Can i use two bearing blocks (for a 20mm shaft) as swing arm mounts?

[MoTiJo2023]

Hello,
I want to build a minibike from a 2 stroke pocketbike i have, becasue the pocketbike frame is cracked and i always wanted to build a minibike, so this is the perfect oppertunity to build one. Imma make the frame for the minibike out of 20x30x3mm mild steel rectangular tubing. Because i want to build the minibike with full suspension i have to make a rear swingarm. On the pocketbike the stock swingarm was beeing held in the frame by a bolt, so it can freely move (the pocketbike sadly has no bushings in there), on mopeds or motocross bikes (higher quality than a china bike) you have the rear swingarm mounted in (i think its rubber) bushings. I dont have any rubber bushings at home, so i want to use two 20mm bearing blocks i have laying around instead of bushings. Can i do that?
My idea would be to make a custom rear swingarm and weld a 20mm shaft onto it that will sit inside the bearing blocks and be bolted onto the main frame (not like on the photo that is shown below, i think you all will get what i mean)

Those are the bearing blocks i mean:

And those are the bushings that you find in mopeds:

This is the part i mean where the bushings normally sit in:

 

[Denny]

I can’t think of a reason why not.

 

[bob58o]

I’ve thought about using pillow block bearings for a swing arm and using a common shaft for swing arm and jackshaft. I’m not sure why it isn’t done more often.

 

[Master Hack]

I’m not sure why it isn’t done more often.

$$$$$$

Actually ball bearings are not the best choice for that. Shock loading can cause brinelling. Due to balls having only a single point of contact with the race. brinelling is where the balls can actually dent the race.



Needle bearings are a mo bedder choice as the spread the contact point out over the length of the needle.

Rubber/poly bushings are even mo bedder cuz the require no maintenance.

 

[Rat]

They use hard rubber bushings a lot like found in a truck leaf spring because they absorb the jolts of force that would otherwise bend the swingarm pivot bolt or tear the bolt through the frame or swing arm... it's unlike the difference between shaping a sheet of tin with a plastic faced mallet versus a ball peen hammer; either works but one is going to do more damage than shaping

 

[Denny]

Ooooh I know the answer to this one! The plastic hammer will do more damage to the sheet metal. Because it is not heavy or hard enough to move the metal. That’s why I only use wooden mallets or steel hammers.

 

[Rat]

Nah it depends on the weight behind the plastic FACE and it depends on the sheet... overall the point was the plastic faced hammer isn't going to ding it up real bad or screw up the surface where a ball peen can make a dent gnarly enough you'll never get it out

 

[Denny]

Ive been working sheet metal since I was 10 years old. Bet I could do more with a ball peen and a tree stump than you can with a plastic hammer.

 

[Master Hack]

I can do more damage to a piece of metal with a mill than either of ya can fix with yer stoopid hammers!

 

[Rat]

Ive been working sheet metal since I was 10 years old. Bet I could do more with a ball peen and a tree stump than you can with a plastic hammer.

Probably could... but I've got a few peens, an anvil made from RR rail, but no plastic. There's a lot I don't do well, but there's very little that I'm not capable of.

 

[Rat]

I can do more damage to a piece of metal with a mill than either of ya can fix with yer stoopid hammers!

I see your mill and raise you by a fit of rage.
Let me know when you make a steel bicycle frame look like it was dropped off the back of a truck and hit by a semi on the highway.
Frame, fork, and handlebars all bent and twisted to hell, both wheels reshaped to pringle...One hand, No tools.

I had my reasons

 

[Functional Artist]

Um...Hello??

What the Sam Hill does any of your guy(s) skills, tools, issues &/or past carnage, have to do with the OP's question?

 

[Master Hack]

What the Sam Hill does any of your guy(s) skills, tools, issues &/or past carnage, have to do with the OP's question?

Oh! was there a question? What was it? He didn't really expect a serious answer, from us did he?

 

[Denny]

What was the question, I forgot.

 

[Master Hack]

I'm purdy sure Functional Artist was selling his new educational program. Something to do with a new power source or something he's working on. Above my comprehension! It was this:

 

[Denny]

I don’t need no education. I’m self learned!

 

[Master Hack]

What the Sam Hill

I know! His house is just a few miles from here.

Samuel Hill - Wikipedia

en.wikipedia.org

 

[BaconBitRacing]

I'm purdy sure Functional Artist was selling his new educational program. Something to do with a new power source or something he's working on. Above my comprehension! It was this:

View attachment 144631

Here's a real life photo of Functional artist:

 

[bob58o]

 

[MoTiJo2023]

$$$$$$

Actually ball bearings are not the best choice for that. Shock loading can cause brinelling. Due to balls having only a single point of contact with the race. brinelling is where the balls can actually dent the race.

View attachment 144589

Needle bearings are a mo bedder choice as the spread the contact point out over the length of the needle.

Rubber/poly bushings are even mo bedder cuz the require no maintenance.

Hmm yeah, you are right. I will just buy a whole kit for the rear swingarm mounts. I have a simson s51 moped, and i can get the kit for the swingarm mounts for cheap from all kind of shops.
Here is a piture of the kit: