mountaindave 

I have two used sets of these and finally decided to put a pair on a bike. I spent all afternoon trying to set up a bike with full 6400 group except for the Sachs ErgoPower shifters. (I'm pretty sure I have a bent derailleur hanger, so that's giving me fits)

The most frustrating thing was trying to get the 8s shifter to shift to the lowest position. It was shifting for a while, then abruptly decided not to stay in the detente for the lowest gear. I tried both shifters and neither would hold the lowest gear. Tugging on the shift cable would pop the shifter out of the lowest gear. Any ideas?

Thanks for any help.

Fred Smedley

Do you have the Campy version of those shifters?

dsbrantjr

Rule #1 of troubleshooting: Fix what you know is wrong first.

Buying used shifters can be risky; there may be a good reason the previous owner sold them...

Andrew R Stewart 

So the Sachs Ergo levers are 8 speed BUT the cable pull is designed around Shimano 7 speed cog spacing and the Shimano rear der cable pull ratio. They are a real odd combo in this regard. So they will index well on a campy 8 speed or Shimano 7 speed cog set (both use the same 5mm c-c cog spacing) with either a Sachs or a Shimano der (of that era). But the Shimano 8 speed cog set uses a different c-c spacing (4.8mm IIRC) so after a couple of shifts there will be indexing mismatching building up.

But this mismatch is in the direction of the der moving further away from the cog set's center then the actual cog's center distance. The typical reasons for small cog chain jumping off and the chain's trying to shift to the second cog are- limit screws not set properly, bent hanger or der cage, pulley wheel w/o float, cable too tight (or miss set indexing), cable friction not allowing the der to pull the cable through is route from lever to der, Miss matched parts, cassette lock ring too large a flange diameter for small cog tooth count.

Additionally these Sachs shifters can be rebuilt and the index gear (the spool with the cable wrapping around it and the indexing detents on it) can be subbed with other campy ones. I have done this mod to convert the pointy hooded levers to campy 9 speed, be aware that there are different internal axle dimensions and the proper indexing gear can be hard to find and costly.

Lastly is that these levers do wear internally. They can get worn G springs, worn indexing gears (this is rare), broken spring carriers, gummed up pivots, rusted release thumb levers and more. Andy.

mountaindave 

Thanks for the replies. Here's more info:

1) These are 8 speed Sach-built Ergos
2) I used 7 speed spacers with an 8 speed cassette to get as close as possible to the 5.0 mm spacing, that helped a lot.
3) I have yet to rebuild either shifter. As usual, wishes didn't turn out to be fishes.
4) The gear that won't hold is the lowest gear, the final throw to the biggest sprocket on the cassette.

I have rebuilt three 8s STI's successfully, but after spending all afternoon futzing with setting the bike up, I didn't have the energy (or ablility to avoid the "you've been in the garage ALL afternoon" messages from "she who probably should be obeyed"). Perhaps old, gummy grease is giving me fits? I have the Campy instructions, I now just need to invest the time and see if that will work. Will a worn spring cause indexing problems like I have experienced?

Worst case scenario, I throw a set on my 7 speed bike and look super sexy.

Andrew R Stewart 

md- Thanks for the added details. I did misread the position on the cassette that the problem was at. However the largest cog position of problem does support the worn g springs possibilities. As the der parallelogram spring ramps up it's tension the g springs have a harder time holding their engagement with the index gear. As these early Ergo levers don't have the spring carrier with the post the carrier's chance to be broken is less, but not completely eliminated.

If I were you I'd overhaul the levers with a replacement of the g springs. But having done many it's not a daunting job for me. Andy (who has a sew uped bike with the first gen metal bodied Sachs levers hanging in the garage).

mountaindave 

Thanks, Andy. I have to dig through my archives to find a fellow BFer who offered a G spring for this gen, I don't think they are available anymore.

After disassembling a "non-serviceable" STI, I feel confident that I can get through a "serviceable" Ergo. I haven't seen the internals, but what you said about the G spring sort of makes sense: it's as if a pawl is not being held in place tightly enough to hold the last position. If that's what the G spring does, then both sets need replacing.