Author Topic: The Shiny New AM831 Group Buy (A) Thread!  (Read 128593 times)

Eddy-haideli

Re: The FS830
« Reply #1110 on: December 23, 2021, 01:18:29 AM »
I tried to look a the FS830 and asked for internal schematics. There could be an issue too. If you look at the pivots, there is a bolt on the left side, with the bolt head certainly pinching the inner race of a bearing fitted in the link eyelet. The bolt apparently goes right through and screws into a nut at the link eyelet on the right side, which nut probably pinches the inner race of a second bearing. Not sure how this works, because the link eyelet must be free to turn about the nut. In any case, both bearings are apparently pressed into the link eyelets from the left, meaning that they can't stop the link from moving to the right with respect to the frame.

What are you talking about?
Do you got our mold FS830?

Eddy

Stef Biggel

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1111 on: December 23, 2021, 01:46:55 AM »
Hy eddy,
I think he is trying to see eventually issues in Theorie and nothing be sure. If I will receive my mold I will discuss with JJJ with detail pictures and a demounted link. All other theoretical thoughts are not fair.

Best regards

Eddy-haideli

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1112 on: December 23, 2021, 01:54:12 AM »
Hy eddy,
I think he is trying to see eventually issues in Theorie and nothing be sure. If I will receive my mold I will discuss with JJJ with detail pictures and a demounted link. All other theoretical thoughts are not fair.

Best regards

Thanks.

JJJ

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1113 on: December 23, 2021, 01:57:13 AM »
https://www.alibaba.com/product-detail/2022-T1000-29er-max-29-2_1600122152845.html?fromMSite=true

Hy JJJ,
There you will see more pictures.

That or a similar link is where I got my screenshots. But they don't show the internals of the pivots.

Stef Biggel

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1114 on: December 23, 2021, 02:00:28 AM »
That or a similar link is where I got my screenshots. But they don't show the internals of the pivots.

Right, but the resolution is a bit better. It was only for information.

That’s not showing the internals is clear, for that we have to wait. Otherwise you get some schematics from haideli.

JJJ

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1115 on: December 23, 2021, 02:19:27 AM »
Right, but the resolution is a bit better. It was only for information.

That’s not showing the internals is clear, for that we have to wait. Otherwise you get some schematics from haideli.

A "bit better" still remains bad. There are not many ways ball bearings can be mounted correctly.

I'm having a tough time asking for the schematics...

Stef Biggel

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1116 on: December 23, 2021, 02:30:20 AM »
A "bit better" still remains bad. There are not many ways ball bearings can be mounted correctly.

I'm having a tough time asking for the schematics...

Yes, but it was just the best I could find. No idea whether you even get plans or exploded drawings like with sc. I promise to share the things here as soon as I can provide more information.

Stef Biggel

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1117 on: December 23, 2021, 02:34:48 AM »

JJJ

FS830 links
« Reply #1118 on: December 23, 2021, 02:47:14 AM »
Here is the exploded view, how pivot had it done:

https://www.upgradebikes.co.uk/files/technical/pivot/Firebird-C-Parts-Schematic.pdf

Yes, the correct way, bearing recesses facing outwards, each with a bolt for pinching the inner race of the bearing against the frame body. In the FS830, the left recess faces outward and the right recess inward. Doesn't look good.

JJJ

Re: The FS830
« Reply #1119 on: December 23, 2021, 04:12:28 AM »
I tried to look a the FS830 and asked for internal schematics. There could be an issue too. If you look at the pivots, there is a bolt on the left side, with the bolt head certainly pinching the inner race of a bearing fitted in the link eyelet. The bolt apparently goes right through and screws into a nut at the link eyelet on the right side, which nut probably pinches the inner race of a second bearing. Not sure how this works, because the link eyelet must be free to turn about the nut. In any case, both bearings are apparently pressed into the link eyelets from the left, meaning that they can't stop the link from moving to the right with respect to the frame.

So here is a drawing explaining the potential issue. Bolt in pink screwing into a small grey nut on the right. The link is only held laterally by the press-fit force of the bearings. Once that force fades (and it will in this case), the link can shift to the right until the left eyelet contacts the frame body.
Haideli, please prove me wrong showing us your pivot internals!

JJJ

Re: The FS830
« Reply #1120 on: December 23, 2021, 04:27:36 AM »
So here is a drawing explaining the potential issue. Bolt in pink screwing into a small grey nut on the right. The link is only held laterally by the press-fit force of the bearings. Once that force fades (and it will in this case), the link can shift to the right until the left eyelet contacts the frame body.
Haideli, please prove me wrong showing us your pivot internals!

An alright design would be this. But it's not obvious from the picture of the left side, where the bolt head has a large diameter, usually meaning it covers the whole bearing to the outer race.

So what is the actual design?

Stef Biggel

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1121 on: December 23, 2021, 05:41:35 AM »
JJJ, look to this:
https://chinertown.com/index.php?action=dlattach;topic=3018.0;attach=7199

Is there a possibility that the bearings are in the frame and not in the link? Unfortunately it’s not showed without the cover.
« Last Edit: December 23, 2021, 05:47:32 AM by Stef Biggel »

JJJ

FS830 links
« Reply #1122 on: December 23, 2021, 07:15:44 AM »
JJJ, look to this:
https://chinertown.com/index.php?action=dlattach;topic=3018.0;attach=7199

Is there a possibility that the bearings are in the frame and not in the link? Unfortunately it’s not showed without the cover.

Does look like the bearings are in the frame there, but then I don't understand the eyelet design - why they are so big, and why the bolt heads are so big.

sips56

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1123 on: December 23, 2021, 08:15:01 AM »
start a new thread gents, we have our hands full with the AM831 in this thread  ;)

JJJ

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #1124 on: December 23, 2021, 10:08:46 AM »
start a new thread gents, we have our hands full with the AM831 in this thread  ;)

Yeah, let's continue here: https://chinertown.com/index.php/topic,3018.45.html

Probably some of the guys can tell us about the links.