heavy rider spokeless integrated hub motor. Discuss?

[spinningmagnets]

I re-viewed the OP first post, and he seems to be talking about a street commuter. If the roads are smooth, its almost not an issue at all, especially at lower speeds (the wheel shown as an example, is low-powered and low-speed). However...

I would never use a cast wheel in an off-roader, which is intended to take bumps and jumps frequently. The ones that are strong enough to take hard hits (from E-motorcycles) are very heavy.

For a heavy rider, smaller diameter wheels are stronger than larger diameter (that being said, their are flimsy 20-inch rims, and heavy-duty 20-inch rims).

Full suspension will soften a pothole hit, compared to a hardtail, or a no-suspension.

Fatter tires will soften a pothole hit more than skinny tires (2.5-inch/3.0-inch is better than 2.0-inch, it doesn't have to be 4.0).

Moving the weight of the motor out of the hub and mounting it onto the frame somehow will make the rear wheel more survivable from a hard hit.

 

[rborger73]

Most people using ebikes aren't trail riding in my opinion. Mid drive is fine for some, but then you are involving chain issues, noise, and other issues. Without a hub motor involved, it's a very different discussion. I personally love a hub motor, and would never go mid drive. Point of the thread is, ebike rims will evolve, and it won't be evolving to more spoke rims. Consumers will start destroying their rims the more popular ebikes get. Ebike deaths are not the way we need the future to go. Look how many new ebike companies came out in just the last year. As the market grows, rims will have to get better, and with new things being
discovered, they will change.

 

[Chalo]

They picked all kinds of gimmicky bullshit for the futuristic e-bike, to help it play to the cheap seats.

A wire wheel is the original tensegrity structure. It works by trading structural loads all across its structure, rather than only at the point of load. Until one-piece wheels can have their spokes tightened to accomplish the same thing, they'll never catch up to wire wheels. Wire wheels will be able to adopt the same supermaterials that make reasonably light and strong future mag wheels possible, and then display the same advantages wire wheels have always had.

The same thing that makes them adjustable and repairable is what makes them structurally superior to unstressed unit wheels. If you can't understand why this is so, you need to do some research or else stop making pronouncements about things you don't understand.

The Bicycle Wheel by Jobst Brandt is a good place to start.
https://www.amazon.com/gp/aw/d/0960723668

 

[rborger73]

The Ebike Wheel by Someone Else.

 

[rborger73]

For the last time.. .Consumers are not going to want, nor have the ability, and time to adjust their ebike wheels. When you go from the consumer being a hobbyist, to the mainstream consumer market, spoke wheels will start to go away, just like they have in every other industry involving a wheel...

 

[markz]

come on, its just a simple bicycle with spoke wheels since its invention in mid 1800's.
Its not going anywhere.

 

[rborger73]

But.. it isn't the same.... Ebikes are not the same as a normal bike, and when you get north of 2000 watts.. it makes a big difference. Spoke wheels on an ebike go out of true way faster, and spokes come loose way faster. It absolutely not only will change, but MUST change.

 

[MadRhino]

Spoked wheels don't get out of true, and spokes don't get loose until they hit pretty hard.

If they do, it is because they are machine built with cheap Chinese spokes, or never tensioned properly. 2000 watts doesn't change anything to that fact, 20 000 watts doesn't, 40 HP on a 450 lbs motorcycle doesn't either.

Then, a hit hard enough to crook a spoked wheel might as well crack a cast wheel. KTM equipped some of their light weight dual sport motorcycles with cast wheels a few years ago, now they are back to spoked wheels after too many scrapped expansive cast wheels claimed within the one year garantee.

 

[DRMousseau]

Jus now starting construction of a new build with OP's similar concerns of "a heavy rider" on a rear hub-motor. I my case, the rear wheel has to support an adult rider AND passenger of approx. 300-400lbs total, and NEARLY ALL WITHIN the circumference area above the 26" rear wheel assy. So I have to address the possible issue of shortened bearing life here, AND a strong, supportive wheel assembly in a rigid frame.

