Bicycle Mechanics - that annoying sound

so i have a 62' schwinn cruiser with its stock 1pc cranks set and a single speed bendix "redline" coaster brake whell on the rear, also original. now i have rebuilt the hub like 5 years ago and the bottom bracket, since putting low miles on the bike. the other day, i noticed a rubbing or scraping sound, kinda faint but definatly making itself notice when i pedeled, but not when i coasted. i hear it from beneith me, maybe the bb or rearhub once per one revelution of the cranks and i first thought it was a rubbing chainguard, but it wasn't. i also rebuilt the bb again, inspecting the bearings and races b4 i repacked it and buttoned it all up, but the sound persists.

now, i have about ruled out the bb and wondering if this sound could be originating from the rear bendix hub? around the time i began to hear the noise, i then coasted and when i resumed to pedel, i had a split second of "neutral" before the driver in the hub engaged to power the bike. it was the only time it happened, it was brief and hasn't hapened since, even under heavy touque of "standing on the pedels" up hills.

what do i check next? i don't get easily stumped, but this one has got me. my next move was to find a doner rear wheel from another bike and test ride with it to see if the problem goes away, in which case it would have been the rear wheel at fault. the chain is cleaned, lubed with little milage and was a high quality bought at a LBS years ago. thanks in advance.:crash:

It could be from the rear hub, but I'd start my field-taxonomy with the chain. How long has it been on the bike?

the chain has been on the bike for about 5 years, parked and unriden up untill last july, at which point i rode it like 6 miles a week for about a month, parked it till a few months ago and put on about 6-10 miles aweek. all that time, this was one of my quietest bikes with no issues. just in the last few weeks it has made that rubbing sound when i pedal.

the bb has been gone over so much that i almost rule it out. if i do my rear wheel swap from a doner bike and the problem remains, then i will replace the chain and see what that gets me. of still rubbing, i will replace the bb bearings cups, balls and races. and with all points of physical external or obvious rubbing checked, if it is STILL rubbing, i will deem the bike haunted and repark it.

Don't ignore the pedals, and they're easy to check if you have a spare set.

Richard

good point europa. i slightly loosened up the bearing cone on the bb, but not too much as to create "slop" in the crankshaft last night and rode it to work this morning. most the way there i didn't hear the sound but on the way home i did, but not as loud. i noticed today that it does it (and its more like a muffled ratchet sound) when my right foot is between 12 o'clock and thru the down stroke to about the 4 o'clock position when im pedeling. when mashing up a big hill or standing on the pedals it goes away or if i put about only 20% power to the pedals.

i still got some sun light outside so i'm gonna try to swap out the pedals and see where that gets me.

i had this a while ago on my bmx but it was more of a squeak. I just lubed the threads in my pedals and that done the trick :) dunno if this helps?

FIXED IT!!!

so i swaped the pedals out from my 89' huffy gv cruiser and also loosened the rear wheel bearing cones just enough to give the wheel a hair of free play or wiggle room if you will, but not excessivly. coaster brake hubs are supposed to have a hair of free play, right? anyways, i got on the 62' schwinn and went for a test ride, actually a 5 mile test ride and no sound. sure i could pick out other ocd tiny sounds, but i can live with that. woulda been a longer test ride, but my partly cloudy skys turned to sleet about half way thru. really fun ride, but im a bit wet now.

thanks for the help.