In a message dated 1/16/2003 11:16:40 PM Eastern Standard Time,
kasha.lists@cox.net writes:
>
> OK, so I have to ask. Why did they put that groove in the tops
> of the teeth? My chain zzzzing'ed on me the other day and it is
> not a nice thing to have happen. Is there a chain that will be
> less likely to do this (I am running the modern sram chain)?
>
>
The profiling of the teeth was done to help chain pick up. At 1972 Schwinn Factory School we were instructed to do two things to aid in the tough shift -- the one to the largest sprocket. We were to bevel the large sprocket's teeth on the wheel side of the fw (no need to remove sprockets,just to remove the fw from the wheel W
If this didn't help, we were told to bend the last part of the outside upper tab on the derailleur to help 'throw'the chain over the last sprocket.
(Sheldon and lexicographers - these shoiuld be sprockets or cogs? I say sprockets)
In other 'Schwinn School techniques', we were taught how to balance the two springs on the Gran Turismo campag derailleur for better (in many a shared opinion- less poor) performance.
Other kinks were to take a perfectly good Campy hub and program some slop so that when the skewer was toghtened, the cone adjustment would be perfect then As recently as2000 at the USCF mechanics' school at the OTC they made a major deal about using a pair of dummy dropouts kept in the pro toolbox and skewer to adjust front and rear cones.
Larry Black
far from perfect
snowy Woodbine, Md.