And mostly,.... what TIRE will I need!!!! This gives the OP a LOT more choices than I may have, among available rear wheel assemblies of cast or spoke designs to suit his needs, but may depend on, "what tire do I need, and will it fit and work with these assemblies?" OR,... "what tires will fit these assemblies, and will they suit my needs of weight and use?". Fortunately "highway ratings" aren't necessary in choosing an e-bike tire, but construction quality based on desired use IS important!!!

A poor tire choice, is gonna reap havoc on ANY wheel assembly, cast or spoke, if it endures a catastrophic failure. Of course, a good tire on a poorly constructed or designed assembly won't last long either.

BTW,.... do they make good cast large-hub assemblies in wider bicycle rim sizes??? Or must we be forced to use a spoke rim???

 

[Chalo]

For the last time.. .Consumers are not going to want, nor have the ability, and time to adjust their ebike wheels. When you go from the consumer being a hobbyist, to the mainstream consumer market, spoke wheels will start to go away, just like they have in every other industry involving a wheel...

You keep saying it like it's going to become true, but bicycles have had 150 plus years to illustrate your concept, and... no. Everybody who buys a bike gets wire wheels, to the nearest approximation. And they make it work, better than they would with cast nylon wheels or cast aluminum wheels or imaginary cast wheels made of graphene and unicorn horn. Tons of motorcycles have wire wheels and don't display any more problems than similar motos with mag wheels.

Other vehicles have adopted one-piece wheels for various reasons that don't apply to us: They're a little cheaper, they work well with very wide tires on relatively small diameter wheels, and designers of those vehicles fundamentally don't care about efficiency or performance at a fixed power. They just add more power (and pollution, and noise, and death count). Despite what you keep saying, this latter bit is not characteristic of e-bikers.

 

[rborger73]

Spoked wheels don't get out of true, and spokes don't get loose until they hit pretty hard.

If they do, it is because they are machine built with cheap Chinese spokes, or never tensioned properly. 2000 watts doesn't change anything to that fact, 20 000 watts doesn't, 40 HP on a 450 lbs motorcycle doesn't either.

Then, a hit hard enough to crook a spoked wheel might as well crack a cast wheel. KTM equipped some of their light weight dual sport motorcycles with cast wheels a few years ago, now they are back to spoked wheels after too many scrapped expansive cast wheels claimed within the one year garantee.

Spokes don't get out of true? Ok. I'm done. You folks keep pressing spoke wheels are cheaper, but then say only "cheap Chinese spokes" go out of true.. So now you have to have expensive spoke wheels to avoid going out of true.. Gotcha..

Again.. spoke wheels on ebikes will start to go away. The cast wheels you keep talking about, will improve, and I guarantee I never would have had to adjust a cast wheel, nor would I have broke one in 18k + miles. Most ebike sales aren't to people using them on trails and rough terrain. If they are they have suspension and tires to accommodate the abuse. You don't buy a street bike to ride on trails, if you do, you are very likely to damage the bike.

 

[markz]

Nipple threadlock is meant to prevent seizure, much more important than locking the thread. When a wheel is laced tight, nipples don't come loose by themselves. If there is a loss of tension after a while, it is because of spoke stretch and placement. Once this is corrected, the wheel will stay stiff until a hard hit. If there is a long time before the wheel hits enough to require the next correction, nipples might be seized if they were not installed with threadlock. I use linseed oil like many old wheel builders do, but any brand of nipple threadlock, blue Locktite or ski wax will do as well.

How long do you have before the Blue Loctite "hardens"

Also I was stupid and never did nothing to the threads before I laced and tightened nipples. I was hoping I could drop some Blue Loctite from above (outside) the rim. I am in the finishing stages of evening up the nipples. The spoke end is about 1/2 to 3/4 up to the bottom of the notch.

I am taking it slow this time, last few tries were gong shows, all due to my wanting to ride NOW!!!! But I dont want to frock up these China spokes.

Good brand name nipples with old CCM used spoke.

