Welding e-bike frame from scratch. Questions about the swing arm.

[My First Ebike]

Hi, Guys Like the title says I'm building my whole e-bike from scratch. I have the design already but I'm wondering what type of bearings to use for the rear suspension swing arm, so I can size and design the holder accordingly. I want some good bearings that are not overpriced or hard to get. I thought i would ask here, i assume this has been tackled before.
There is still time to tweak the design so i don't mind suggestions on different types. I think the inside diameter of the tube to press the bearing into is usually 28mm at least for the ones i have found on Aliexpress?
it will be a robust e-bike/motorbike made from rectangle and square tubes.

 

[Papa]

You'll need a lot more than just bearing OD. But i'll throw-out a quick link to appease your request...

12mm x 28mm Enduro MAX Sealed Bearing: SBMAX-6001 - Bicycle Parts Direct

Enduro 6001 MAX sealed bearing. Designed for suspension pivots. MAX bearings take 35-40% more load capacity than standard radial bearings.

bicyclepartsdirect.com

 

[Chalo]

Signs point to you not being ready for a scratch build. Maybe try an e-bike conversion first? A non-suspended bike first? Focus on building knowledge and skills.

 

[My First Ebike]

I like to learn the hard way, it's the fastest.
I've seen people install and remove bearings on motorbike swing arms and all i see is a Tube precisely machined to press fit a bearing on both sides. What could be so hard?
Thanks for the link aswell

 

[My First Ebike]

I think i will manage guys i just need a few pointers from the people who have already made the mistakes. For example which suspension parts to avoid etc. If somebody wants to teach I'm definitely here to learn so your time won't be wasted. Thanks

 

[Chalo]

Do you weld already? What kind of welding? Do you have access to machine tools (lathe, mill) and already know how to use them? Let's figure out where you're at.

 

[My First Ebike]

I can stick weld. I don't have a mill or lathe. But if those processes become vital I can have it done. I do hope to use as many off-the-shelf parts as possible. It's built with rectangular and round steel tubes and some sheet material so far, nothing that can't be shaped with the tools I have.

 

[My First Ebike]

Do you weld already? What kind of welding? Do you have access to machine tools (lathe, mill) and already know how to use them? Let's figure out where you're at.

i kinda designed the frame based on the tools i have. As i was designing it i was thinking about the build process.

 

[Papa]

I would suggest you start here....

 

[My First Ebike]

I would suggest you start here....

Thanks. ive watched that video already. i get the dimensions and built a rig already.

 

[Chalo]

Thanks. ive watched that video already. i get the dimensions and built a rig already.

But you think you're going to stick weld a bike frame? I mean, sure, but it will need to be as thick tubed as a handrail. And it will look like a degenerative skin condition when you're done with it.

Study more. Be patient; this isn't a trailer hitch you're talking about.

 

[My First Ebike]

But you think you're going to stick weld a bike frame? I mean, sure, but it will need to be as thick tubed as a handrail. And it will look like a degenerative skin condition when you're done with it.

Study more. Be patient; this isn't a trailer hitch you're talking about.

i guess i will have to name it the Degenerative Handrail when I'm done then I guess. I don't know what else to say to that.

 

[My First Ebike]

Are you saying i should learn the other welding technique and then use a thinner frame? i want to use a rectangle tube anyway.

 

[My First Ebike]

 

[My First Ebike]

 

[Papa]

it will be a robust e-bike/motorbike made from rectangle and square tubes.

Stick welding & square wall. Gotcha...

https://www.youtube.com/@ATOMICZOMBIEDOTCOM/videos

 

[My First Ebike]

Stick welding & square wall. Gotcha...

https://www.youtube.com/@ATOMICZOMBIEDOTCOM/videos

Was that supposed to link to a specific video because it was just a channel's main page?

 

[My First Ebike]

Why can't these be stick welded?

 

[e-beach]

Are you saying i should learn the other welding technique and then use a thinner frame? i want to use a rectangle tube anyway.

Do it your way. If you have to scrap the first frame and start over then you will have experienced a first build that will only help you. Everything that I have made from scratch always took more then one build to get it where I wanted it. That includes e-bike builds. There is no way to study experience, you just have to do it to know.

 

[nicobie]

What size tubing are you planning to use? In the pics it looks looks it might be 4X1 OD? If the wall thickness is .25" stick welding by a beginner could be OK. Even a HF wire feed using 3/16" tubing would do a better job for a beginner. Either way I would not want to ride it over too many big bumps.

 

[My First Ebike]

Do it your way. If you have to scrap the first frame and start over then you will have experienced a first build that will only help you. Everything that I have made from scratch always took more then one build to get it where I wanted it. That includes e-bike builds. There is no way to study experience, you just have to do it to know.

Thanks for the breath of fresh air!
Funny how people act, I would think people would just aim to uplift if they have joined a group like this.

 

[Papa]

Was that supposed to link to a specific video because it was just a channel's main page?

It's a link to one of the most experienced stick welding, squarewall frame builders I know. He's been doing for decades. Sort though his stuff, he's quite generous with tips & clues on 'how to do it successfully'.

 

[My First Ebike]

What size tubing are you planning to use? In the pics it looks looks it might be 4X1 OD? If the wall thickness is .25" stick welding by a beginner could be OK. Even a HF wire feed using 3/16" tubing would do a better job for a beginner. Either way I would not want to ride it over too many big bumps.

The creator of that bike in the pic always promotes how he would break other electric bikes so he built his own company. So i assumed it was overbuilt?! (of course hes advertising) But you seem to know about what a frame would take. Do you know where i could find more info on that sort of thing?

 

[My First Ebike]

What size tubing are you planning to use? In the pics it looks looks it might be 4X1 OD? If the wall thickness is .25" stick welding by a beginner could be OK. Even a HF wire feed using 3/16" tubing would do a better job for a beginner. Either way I would not want to ride it over too many big bumps.

i think its 3" by 1" I'm not sure how thick. I think i will have a friend weld it if it has to be way too thick for me to stick,

 

[Papa]

Have you priced new square-wall lately? And you'll need a head tube and BB shell,... and a fork, handlebar, crankset, brakes, and a bucket full of nut&bolts. So why not start with, essentially free, discarded bicycles?

And here is just 'one' of AtomicZombie's overwhelmingly informative vides...