Can you guys recommend  if this is the bottom bracket I want for this frame?

SHIMANO XT BB-MT800 Bottom Bracket BSA Threaded, One Size https://a.co/d/gGSAvLJ

Or is this one correct?

Shimano Bearing Set BSA bottom bracket MTB Hollowtech II for Deore SM BB51 / BB52 by Shimano https://a.co/d/3RX5OFY

MTBKeo- what seatpost are you using?

Cybsrce- were you able to get your seat post in all the way? What brand are you using?

I was just gonna go Brand-X. I have one on my other bike and love it.

Thank you for the replies, guys. It is really helpful.

Well I jumped in and took a chance. It was only $277. How could I pass it up?

$320 with free shipping seems too good to be true. I can wait for delivery no problem if it's legit. I don't want to get scammed, though.

I'm glad I found this thread. I've been thinking about replacing the AM831 I have. I like how it rides but I have terrible creaks I can't seem to get rid of, and I don't want to keep throwing money at it chasing them.

This could be a good cheap replacement. Cyber, where you able to port everything over from your other frame? Besides the bottom bracket of course. The only thing about this frame that is concerning is the short reach. 450mm is rough. Maybe with the slack seat tube it's not bad? How tall are you Cyber? I would be on a 19" 29er also.

Please  give more impressions whenever you guys have them. Thanks.

So I finally got around to chasing my creaking sound today.

When I took the rear wheel off, I noticed the bolts on the rear linkage didn't look right. I'm talking about the very bottom ones closest to the rear axle. It looked like there was a tiny gap at the bolt on the drive side. With the rear wheel off, I could see it moving a bit when moving the rear triangle. I couldn't see that movement with the wheel on. I gotta say it was a pain finding an Allen key to fit in that little gap to adjust it. After three trips to the hardware store I got one that worked, but I think it's not the right size still (probably need a metric sized key). When I finally got an Allen key that worked, it was definitely loose. Really loose. Even the non-drive side was a bit loose. I tightened both as best I could with an Allen key that almost fit. I was pretty pumped to try it. Put the rear wheel back on and gave it a shot....the creaking was still there. Sonuva!

So I started looking at other things that could be loose. I figured I'd try the other pivot of the lower linkage. Not the one I just did, and not the one where the shock connects, but the one by the bottom bracket. When I found the right size key...son of a bitch it's a bit loose too. I tightened it and gave it a ride....silence! No creaking! I even it took it to a rocky area with some short steep uphills. No creaking. Perfectly quiet. I'll give it a real test on a full trail when I can (it's supposed to rain tomorrow), but I am so happy now. I was thinking I could have a crack somewhere in the carbon. I was wondering if I was going to have to buy the new rear triangle. I'm super pumped about the bike again. Between no creaking and JJJ's fix, I can't wait to ride this thing now.

Some of you guys were dead on with your assessments on what was causing the creaking.  Thank you all for pointing me in the right direction.

One question, anyone know what torque settings this pivot should be adjusted to? I had my wrench set to 12 or 14, and I think I went a bit tighter than that. What should it be? Thanks again guys.

Although you are mentioning some bearings I don't ever recall seeing at some of the pivots.

Hopefully that video works. Anyone have any idea what could be causing  this awful sound?

So it looks like it's not the bottom bracket causing the creaking sound. I redid the bolts at the upper part of the rear triangle. When I did I sat on the bike and heard the creak. When I did this the cranks were off the bike. So it looks like I'm totally wrong where the creak is coming from. I took a video of the creaking. Anyone know if we can post quick videos on here,?