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pegasus
01-25-2017, 04:10 PM
Iím planing my next build, a tadpole trike.

I like to have rear suspension, but I donít have a scrap suspension bike.

But I have this

https://s5.postimg.org/6vy9nlh9z/CIMG1224.jpg

and this

https://s5.postimg.org/ed7h2t6t3/CIMG1225.jpg

If you google bicycle pivot bearings , you get bearings for axles between 8 Ė 15mm.

What to choose?

Instead of bearings,could I use 2 of this
https://s5.postimg.org/8df4lewmv/pos.jpg

Say 10mm?

What about Bronze or Poly bushes?

I need some guidance.

bambuko
01-25-2017, 06:06 PM
Just don't buy cheap Chinese **** from ebay :)
The difference between these and decent ones is staggering even if used only for steering links.

Anyway... I'd wait until you get suspension bike from the dump, rather than trying to do your own thing!

IrvJamison
01-26-2017, 12:57 AM
Take a look at the rear suspension on the Python site. It uses a front fork and rubber piece, would be easy to spread the fork, replace the dropouts. Look at their site: http://www.python-lowracer.de/construction.html and go to #4. Works great and easy to build.

pegasus
01-26-2017, 04:02 AM
Just don't buy cheap Chinese **** from ebay :)
The difference between these and decent ones is staggering even if used only for steering links.

Anyway... I'd wait until you get suspension bike from the dump, rather than trying to do your own thing!

Thanks for your advice.

The picture was for illustration only, I by my bearings from a industrial bearing supplier.

darnthedog
01-26-2017, 07:30 AM
If you really want to do it yourself-You don't need the movement of bearings.
This gentlemen did it with split shaft collars due to lack of suspension bikes for his Timberwolf. He pasted away but his legacy lives on. Check out :http://forum.atomiczombie.com/showthread.php/7119-First-Bike-Build
I am sure Darrell will not mind. And it worked for him.

pegasus
01-27-2017, 09:09 AM
Take a look at the rear suspension on the Python site. It uses a front fork and rubber piece, would be easy to spread the fork, replace the dropouts. Look at their site: http://www.python-lowracer.de/construction.html and go to #4. Works great and easy to build.


Thanks for the input


If I havenítalready bought a rock shock I might have made the rear suspension ina similar fashion

pegasus
01-27-2017, 09:16 AM
If you really want to do it yourself-You don't need the movement of bearings.
This gentlemen did it with split shaft collars due to lack of suspension bikes for his Timberwolf. He pasted away but his legacy lives on. Check out :http://forum.atomiczombie.com/showthread.php/7119-First-Bike-Build
I am sure Darrell will not mind. And it worked for him.

Thanks

Just what I was looking for.

I have some experience with bronze bushes and know how easy they are to grip the axel.

Using a split shaft collar solves the problem.

The only shaft I have is 14mm od and they dont do bearings for a 14mm shaft but the do bronze bushes, so it saves me finding another shaft.

I will weld the shaft to the wheel frame and 2 part shaft collars to the main frame

darnthedog
01-27-2017, 01:31 PM
Thanks

Just what I was looking for.

I have some experience with bronze bushes and know how easy they are to grip the axel.

Using a split shaft collar solves the problem.

The only shaft I have is 14mm od and they dont do bearings for a 14mm shaft but the do bronze bushes, so it saves me finding another shaft.

I will weld the shaft to the wheel frame and 2 part shaft collars to the main frame

You actually only weld the shaft collars to the 2 pieces of frame. The axle is gripped by 1 collar and slips on the internal pair. By welding the shaft the won't be a way to disassemble to replace the bushings if ever. Plus it is harder to pull apart for painting and such.

pegasus
01-27-2017, 02:01 PM
You actually only weld the shaft collars to the 2 pieces of frame. The axle is gripped by 1 collar and slips on the internal pair. By welding the shaft the won't be a way to disassemble to replace the bushings if ever. Plus it is harder to pull apart for painting and such.


I hear what you say

But I thought using 2 part collars like this,

https://s5.postimg.org/run9o0rlj/collar.jpg

so I only need 2 collars

darnthedog
01-27-2017, 05:20 PM
I hear what you say

But I thought using 2 part collars like this,

https://s5.postimg.org/run9o0rlj/collar.jpg

so I only need 2 collars

Due to Twisting of frame due to suspension I would go with whats proven. You need 4 to ensure no twisting at the pivot. Your split collar should work. But 2 on inside and 2 on outside is what Darrell used. Twisting come from pedaling powered from onside to the other. I picked up a home built before becoming part of this group. It had a single side pivot and it twisted so much that it was nearly impossible to pedal even in the lowest gears. I was told it just needed a new shifting mechanism. But it turned out to be a twisting action that had to do with the unbalanced pivot.

You can do what you wish- No one here is saying it can't be done. Just relaying my experience with the two point pivot verse a 4 point pivot.