Author Topic: The Shiny New AM831 Group Buy (A) Thread!  (Read 175544 times)

Snacks

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #420 on: August 28, 2021, 06:24:06 PM »
Why do you say only the dpx?

Similar to coils the width of the opening to the rear mount is not big enough for the other two to fit.

riding_truckee

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #421 on: August 29, 2021, 12:27:05 AM »
[UPDATE: please ignore this post, the issue was caused by a defective derailleur and my silly mistake!]

I got my frame yesterday and built the bike today, but I run into a fairly big issue:

The derailleur hanger does not stick out far enough, so my 1x12 Eagle cannot engage the smallest cog.

Has anybody successfully mounted a SRAM 1x12 on this frame yet?

It is possible that I'm missing something obvious, but from what I can tell, the outer side of the hanger, where the derailleur bolt screws in, seems too close to the center of the bike, by about about 3 to 4 mm.

Even with the high-limit screw completely loose, the derailleur pulley wheel only aligns with the 2nd cog, not the 1st.

A hacky solution would be a thick spacer between the derailleur and the hanger, but that would result in the derailleur bolt being only half engaged, which is very weak.

I hope that I'm missing something obvious ...

« Last Edit: August 29, 2021, 11:03:45 AM by riding_truckee »

Snacks

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #422 on: August 29, 2021, 01:07:52 AM »
I got my frame yesterday and built the bike today, but I run into a fairly big issue:

The derailleur hanger does not stick out far enough, so my 1x12 Eagle cannot engage the smallest cog.

Has anybody successfully mounted a SRAM 1x12 on this frame yet?

It is possible that I'm missing something obvious, but from what I can tell, the outer side of the hanger, where the derailleur bolt screws in, seems too close to the center of the bike, by about about 3 to 4 mm.

Even with the high-limit screw completely loose, the derailleur pulley wheel only aligns with the 2nd cog, not the 1st.

A hacky solution would be a thick spacer between the derailleur and the hanger, but that would result in the derailleur bolt being only half engaged, which is very weak.

I hope that I'm missing something obvious ...

the green bike that eddy posted looked like it was running 12 speed NX on there. if you have the cable attached already maybe check cable tension. does it make it to the 1st cog if you remove the cable from the rear derailleur ?

edit: its on page 27. i cant tell if that 1x11 speed or 1x12 speed NX
« Last Edit: August 29, 2021, 01:09:47 AM by Snacks »

Thrill21

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #423 on: August 29, 2021, 07:26:33 AM »
I got my frame yesterday and built the bike today, but I run into a fairly big issue:

The derailleur hanger does not stick out far enough, so my 1x12 Eagle cannot engage the smallest cog.

Has anybody successfully mounted a SRAM 1x12 on this frame yet?

It is possible that I'm missing something obvious, but from what I can tell, the outer side of the hanger, where the derailleur bolt screws in, seems too close to the center of the bike, by about about 3 to 4 mm.

Even with the high-limit screw completely loose, the derailleur pulley wheel only aligns with the 2nd cog, not the 1st.

A hacky solution would be a thick spacer between the derailleur and the hanger, but that would result in the derailleur bolt being only half engaged, which is very weak.

I hope that I'm missing something obvious ...

Start over and work backwards, take your shift cable and take it right off the derailleur - make sure your high speed adjustment and low speed are where they should be in relation to the high and low speed cogs. Something does not sound right. It would be an absolute shock if this is frame related which I don't believe it is.

riding_truckee

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #424 on: August 29, 2021, 08:17:38 AM »
Start over and work backwards, take your shift cable and take it right off the derailleur - make sure your high speed adjustment and low speed are where they should be in relation to the high and low speed cogs. Something does not sound right. It would be an absolute shock if this is frame related which I don't believe it is.

I checked all of these. Later today I'll take a picture with the cable off (still hoping I did something wrong).
BTW, the issue (if any) is not with the frame, but with having the wrong hanger.
For example this https://www.ebay.co.uk/itm/291799753019, which looks similar to the one that came with my bike, seems to have a bulge that could be sufficient to offset the derailleur.

zilcho

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #425 on: August 29, 2021, 08:49:46 AM »
I checked all of these. Later today I'll take a picture with the cable off (still hoping I did something wrong).
BTW, the issue (if any) is not with the frame, but with having the wrong hanger.
For example this https://www.ebay.co.uk/itm/291799753019, which looks similar to the one that came with my bike, seems to have a bulge that could be sufficient to offset the derailleur.

Keep in mind that the limit screws on Eagle are opposite of the location they're setting, so smallest gear is going to be the screw closest to the bike, not farthest out.  Also check if the hanger is bent out of alignment.

cybrsrce

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #426 on: August 29, 2021, 08:53:30 AM »
I checked all of these. Later today I'll take a picture with the cable off (still hoping I did something wrong).
BTW, the issue (if any) is not with the frame, but with having the wrong hanger.
For example this https://www.ebay.co.uk/itm/291799753019, which looks similar to the one that came with my bike, seems to have a bulge that could be sufficient to offset the derailleur.

Picture would probably help us a little.
Is it an XD or HG hub body?
Can you manually move itto the highest gear with the cable disconnected?
This may sound silly but did you use the included XDR spacer when you installed the cassette?
Is the hanger bent?

riding_truckee

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #427 on: August 29, 2021, 11:01:11 AM »
OK, everything is fine: sorry for the noise!  :(
My brand new GX derailleur had a metal chip stuck in one of the hinges which prevented it from returning to the end position!

