today i hit a tiny like 3 ft drop and when i hit the ground my cranks moved and suddenly became parallel to each other and can move freely without the other one moving, i tried loosening the crank arm with an allen key but it didn’t do anything, anybody know what’s wrong with it?
Sounds like you broke the shaft connecting the 2 cranks or stripped the crank arm to me.
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Is it a square taper bottom bracket?
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Looks very much like square taper. I’m guessing it’ll be something in the bb that sheared. For sure if it moves freely now.
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sounds broken…when I was young I would get the tools and take broken things apart to see what broke and then replace the part.
In this case it looks like you will need an 8mm allen key, crank puller and a Shimano bottom bracket tool for square taper cartridge bottom brackets.
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What they said. Sounds like a busted bottom bracket axle.
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I usually took thinks apart, but had a 50/50 success rate of getting them back together.
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And any parts left over were considered ‘options’.
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Weight reduction. I started the trend early in life.
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I likely have the square crank puller and possibly the Shimano BB tool if you want to play the home version of Bike Mechanic. I found it really useful to understand how things work and know how to fix things, but also understand that it’s not for everyone. When in doubt, bring to the shop. 
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i think i’m just going to take it to the shop because it seems like my bike is braking every week in a different place so i need to get that sorted out
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When you get your new bike, keep the old one and play around on fixing it up? Always nice to have a spare bike!
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Welcome to MTB! It sounds like you are throttling things as you should! Bikes and parts will
break. It is a good idea to get familiar with how to fix things because it sounds like you don’t hold back. You may need to take it to a shop but look at some stuff online. At some point you may need to buy some special tools but many of us have those and would be willing to share them and advice, because sometimes you botch repairs. It’s all part of learning.
That said, try to keep your body intact!
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yup! i’m taking it to the shop tomorrow so that’s good but i’ve been watching lots and lots of videos on bike maintenance/repairs so hopefully in the future i will be able to fix some things on my own
No doubt. It’s a tough sport and things happen. Hope it all works out and you are back out there soon!
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