markz said:
I just upped my spokes to 12G from 13-14 double butted. I wont go much bigger in size then that.
Click to expand...
It's usually good to do that--to go from a too-large size that goes slack too easy (or breaks the rim trying to tension them enough) down to a smaller thinner size that can stretch and be tensioned correctly without damaging the rim.
Click to expand...

I know that 12G is the max I should go because bicycle wheels need elasticity. I am just going to see how it works out for now with 12G on current rim (yes I had to drill out the holes) I normally always go for double butted 13-14G. But I had some 12G laying around that were the right length +/- 1mm on 543mm ERD rim and MXUS 3KW motor v2.
 
Chalo said:
The unsupported spans would make the wheel weaker than a normal 48 spoke wheel, but probably comparable to a normal 36 spoke wheel.
Click to expand...

OK. Then no real advantage then. Was just thinking that other aspects of the wheel design might make it worth the trouble.
 
wturber said:
Chalo said:
The unsupported spans would make the wheel weaker than a normal 48 spoke wheel, but probably comparable to a normal 36 spoke wheel.
Click to expand...

OK. Then no real advantage then. Was just thinking that other aspects of the wheel design might make it worth the trouble.
Click to expand...

I'm talking in terms of principle. The rim being roughly twice as strong as the next best thing would mean the wheel could be twice as strong as a 36 spoke wheel with a more familiar rim. But for 36 spoke wheels, you have some other options, like the Origin8 DAT-PRO 65 I've recommended many times before.
 
http://www.sapim.be/nl/where-and-when-does-a-spoke-break-nl

I've just been reading up on this, Spoke Breakage.



Where and when does a spoke break? (nl)

Normally just before the bend (this is fairly standard after many years use)

The rim has been damaged - even the smallest dent can be the cause;
The use of non-compatible components;
Irregular tension on the spokes;
A gap exists in the spoke-nipple alignment;
Is it possible to replace 1 or 2 spokes or do you have to replace all the spokes and re-spoke the wheel? If you do not re-spoke the wheel, the replaced spokes will have to be very tightly tensioned if the wheel is to be round and true.
Do not forget when the first spoke breaks, all the other spokes suddenly have a different tension pattern! Also the rim structure goes out of line.
If you only replace 1 or 2 spokes, you can expect these or the spokes next to them to break again. It is best to re-spoke the entire wheel and to replace the hub just in case the hub holes are damaged. It is possible to re-use the hub by mounting the spokes in the opposite direction (i.e. not in the direction of the ovalisation of the hub holes).

The spoke head breaks off (this is unusual)

Bad positioning of the head in the hub (e.g. a slant position puts all the pressure on one side of the bottom of the spoke head. As a result the head snaps off, the so-called "bottle cap effect").
The hub flange is too thick and is not suited to the length of the spoke bend (i.e. all the pressure is on the head, which will be excessively stressed and rip off).
If the wrong cross pattern is chosen, e.g. cross 4 on large flange hubs, the spoke bend can rub against the adjacent spoke head. This should be avoided.

The spoke thread breaks in the nipple

This often occurs as a result of nipple/rim and spoke mis-alignment.
If spokes are used which are too long, new threads in the nipple will be made. Under heavy pressure the spoke threads will be stressed too greatly.
Spokes which are too short may also break at the spoke thread.

When the thinner middle section breaks (on single or double butted spokes)

Any object striking a moving wheel causes damage (sometimes only visible with a magnifying glass or microscope).
Top quality manufacture will safeguard against damage. Lower standard processes will produce an inferior quality. SAPIM draws wire in such way that no change in molecular material structure occurs. The spoke does not twist much when it is built into a wheel.
Aerodynamic, elliptical spokes, such as the SAPIM CX-Ray spoke, are best fitted with a special CX-Ray key.
This will prevent the spokes from twisting during lacing and centring.
Click to expand...
 
Those cats really, really need to read Jobst Brandt's book. They have some nuts (and bugs) in their cookies.

It's generally bad practice to relace a hub in a different pattern than it was originally laced in. There are reasons to do it, but in the absence of a good reason, lace it the same. Much of the break-in type activity has been done already. Hub flanges do tear out sometimes-- especially when laced in patterns that pull more outwards than tangential to the hub flange-- and lacing spokes at oblique angles to their original notches invites this kind of failure.

