Buell XB high performance front isolator

[mtz117]

This is truly awesome. Keep the updates coming, I'm really interested.

[TPEHAK]

Here is the zip archive with the updated STEP CAD models and drawings, so you can use it. The CAD models include the changes I implemented while testing.

https://drive.google.com/file/d/0B3I...ew?usp=sharing

[Flatout]

Truly amazing and thorough! Even though you won't be producing these, I feel you deserve a few rounds of beer!

[chief_of_smoke]

I second that

[TPEHAK]

It looks like the isolator does not perform very well. The isolator has no excessive vibrations but after a couple rides the bracket has moved about 5 mm down on the bushing and the top faces of the polyurethane rods had been sheared by bracket edge.







You can see the cut rods







I have a couple thoughts how to fix this issue, but I'm not sure it will totally eliminate excessive wear without radical modifications of the bracket. The sharp edges cut the rods ends, so I'm going to increase the edges fillet radius using file. Another thing I can do is to use stiffer polyurethane rods to support the bushing and put them in another spots, but it will increase vibrations.

[fluffypancakes]

Good work.

I just want to know where you got the XB frame CAD file

[TPEHAK]

I found it in grabcad.com

[fluffypancakes]

Thanks! Keep working on this!

[redheadedshanny]

Hello, curious how you are coming with your testing.
Have you had a chance to try a different combination?
Have you thought about making the sides accept a smaller diameter tube?
Someone had suggested that the original isolater is oval shaped.
Maybe this has something to do with the tubes not holding up?
Maybe a smaller tube on the sides that consist of a harder compound to allow the shock to be absorbed through the tubes on the front and rear?
Just looking to assist.
If you do make a change and want to machine one up let me know.
I maybe able to squeeze one out.

[TPEHAK]

Thank you, but I have no time at the moment to try different options, maybe later. None of the configuration I already tested is acceptable because some of these configurations are too stiff and vibrate too hard, and some of these configurations wear out too fast.

Smaller diameter side tubes will not provide enough vertical support, so I believe different tube hardness is the best option, and it works, just wears out very fast.

There are few revisions of the isolator with different hole shapes and different rubber insert shapes. But for all of them the idea is the same, isolator is less stiffer back and forth direction and more stiffer left-right and up-down directions. The earlier isolator revisions have oval hole shape, the last isolator revision has round hole shape.