X57 shock dimensions - cone and eyelet

[whisperdancer]

Hi all.

Does anyone know the dimensions of the cone (large and small diameter, lenght) of a NR shock that fits a x57 strut and the width of the eyelet that enters the frame?
My shock is up for a rebuild and I'm modeling adapters to fit a SR Suntour Epicon LDO (which clears the frame nicely in the attachment plate area).

Thank you.

[Colin]

Mine hasn't changed size.................<GRIN>
http://idriders.com/proflex/smf/index.php?topic=3636.msg27405#msg27405

Col.

[whisperdancer]

Thank you very much.

What do you mean by "depth = 10mm plus 5mm above reducing down to 15mm again"?
Looking at a NR2 shock, there is only the cone, nothing else...

[Colin]

"On the x56 bikes the "cone" was a separate piece (correct name is split collet) to fit onto an ODS shock as in the picture"
Looking at Piece #6, from the end that the bolt fits into, it is 10mm long (deep) as it expands in diameter and then it is 5mm long (deep) as it reduces in diameter to 15mm.
http://idriders.com/proflex/resources/97_spc657_strut.pdf
Maybe  I need to draw it..............?

Col.

[whisperdancer]

"On the x56 bikes the "cone" was a separate piece (correct name is split collet) to fit onto an ODS shock as in the picture"
Looking at Piece #6, from the end that the bolt fits into, it is 10mm long (deep) as it expands in diameter and then it is 5mm long (deep) as it reduces in diameter to 15mm.
http://idriders.com/proflex/resources/97_spc657_strut.pdf
Maybe  I need to draw it..............?

Col.

I don't know if the dimensions are the same as the ODS 657 shock or not, but I'm trying to replicate the cone of a 957 NR4.
So far, I only have doubts about the cone dimensions on this aluminum adapter:





I know it looks beefy, but I don't want to take risks.
A small recess is missing in the cone area, similar to the noleen shocks (which should give more friction in the assembly), and the hole for bolting the adapter to the strut is tapped all the way.

EDIT: took the mensures from a NR1 shock and they are the same: 15mm to 20mm diameter, 10mm deep. The bushing width with shock is 30.8mm (I guess 30mm is OK.

[whisperdancer]

Done.
Now down to the machinist...

[Spokes]

Well if the finished item turns out anything like your drawing it will be brilliant. Well done.

Chris

[Colin]

What material will you be using? Stainless?
Might be worth checking what the cost difference is between making one and say 6 or 12...............?
Portuguese labour costs might be a lot cheaper than elsewhere in Europe?
I reckon there's be a ready market for a few of these?

Col.

[Spokes]

I'll have to measure a Fox shock, I wonder if it would fit a Fox float ?

Chris

[whisperdancer]

What material will you be using? Stainless?
Might be worth checking what the cost difference is between making one and say 6 or 12...............?
Portuguese labour costs might be a lot cheaper than elsewhere in Europe?
I reckon there's be a ready market for a few of these?

Col.

This is meant to be made out of a 6 or 7 series aluminum. That's why it's rather beefy.
I made a quick FEA analysis and it seems good.
I'm going to have this made at the guy who was trying to rebuild my NR4 shock.
He rebuilt it once but it leaked in the first ride. He tried to rebuild it again, made a new seal (since the rebuild kit shipping costs are outrageous from USA) but found a deep scratch on the shaft inside the shock that he had no idea how it got there.
So, I paid for a service yet to be done and it's seems there is no solution for the NR4.
As he has his own modified shock on the market, he has easy access to a machinist who can do this.
As an alternative I have some suppliers who have some lathes and could this for me, or as a last resort I could speak to a friend that works for the same group making aircraft parts and CNC the adapter.
I think this will be a one off...

But I can share the 3D model.

As for the fox shock, it's just a case of measuring the eye. The adapter can be easily modified. There is an internal shaft on the eye for the screw to pass through, as I am locking the adapter into the eyelet wall to have more surface contact.

[whisperdancer]

Another thing: this Epicon shock has an interesting feature, as it allow to rotate a ring that contains the air valve. This way the valve position can be changed in order to clear the frame plates. I can put the lockout lever within reach and the air valve pointing downwards, with no need to grind the frame for shock clearance.
Unfortunately, I had to go to a 165mm shock lenght in order to keep the geometry of the frame (considering the NR4 shock has 190mm eye to the strut, which means I will loose 12mm total wheel travel (no problem as this will be ridden mostly on tarmac).

Here is the drawing (made in a hurry) for the adapter:

[kiwi]

surely you can make the shock the same length via adaptor length( 190mm) to retain geometry,the stroke of the shock is the 1st limiting factor.or am i missing(or misinterpreting something?)

[whisperdancer]

surely you can make the shock the same length via adaptor length( 190mm) to retain geometry,the stroke of the shock is the 1st limiting factor.or am i missing(or misinterpreting something?)

If I use a 190mm shock, half of the eyelet would be inside the strut, with no room for the adapter.
The drawback of a 165mm shock is the shorter stroke: there are no 165mm shocks with 50mm stroke, only around 38-40mm, so, while retaining the original geometry, sag will be reduced as well as the total amount of wheel travel.
Best solution would be cutting the cone of the strut and weld some plates to attach a 200mm shock. I think Simon did this to a 957. Maybe someday I will get my hands on a spare strut to try this.

[whisperdancer]

http://youtu.be/ZCDlnwfRvso

[Spokes]

Thats really cool. Is that your adapter being made and by who? Will these be available for others to order?

Chris