I'm a bike novice, I recently dug out my 10yr old mountain bike. Its a reasonable bike Marin Muirwoods. My problem is when I am pedalling hard and the pedal is at the apex / top and I push down hard it just slips. There is no resistance. It is usually accompanied by a metallic crack. I got the rear cannister? and chain replaced but to no avail. Dont think it is slipping into a different gear either. Could it be the crankarm? A couple of days ago I was standing up pedalling hard to get some speed and suddenly there was no resistance and i ended up over the front of the bike. Fortunately a kindly pedestrian dragged me off the road. Any help much appreciated
bicycle problems Any monkeys good with the spanner and know a bit about bicycles. I have a problem that needs urgent fixing to prevent me from going over the handlebars a second time.