 

[MadRhino]

Blue Loctite never hardens, it does coagulate quickly to a hardness similar to cold black chocolate and stays like that for years. All thread prep have one common property: they never dry hard. They are anti-seize.

Blue Loctite is formulated especially for parts that need to be disassembled, and to make disassembly possible even after a very long time exposed to extreme conditions.

Red Loctite is made for permanent assembly. When applied in proper conditions, it does seize in a few hours to a hardness similar to long time corrosion.

 

[Chalo]

Purple Loctite is weaker than blue, and specifically designed for small diameter fasteners like spokes.

Anything that interferes with turning spoke nipples when it's time to true a wheel is a nuisance. Threadlock should only be used to treat a problem that spoke tension alone won't fix. And because there's nothing actively twisting the nipples to loosen them, the weakest sort of threadlock is more than adequate. Linseed oil is traditional for the job.

The best approach is to use wheels that don't suffer loosening spokes. It's pretty easy to do if you observe a few basic principles.

First, use appropriately thin spokes. For bicycle wheels-- even big strong heavy-duty bicycle wheels-- that means no thicker than 14ga (2.0mm). 14-15ga butted spokes are better. Don't be tempted by the false premise that thicker spokes make a stronger wheel or suffer fewer breakages. A wheel with thick spokes is a less reliable wheel. If you have a highly dished wheel where the spokes on one side must be much looser than the other, use even thinner spokes, like 14-17ga, for the loose side. They'll resist loosening at low tension much better than thicker spokes.

Second, use an appropriate rim. The rim is where you need to focus if you want an especially strong wheel. The stiffer it is in the plane of the wheel, the less movement there is for the spokes to have to follow. So if you want to beef up the wheel, use a stiffer, heavier, deeper rim-- but use the same thin spokes you'd use on a lighter rim. Do not waste your time with single walled rims; those represent lost opportunities to have stronger wheels.

Third, get the spokes tight enough, with tension as uniform as you can make it. On the tighter side of the wheel, the loosest spokes should have at least 100 kgf of tension and the tightest ones should not exceed 140 kgf (even if the rim is really badass). Bike shops have tensiometers for measuring spoke tension, and you should not trust feel alone until you've built a bunch of wheels yourself. Lubricate the spoke threads and the nipple heads so that you can get high tension without rounding off the nipples.

If you do all these things, you won't have to glue the spoke nipples in place. The spokes will stay tight without intervention.

 

[markz]

So if you are saying - The purpose of the Linseed Oil/Spoke Prep/Loctite is for ease of tightening the nipple, not to hold the nipple or keep the nipple from spinning. So that there is not extra tension "built up" with a dry nipple.

I haven't used anything on my nipples. I am about 2 to 3mm from the bottom of the slot on the nipple. I am trying hard to keep them all the same, but I think at this point I need to true it, though it looks true enough for me. I find it tough to tighten the nipples, so I am taking it slow. I am squeezing the pairs of spoke, plus I am putting the rim on the ground and flexing the rim itself. This seems to give some spoke/nipples a bit of release.

I am debating whether to go to Home Depot's Paint section and buy a 1L bottle of Boiled Linseed Oil. Then for each spoke I would loosed say 4 or 5 turns, drop some oil into the top of the nipple, then tighten the same amount of turns. Is that just extra work thats not need because I am so close to topping out the spoke to the bottom of the nipple slot?

 

[MadRhino]

I use linseed oil, but it is useless if you put it after the spoke is in the nipple. Proper use is to dip the spoke thread or wipe the thread with a dipped cloth, before inserting into the nipple. You would have to unscrew the nipples or at least, the most part of it.

 

[Chalo]

So if you are saying - The purpose of the Linseed Oil/Spoke Prep/Loctite is for ease of tightening the nipple, not to hold the nipple or keep the nipple from spinning.

No, I'm saying that nipples back off when the spokes go slack and they can wobble around freely. There's nothing actually twisting them, so the threadlock can be weak. But if they never go slack, then there's no need for threadlock.