Hey everyone,

Lately I have been having an issue where when my left crank arm is at 270 degrees i hear a creak when i'm riding. Any idea what this can be. It only occurs at this one point per full rotation of the crank arm.

Thanks

Simple thing first: remove both pedals and lube the threads, then reinstall tightly.

-I am not a mechanic-

I've had a few bikes do this to me. I have fixed every one by tightening the crank arms or if that doesn't do it remove the arms and grease the square drive and bolt when you put them back on.

Grab the crank arms(not pedals) one at a time to determine if one or the other, perhaps both are moving, if not check the pedals, and finally if there is play in the BBC bearings, or cartridge. I suspect it's probably the bb bearings. You will need bike specific tools to work on any of the above mentioned components. Good luck!
Cheers

Check the chainring bolts, too.

And the saddle clamp on the seat post. And your cleats (if any). And even your stem where it clamps the handlebar. It can be astonishing where these sounds seem to come from and where they actually come from.

I had plenty of issues with that creaking... Sometimes it was saddle, and sometimes BB.

If it's a saddle - lube the rails where they go inside plastic base of the saddle
With BB, wet and sand will do it... Take BB out, remove all the dirt/sand. Put BB back, and use some good, waterproof grease. I use cheap marine grease. Make sure all the bolts are tight...and you should be ready to go.