On Mar 6, 8:52*am, HarryB wrote:
On Thu, 6 Mar 2008 06:40:02 -0800 (PST), Ozark Bicycle



wrote:
On Mar 6, 8:16*am, HarryB wrote:
I purchased an older used bike that is equipped with Paul Thumbies
shifters, a Shimano RD-M739 rear derailleur and a nine speed cassette.
I can't get the indexing to work properly (have tried clamping the
cable on either side of the screw) and wondering if that is because it
seems that the derailleur is an 8 spd one. It does shift ok across the
complete range of the cassette in friction mode.

If I need to purchase a new derailleur (because I want the indexed
shifting), would one like Shimano's RDM510A (that can be purchased
from Nashbar for $18) be a good choice? I need a long cage derailleur.

TIA,
Harry

Are you sure that the RH (rear) shift lever is a Shimano 9 speed
lever?

On the top of the lever it says, "9s Shimano" and has arrows for SIS
and FRIC. On the side is a sticker that says, "Compatible with RD-7700
(9s) & RD-7400 (8s)"

I assume that means it's 9spd index capable.


Yep.

Try:

http://parktool.com/repair/

click on 'rear derailleur adjustment' and follow the steps.