Upgraded from an old 7 speed system to a new 10 speed system 2 months ago. The old system pretty much was junk as a new chain would only last 3 months, if that long, before it started skipping all the time. I knew the chainring had to be junk since I replaced the cassette a couple of years ago and hadn't ridden the bike much since I replaced the cassette. Also, I had no use of the front shifter. I decided if I was going to replace anything it would be the whole thing I would replace other than the frame, front wheel, fork, that kind of stuff.
I did have one other problem at the time before I replaced everything and that was an annoying clicking/creaking sound whenever I went to stand up and pedal as I climbed up a hill.
I replaced everything, mostly Shimano 105 except the crank which I went with an SRAM S300. I got everything put together and had the first two days of riding with the new system in semi wet conditions, it had rained early in the day and the pavement was still wet. Everything seemed fine. Finally got around to riding it the third day with nice weather and at first everything seemed fine then toward the end of the ride, when the going got going uphill the clicking/creaking noise popped back into system. This noise continued on and seemed over time to do nothing but get slightly worse/louder with the passing miles.
I've taken the bottom bracket apart three or four times now in the past 2 months since I made the upgrade, including an hour or so ago, and regreased everything and each time I go back out to ride it again the noise still remains...especially the new noise which is much worse.
Now it gets much worse. After I had taken the bottom bracket apart the last time and put it back together the noise did seem to die down in the intensity level but it is still noticable. About 3-4 days later a new noise started showing up on occasion. It sounds more like a piston knock, like walking on a vinyl tile floor with cleats on. It's always in the same part of the pedal stroke. I can unclip from the left pedal and continue to spin with the right pedal only and the noise disappears. As long as I'm putting any kind of pressure on the left pedal the noise is there unless I stand to climb. If I stand to climb the noise either completely disappears or diminishes dramatically until I shortly after I sit back down again. I tried putting on an old platform pedal I had laying around this morning...I know my Look pedals have a lot of play in them, and that didn't make any difference, still the same old noise.
At times as I spin I can feel what does seem like play. I'm not sure if that is coming from the crank/bottom bracket, or if I'm feeling play from the pedals.
Is there any reason that an old system noise would carry through to a new system. Can something in the frame(old early 90s Cannondale) cause something like this to occur. The only two things I haven't replaced, completely, is the pedals and frame. The bottom brackets is tight and has no play in it at all. What else could be causing this irritating noise. I'm almost to the point of hating to even ride the bike because of how darn noisy it is right now and everything I've tried makes no difference.
Also as I think about, before I hit the submit button. The original noise did have one characteristic to it that I haven't really had the opportunity, other than this weekend with Hurricane Irene...no thank you, to try out with the new noise. If I ended up getting caught out in the rain or was riding in real humid conditions, the noise would have the tendency to disappear until things dried out. Yeah, I know, sounds like bearing/grease problems. Like I said I've taken the sucker apart and regrease 3-4 times in the past two months with no difference being seen.