This would teach me to do bike work late at night and then post my mistakes to a forum!
In the process, I also checked the design of the hanger against SRAM specs (https://www.sram.com/globalassets/document-hierarchy/frame-fit-specifications/mtb/2021-mtb-frame-fit-specifications.pdf), and it is totally in spec!

sorry everybody!

darius72

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #428 on: August 29, 2021, 11:10:44 AM »
Nice to hear this! now post a photo of the newbuilt bike, and a part lists if you feel like. A lot of people here are finalizing their projects

FlaMtnBkr

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #429 on: August 29, 2021, 04:06:14 PM »
Can people also maybe verify some of the measurements like the front and rear shock brackets? As well as a seatpost insertion depth and frame size? I've seen one person say 10" (254mm) and looking back it looks like he ordered a small and medium frame so not sure which was measured? But based on published seat tube length, even if it was a medium frame, a large would have 37mm more for a total of 291mm, which for me gets me close to a 210 OneUp dropper. But would like to get some verification before ordering if possible. And I figure the more measurements we get (and the frame size) the better for everyone ordering parts.

Someone said that the 8x30 mounting hardware is on aliexpress but I'm not finding much. I saw one listing but they were out of that size and haven't had much luck elsewhere either except for some that are way overpriced. A link would be great if anyone has found it in stock!

I've also seen others ask about a build list so I'll work on mine to post and will try to include links to what I actually purchased if I didn't have it already.

scourge

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #430 on: August 29, 2021, 05:06:28 PM »
Yeah this is my first bike build and I have no idea on shock mounting hardware.


cybrsrce

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #432 on: August 29, 2021, 07:42:29 PM »
Did any cable hole plugs come with the frame?  I will only have the rear brake hose running through the frame so I'll be looking to close everything else up.  Jagwire makes a couple different sizes if none are included.

riding_truckee

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #433 on: August 29, 2021, 09:25:32 PM »
Attaching a picture of my finished build. This frame size is "S".
Only the bottom cage is missing and I haven ridden it yet, apart up and down the street to tune suspension and saddle height.

Some interesting parts of my build:
  • assembling the lower pin of the rear shock was challenging, as I could not find any position of the rear triangle that gave me enough clearance to remove the bolt. I ended up unscrewing the top hinge form the frame (removing the 2 bolts just under the saddle). Not sure if that was the best choice because repositioning the hinge wasn't easy, but it worked
  • my mounting hardware for the shock was M8x30 and M8x22.199. The x30 (top) fit perfectly, the x22.199 was loose: i measured 22.86mm for the opening. Rather than ordering a new one, I 3d printed 2 spacers, which seem to work well
  • My shock is a Fox dpx2. It fits pretty well, but the access to the air valve is tight, I can barely connect my pump to the valve.
  • I used a Fox36 fork, that barely clears the frame, after using the 0.5 degree angle spacer from Reverse, which is about 10mm tall. BTW, jham asked about installing the angle spacer: it is an "interference fit", just like a standard crown race. I used a piece of PVC pipe with id of about 1.5" to push it down, with the help of a rubber mallet

As for my component list, most of them are reused form other builds or both 2nd hand:
  • fork: Fox36 w/ GRIP2 damper. The damper adjustments barely clear the frame even after adding the angle spacer
  • rear shock: Fox dpx2, see my comments above for the mounting hardware
  • drivetrain: SRAM Eagle GX, with SRAM DUB 89/92 pressfit bottom bracket
  • wheelset: Lightcarbon 350MB-AD938-Race, shared with my other frame
  • breakset: Shimano M8200, which I got new at a good price form a seller on Pinkbike. The rotors are generic from Amazon (https://www.amazon.com/gp/product/B082NVF3TD/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1)
  • dropper post: and old Tranzx 31.6x140. I pushed it all the way down the downtube.. and it still might be too high, I need to double check it, but I have not measured the insertion depth
  • saddle: a SDG Radar.. I have no idea of how good or comfortable it is, I got it at a discount because my other SGB Bel Air failed, but I have to say that I like a lot my WTB Volt on the other bike
  • stem and Carbon Handlebar: inexpensive from Amazon (https://www.amazon.com/gp/product/B0916YJ81R/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1 and https://www.amazon.com/gp/product/B07JPF4T71/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1)
  • headset and Sitclamp: I used the one that came with the frame. The frame also came with 4 cable hole plugs, for the larger holes by the bottom of the downtube. They are rubber, not easy to install. Not sure if they will hold
  • missing: chainstay (and maybe downtube) protection. I have something that might work, but I haven't tried to install it yet.

I hope this is helpful to others..
« Last Edit: August 29, 2021, 11:37:26 PM by riding_truckee »

bbr

Re: The Shiny New AM831 Group Buy (A) Thread!
« Reply #434 on: August 29, 2021, 10:08:31 PM »
Finally a full build pic. Nice build. Your dropper cable housing will rub down on your shock. What was your solution for housing knocking inside the frame and rear swing arm?

Any idea for an elegant rear mud guard? I have not figured one out.

Hopefully you guys have cycle the rear suspension  movement for any binding. The top link at the top tube  might need a 10*16*1 spacer bushing. Very well depend on the frame tolerance.


No pic from me as mine is generic black build. Pretty much the same looks just all black.