either your engine is locking up or the starter isnt turning... it would be a spark issue if the bike wasn't firing up after it turned over and over . Its not turning over from what I am hearing. it should be turning over for like 15 to 30 seconds straight and it sounds like its being hung up from starting. so starter clutch? starter motor? I dont even hear the starter free turning.

show me a video of you just holding down the start button so i can hear the engine turn over for an extended period of time. if not... its not fuel or spark... its the starter motor.

Yeah the starter doesn't turn. It does sound like the engine locking up though. I almost hear a metal running sound when I turn it off. I will record a video when I get the chance! It runs well other than trying to start it hot

I would say you need a new starter then.... what perplexes me is the bike when allowed to cool down.... it then will fire up. I Told Chris @ Rc scooters about your problem. He said he would jump on tonight and look over whats going on.

when it locks up like the video.

1. volt meter to the battery and check voltage. if drops to 10.5v when u hit the start button it might 50/50 chance spin or just click but if spins, definetly will not start cuz the fuel injection systems needs more voltage. (this doesn't sound like your issue but always check battery health and this is a good method, no kick starter so don't get stranded by bad battery)

2. if u think it's starter, tap on it with a wrench and if turns over then it's starter. if still doesn't turn, try boost it with car battery or booster battery, if tuns over then it's starter. since it's stock 125 just get a stock starter, if u plan to mod the motor in the future then can get a aftermarket starter.

3. turn off engine and makes noise is starter clutch assembly and cvt. i would suggest servicing it. clean it and relube it. change parts thats worn. possible previous owner didn't service it or been sitting too long.

https://youtu.be/AoPA7QxM9IE

This is it after riding and trying to immediately start. I recorded a longer video to maybe give you a better idea?

that's starter clutch.

remove the cvt parts to access the starter clutch and that large starter gear. also need to service the idle pinion gear. sounds like it's dry and also starter clutch is worn. has 4 small rollers inside the starter clutch if got flat spots or scratched up then change it. also change the large starter gear too, pretty sure it's scratched up by the 4 rollers.

http://www.boats.net/parts/search/Yamah ... parts.html

#1 and #4

Here's a few more videos for reference
A cold start that wasn't that smooth
https://youtu.be/CC15GuzyZtY

A few with the cvt cover off. One shows the starter gear turning when turning off the engine! Idk if that's normal? Prob ordering the parts soon. Let me know if I should be looking out for anything? I think I need a new belt too.

https://youtu.be/tnvWUn_U9ss

And

https://youtu.be/yCQRb_DAeOY

Everything i saw looked normal to me. all the videos showed a start. i want to see what we are looking at when you try to turn it over and it wont fire. all the rest of this stuff is of no use to figuring out how to help you. a doctor needs to see the bad heart rate recordings on paper not the ones where your heart is fine. lmao! hit us up with the videos of the bike not working and film that. then its an easy confirmation.