Bicycle Mechanics - Are 2 micro-adjusters mandatory for proper index shifting?

Hello. I'm about to put SunTour Accushift 7 speed bar-end shifters on my wife's Austro-Daimler Puch Pacifica.

The bike does not have downtube braze-ons. I have a nice set of 7 speed bar-cons from ebay that I want to use with an accushift rear derailleur and a 7 speed Winner freewheel or 7 speed Powerflow cassette wheelset for 27" that I intend to have built.

I notice that newer bikes with brifters have the adjuster barrel on the rear derailleur and also at the headtube or down tube. Do you need 2 of these adjuster barrels, or can you get by with just the one on the rear derailleur?

I thought about using a down tube stop like this: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=018&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=280120317468&rd=1&rd=1

But if the mechanics in the house think I should have downtube adjusters, I may modify some downtube shifters that clamp on, and fit them with STI adjusters.

Thanks for your assistance with this retro project. :o

I've done it with no adjuster barrels. On 8 speed bikes.

The downtube barrel adjuster for the rear derailleur is not needed. The one located on the derailleur is plenty.

For index front shifting the dt adjusting barrel is necessary but your barcons will have friction shifting so you can easily do without it.

The downtube barrel adjuster for the rear derailleur is not needed. The one located on the derailleur is plenty.

For index front shifting the dt adjusting barrel is necessary but your barcons will have friction shifting so you can easily do without it.

Sweet. This is kind of what I thought. Using the indexed barcons ought to be fun.

Sweet. This is kind of what I thought. Using the indexed barcons ought to be fun.
All modern barcons provide index rear shifting. None of them provide index front shifting. Why? Dunno.

All modern barcons provide index rear shifting. None of them provide index front shifting. Why? Dunno.

why would you need indexed front shifting on a barcon? Friction is plenty fine.

+1 to an unequivocal 'no', based on my single experience...

When converting to indexed rear shifting, I mounted some dt cable stops with adjusters. But the plastic adjusting screws are balky, they turn with almost impossible difficulty, and I gave up on them.

The rear derailleur adjustment cable stop screw is all that is needed to adjust the indexing. The dt adjusters are for quick tweaking while riding. With the rear dialed in correctly, I have ridden several thousand miles with no further rear adjustment necessary.