Hey guys I have a specialized mtb with the old oval chainrings and lately it's been locking up. When I start pedalling "hard" or faster the crank stops turning and then jumps forward a bit and generally is not very pleasant. Please note the wheels keep turning fine. Has anyone had this problem before? It's happened to me on another, thankfully cheaper, bike that was stolen a year before I built my fixie (which gives me no such problems) a couple years ago.
To recap, the pedals stop turning and then jump forward, stalling in a way, when I start to pedal harder, like up a hill or just on flat but faster. How do I fix this?
Thanks for any help! I really love this bike!