Nasty noise

I (well, my CAAD8) has developed a nasty creaking noise... It came on during a 17 mile ride and gradually got worse.
It seems to only really happen when I push hard with my left peddle. How do I tell if it's peddle related or bottom bracket related?
I'm a bike tech newbie really, but feel I should learn rather than stuff it straight into the LBS
It seems to only really happen when I push hard with my left peddle. How do I tell if it's peddle related or bottom bracket related?
I'm a bike tech newbie really, but feel I should learn rather than stuff it straight into the LBS
'12 CAAD 8 Tiagra
0
Posts
I'd grab the crank arm and give it a good hard wobble (fnarr). If it's the BB it would usually rattle about a bit.
One tip I saw on bicycle tutor is to put the thing on a bike stand and press your ear up against the nose of the saddle (seriously). The bike frame delivers any vibrations/grinding to your ear. Try just spinning the cranks and you might hear a grinding.
I'd also look at the BB cup to see if it's all the way into the BB shell.
I used the park tools website to suss out how to do all this the first time i needed to do it.
Kona Jake CX
Cervelo P5
Pedals are easy to take off with a hex key of... (er, can't remember what size, but it's at the back of my tool bag downstairs). Please don't tell me you need to got to the LBS to do that?
Kona Jake the Snake
Merlin Malt 4
I think I'll whip the pedal off and see if I can replicate the noise in the garage and then take it from there.
I doff my cap to you; I can never manage this (just round out the socket or shear the key), so rely instead on a pedal spanner. Perhaps I ought to get some copper slip.
If the crank is loose and comes off easily then the nut has come loose and the crank has been wobbling on the spindle of the BB. Every pedal revolution makes the problem slightly worse. 17 miles will have killed it. No amount of tightening the nut will tighten the crank to the spindle without it wobbling.
In my experience, in the battle of soft aluminium crank Vs hard steel BB spindle, the BB always wins.
Conclusion: New crank time.
FCN 4: Planet X Schmaffenschmack 2- workhorse
FCN 9: B Twin Vitamin - winter commuter/loan bike for trainees
I'm hungry. I'm always hungry!
Many a time I've developed a creak etc on the bike and would have swore it was coming from the drivetrain and it's ending up being the seat post or saddle!
<center><font><b>My Kinesis</b></font></center>
Chapaeu.
Voodoo Bizango - 2014 - Dead - Hit by a car
Vitus Sentier VRS - 2017
Planet-x Scott
Rides
But if they did make a noise, it might be that the pedals don't get on with the new bike. You'd need another new bike as a control to check it.