Question: about older Campy Record RD, noises, adjustments, choices

I am resurrecting a '72 Bottecchia, one of the higher end models I'm
told (paid 10 bucks to a guy in the neighborhood). 5 gear freewheel,
Record RD/FD, lots of fun stickers in Italian, espousing national and
world champs (campione del mundo) inthe 60's.

Did yer basic clean up, repack bearings, and it is looking and riding
pretty good.

This is my first campy-equipped bike (was always a Suntour guy in my
youth). I notice that there is a noise that originates from the rear,
likely in the pulley wheel area... sort of a soft but consistent
bum-bum-bum mumbling when in most any gear -- but especially in the
lower gears as the chain passes thru. As this age, the pulley wheels
look somewhat worn. would worn pulley wheels cause this sort of bum-bum
noise? OR am I looking at a bad chain? RD seems to be well aligned.
Just looking to determine what nees to be done as I don't want to just
REPLACE everything.

The largest cog on the freewheel is a 32T! I think I do need to adjust
the B-screw (?) to draw the RD back a bit for clearance. Is there any
website on the net with pics and info on adjustment for these older
Campy changers?

Thanks for any and all help!

Mark

Mark E wrote:
I am resurrecting a '72 Bottecchia, ...

I notice that there is a noise that originates from the rear,
likely in the pulley wheel area... sort of a soft but consistent
bum-bum-bum mumbling when in most any gear -- but especially in the
lower gears as the chain passes thru. As this age, the pulley wheels
look somewhat worn. would worn pulley wheels cause this sort of bum-bum
noise? OR am I looking at a bad chain?

I don't know anything about old Campy stuff. But I resurrected an old
Motobecane a few years back, and it had a very similar noise. Well, it
was more of a vibration that I felt through the pedals rather than heard
with my ears. It was caused by a worn chain. I pulled the chain,
measured 12 links at much more than 12", replaced the chain and
freewheel, and the bum-bum-bum was gone.

--
Dave
dvt at psu dot edu