Also, once spokes have demonstrated reliability, they'll probably continue to do so. If a wheel didn't get stress-relieved and breaks a half dozen spokes in quick succession, you can bet the rest of them will follow in due course, and you should relace it with good new spokes (and remember to stress-relieve them). But if it's gone many thousands of miles and only suffered one or two spoke breakages, there's no reason to swap out the ones that are doing their jobs. Replace the broken ones, stress-relieve them, and carry on.
 
I think if you want really strong wheels (that won't cost a fortune in expensive bicycle rims), you really need to go to moped rims and convert to a disc brake. This is what the hotrod ebike guys are doing with their high power hub motor builds, and having a high weight load is a similar issue, you are just loading the the rim through increased mass rather than increased speed/momentum.

Some info and links to suppliers here

https://www.electricbike.com/moped-rims-tires-hubmotors/
 
Grin Tech does not sell 12G, all they have for sale is 13 and butted 13-14G.
Thats gotta tell the consumer something - That 12G is not necessary for strong wheels.
I ask myself why dont they sell anything thinner.
 
I was watching a 1.5hr motor lacing and a suggested video popped up.
I am always checking my spokes because of my weight.

https://youtu.be/aFLIGRj2bxU?t=67
 
1.5 hours to lace a motor wheel is very long. I lace only 5 or 6 wheels a year, yet doing them in 1 hour. Using a robust bicycle rim, ideal spoke size is 14ga. Ideal lacing pattern is alternate single cross. Single cross with all spokes out, or inside the flange, is acceptable with some motor/rim/frame combinations. Some rims do require side cross pattern to make a stiff wheel, because their alternate spoke spacing width is too close to flange width. The best lacing job is done using the best quality SS spokes, long brass nipples, flange and nipple brass washers. Flange washers can be Alu, nipple washers can be steel, both acceptable. Spokes and nipples need to be tight in perfect alignment. The best wheel is the one that is perfectly true and tight, everything else is secondary, so one can say the best wheel is the one that is maintained without compromises.

Motorcycle wheels do require less frequent maintenance, but they need to be true and tight just as well to be reliable. Altogether, motorcycle wheels, spokes, rims and tires, are lower maintenance and longer life, but this is at the cost of extra weight, thus performance and efficiency loss.
 
Where was all this advise when I was asking for help with building a heavy duty wheel? (grumble grumble)

Anyhow, after thinking on it and researching over the last year, I went with a pair of Alex DX32 36h rims. From what I could find, these rims were pretty well regarded, and I only found just a few mentions of bent or broken rims. The general consensus of the DX32s is they are nearly indestructible.

Orange Streak, after mulling over what to do for my own wheel build, I came to the conclusion that 14ga butted spokes were the best choice for the use case I am planning for. The only difference that your rig and mine is that you have more weight on the rear with your batt packs, and I also have a rear suspension. But we do share the issue of a high speed impact with pot holes.

I am going to pretty much echo what the others have said here already, the thinner spokes would be more durable. Strength is not the key here, you want some flex. Hitting a pot hole at a high speed will cause a huge spike in forces to a very small area on the rim. By having thicker stiffer spokes, the rim and spokes will not be able to flex as much to absorb the impact.

I've seen a guy bend the rims on his BMW 3 times within a few months, hitting pot holes in this city. The rims were 22-24in, with thinner tires than those cars normally come with. Theory is the same, even though his issue was mainly due to the thin tires. It's the sharp impact force that causes the damage, and thin tires and thick spokes make for much less deflection when impacted.

Wider rims I think are a step in the right direction. Increasing the total volume of air in the tire should make a difference. As wide as you can get away with on your frame.
Have you considered a rim with cut holes between the spokes, like fatbike wheels have? The openings allowing for tube or rim strip to expand out the holes a bit on impact, may lessen the forces against the rim/spokes. I personally would be concerned with the strength of those rims with that much weight on them, but I also do not have any experience with fatbike wheels. Maybe an option to consider looking at.
 
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