Shimano A Type boss coversion index shifters
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Shimano A Type boss coversion index shifters
Looking for conversion parts to make a frame with Shimano Type A bosses accept index shifters, apparently I need the boss covers and 4.5 MM screws. They were apparently available for both 6400 and 7400 series shifters.
My other option is modifying the bosses, but seems like a last resort.
ShimanoSL6400-FAI.jpg
SL-7401-7FAI M4.5.jpg
My other option is modifying the bosses, but seems like a last resort.
ShimanoSL6400-FAI.jpg
SL-7401-7FAI M4.5.jpg
#2
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Good luck! There's quite a few threads on work around fixes and a few with just cussin'
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A commonly posted issue. There are multiple threads about this, with solutions ranging from hunting down the parts, modifying the keyhole shaped mounts and threading, and converting to brifter or bar-end shifters. I did the latter with my 85 Centurion Ironman.
Here's a list of related threads:
Modification: Old style Shimano downtube shifter mounts to later style - Bike Forums
Shimano 600 shift lever woes on a Centurion - Bike Forums
Do I have "B" Style Shifter Bosses? - Page 2 - Bike Forums
Shimano 4.5mm Type-A Shifters / Downtube Braze-ons - What are my options? - Bike Forums
Help Me Out With Shifter Boss Covers on This Miiyata 912 - Bike Forums
cable stops for unusual downtube brazeons - Bike Forums
Downtube shifter boss compatibility - Bike Forums
https://simplicityvintagecycles.com/2...aga-continues/
There's an online vendor called Loose Screws, which used to be bike oriented, but has shifted to firearms. They still have old bike stuff for sale though, including stuff that might work for you.
Shimano Dura Ace 4.5mm Downtube Shifter Screw w/D-ring - I used these to get cable stops on my shifter mounts, for use with bar end shifters. I removed the D-rings by putting the screws upside down in a vice and tapping them with a hammer to pop-off the D-rings. Having the screws is half the battle. These are them.
Shimano Z-401 Friction Downtube Shifter Set - can't vouch for these and the description incorrectly describes them as "Italian type", which they're not.
Shimano Dura Ace EX Downtube Friction Shifters Set - another bad description, but looks suspiciously like the correct shifters.
Here's a list of related threads:
Modification: Old style Shimano downtube shifter mounts to later style - Bike Forums
Shimano 600 shift lever woes on a Centurion - Bike Forums
Do I have "B" Style Shifter Bosses? - Page 2 - Bike Forums
Shimano 4.5mm Type-A Shifters / Downtube Braze-ons - What are my options? - Bike Forums
Help Me Out With Shifter Boss Covers on This Miiyata 912 - Bike Forums
cable stops for unusual downtube brazeons - Bike Forums
Downtube shifter boss compatibility - Bike Forums
https://simplicityvintagecycles.com/2...aga-continues/
There's an online vendor called Loose Screws, which used to be bike oriented, but has shifted to firearms. They still have old bike stuff for sale though, including stuff that might work for you.
Shimano Dura Ace 4.5mm Downtube Shifter Screw w/D-ring - I used these to get cable stops on my shifter mounts, for use with bar end shifters. I removed the D-rings by putting the screws upside down in a vice and tapping them with a hammer to pop-off the D-rings. Having the screws is half the battle. These are them.
Shimano Z-401 Friction Downtube Shifter Set - can't vouch for these and the description incorrectly describes them as "Italian type", which they're not.
Shimano Dura Ace EX Downtube Friction Shifters Set - another bad description, but looks suspiciously like the correct shifters.
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I didnt see the 6 speed index shifters with half moon adapters at loose screws
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Shimano Type A Shift Lever Bosses
"Google is your friend" an oft seen response on the old rec.bicycles.tech newsgroup....
Many times Google searches are easier to find information on BF than the Bike Forums search function. One suggestion though, please don't reply to old Zombie threads.
You responded to a stale 5 year old thread and 1. most of the links on old posts are long dead, 2. scrolling through reams of old posts to get to your new message discourages responses from many BF members who could help you...
It's usually better to start a fresh thread. You'll get more current info. Use the old threads for references.
I posted this response last week. While not complete, it gives you an idea of what parts you need:
https://www.bikeforums.net/22550126-post8.html
Most Shimano 5mm lever screws are stamped M5.
The 4.5mm screws are unmarked.
Spacers.
Best bet is scrounging through the junk boxes at bike shops that have been around for a long time or bike co-ops. You could try the "ISO and for trade thread" in the sticky threads part of the forum too.
Good luck
verktyg "50"
Many times Google searches are easier to find information on BF than the Bike Forums search function. One suggestion though, please don't reply to old Zombie threads.
You responded to a stale 5 year old thread and 1. most of the links on old posts are long dead, 2. scrolling through reams of old posts to get to your new message discourages responses from many BF members who could help you...
It's usually better to start a fresh thread. You'll get more current info. Use the old threads for references.
I posted this response last week. While not complete, it gives you an idea of what parts you need:
https://www.bikeforums.net/22550126-post8.html
Most Shimano 5mm lever screws are stamped M5.
The 4.5mm screws are unmarked.
Spacers.
Best bet is scrounging through the junk boxes at bike shops that have been around for a long time or bike co-ops. You could try the "ISO and for trade thread" in the sticky threads part of the forum too.
Good luck
verktyg "50"
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Don't believe everything you think! History is written by those who weren't there....
Chas. ;-)
Don't believe everything you think! History is written by those who weren't there....
Chas. ;-)
Last edited by verktyg; 07-07-22 at 11:51 AM.