Author Topic: The Shiny New AM831 Group Buy (A) Thread!  (Read 128192 times)

Maffly

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #795 on: October 26, 2021, 07:05:23 AM »
Thanks for posting the video. Hope that’s before the shims because it looks unrideable. I am still waiting on my frame to ship and have asked Eddy about the issue. Hopefully it is being addressed. Don’t see these frames continuing to sell if not. I know I would not have ordered after seeing all of these concerns. Very interested in more video post fix.

cybrsrce

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #796 on: October 26, 2021, 07:40:18 AM »
Thanks for posting the video. Hope that’s before the shims because it looks unrideable. I am still waiting on my frame to ship and have asked Eddy about the issue. Hopefully it is being addressed. Don’t see these frames continuing to sell if not. I know I would not have ordered after seeing all of these concerns. Very interested in more video post fix.

That is with the shims I made from a gallon water bottle, probably .5mm - maybe less.  I believe the issue is like FlaMtnBkr said, the bolts are just a few mm too long and bottom out in the back of the linkage.  The "proper" fix is probably shorter bolts, whether that is a redesign or a cut and chamfer, but I noticed with the bolts out it is pretty far from the linkage.  Pinching it in may actually contribute to the stiffness and I may make it worse by adding larger shims, we'll see :)

After about 10 hours riding with the shimmed setup I don't feel like it is squirming or losing traction.  That may just be me getting used to it or simply paying more attention to suspension tuning than flex.

I don't know anybody with a current generation Santa Cruz to see how much flex is acceptable, I would like to compare.

threeathan

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #797 on: October 26, 2021, 09:22:57 AM »
I see, thanks for the video, really concerning especially it being a china frame. Do update us if you are able to do any other things that may try and fix and stop the flexing.

Hope to hear what eddy says when he replies Maffly. Do keep us updated thanks again.

JJJ

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #798 on: October 26, 2021, 09:33:13 AM »
That is with the shims I made from a gallon water bottle, probably .5mm - maybe less.  I believe the issue is like FlaMtnBkr said, the bolts are just a few mm too long and bottom out in the back of the linkage.  The "proper" fix is probably shorter bolts, whether that is a redesign or a cut and chamfer, but I noticed with the bolts out it is pretty far from the linkage.  Pinching it in may actually contribute to the stiffness and I may make it worse by adding larger shims, we'll see :)

From what I gather, there are only two in the group that have the problem. I have no issue and the vast majority of the group probably doesn't either, because we don't post when there is no issue! Mine definitely doesn't flex like that!

The shim solution doesn't sound great - is it so hard to mill some mm off the bolt? How does the incriminated bolt compare with the one on the other side?
« Last Edit: October 26, 2021, 09:36:53 AM by JJJ »

Maffly

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #799 on: October 26, 2021, 10:50:56 AM »
Good to hear that the flex is not an issue on your frame. Been following cybrsrce and his badass build. Scary to see all the time, effort and expense go in just for an issue like that to happen.  The bolt being too long or running out of threads is one possibility for sure and the most hopeful one. I will let you all know if Eddy responds to the concerns. Guess we are all sort of gamblers and problem solvers or else we wouldn’t be taking this on

Snacks

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #800 on: October 26, 2021, 10:59:47 AM »
From what I gather, there are only two in the group that have the problem. I have no issue and the vast majority of the group probably doesn't either, because we don't post when there is no issue! Mine definitely doesn't flex like that!

I have the issue as well. Mentioned in cybrsrce's thread . Cut some plastic shimas as I couldn't find anything to use that would work at the hardware store.

I hope it's not a common problem but realistically not many people who have bought the frame chime in regardless of if they have issues or not. 2 of 2 people with build threads have the issue and like 3 out of the like 7 people who have the frame and regularly contribute have the issue. So I wouldn't brush it off as a non issue for most.

cybrsrce

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #801 on: October 26, 2021, 11:21:54 AM »
From what I gather, there are only two in the group that have the problem. I have no issue and the vast majority of the group probably doesn't either, because we don't post when there is no issue! Mine definitely doesn't flex like that!

The shim solution doesn't sound great - is it so hard to mill some mm off the bolt? How does the incriminated bolt compare with the one on the other side?

For the safety of the linkage threading you should use a chamfering tool, but yes taking 2mm off would seem to be the best solution.  I don't want to mess with the bolts because they're not something you can just run out and buy, I'll play that game when I get an extra set.  Both sides are shimmed at the moment but there doesn't seem to be any play between the linkage and the rear triangle without the shims, just more flex.  Washers were $5, it was worth it to test.  I have washers and shims everywhere on this frame, what is another set :)

scourge

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #802 on: October 26, 2021, 12:02:33 PM »
Whoa! My bike does not do that

cybrsrce

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #803 on: October 26, 2021, 01:09:44 PM »
Whoa! My bike does not do that

There is also the possibility that I am just a gorilla, it would be good to see what others bikes do.  Flex your rear triangle, a Chinertown internet challenge...

Maffly

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #804 on: October 26, 2021, 02:15:22 PM »
Looks like it moves quite a bit without much effort. Wheel flex seems significant too but hard to tell. My buddies Yeti looked just like that when it needed a rebuild. Good as new with bearings replaced. Tolerances don’t have to be off by much to cause problems. Like the idea of the video challenge.

emu26

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #805 on: October 26, 2021, 03:39:15 PM »
Wow, that is a lot of movement.

Has anyone spoken to Eddy about this so that they are at least aware of the issue.

Maffly

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #806 on: October 26, 2021, 03:59:51 PM »
I emailed him. Responded that he got it but no details

JJJ

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #807 on: October 26, 2021, 04:02:34 PM »
With thin shims in it is considerably better than it was.  I have a variety of different nylon washers coming today so I am going to experiment with 1-3mm on each side.
A video of the flex.

Actually, it's more the wheel that flexes than the rear triangle, and that entirely depends on the wheel build. Try gripping the rear axle instead of the tire.

cybrsrce

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #808 on: October 26, 2021, 04:35:04 PM »
Actually, it's more the wheel that flexes than the rear triangle, and that entirely depends on the wheel build. Try gripping the rear axle instead of the tire.

I'll try to get an angle where the bike more supported and the movement stays in the triangle.  If you don't focus on the tire you'll see the seat tube moving more than the seat stays.  I'll put an axle with a handle on and see if it is any different but the wheel flex won't make the seat stays flex.

Eddy-haideli

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #809 on: October 26, 2021, 09:35:43 PM »
Sorry that i have not got the email for the question you mentioned, can you show us some pictures by email.

Eddy@haidelibicycle.com