OldsCOOL

Maybe you've already tried this (if so, just ignore it)....did you try a 1/4" drive socket of that size? Or is that the only size drive to fit? They are thinner walled, of course.

Just a thought.

bikemig 

This thread is old but it has a lot of useful information for installing suntour barcons,

Mr. Juicy Juice

anyone know the best adaptor to use to convert a suntour barcon set up to a downtube set up? Is it even worth it to keep the shifters or should I just buy new ones?

OTS 

@Mr. Juicy Juice

Welcome to the Forums
I think I have seen your question in three posts so far this morning.
One in the For Sale threads and 2 here.
The best way to get an answer to your question is to start a new post.

My answer to your question is Suntour Barcons are popular and sought after by some here on C & V, I personally would NOT bother with a modification.
Quicker, easier to just get/buy some Suntour downtube shifters.
You can most probably easily sell your Barcons here to fund your purchase X3

JohnDThompson 

Riverndell makes an adapter to convert downtube levers to handlebar end mounting, but I suspect it would be an exercise in futility to try to go the other way.

Sell the bar-cons and buy a set of downtube levers. If your frame doesn't have lever mount bosses brazed onto the down tube, the clamp-on SunTour "Power Shifters" are a good option.

clubman 

Suntour made a couple of different versions of downtube shifters with the same ratcheting mechanism as barcons. They're called power shifters and they are plentiful and reasonably priced. Sometimes they came with smaller clamps for stem mounting.

Mr. Juicy Juice

@OTS Thanks for the help!

Also trying to get my 10 posts for pics privilege!

thook

with respect to forum rules/moderators......forgive if this type of posting is inappropriate. please, do let me know if it is

@Mr. Juicy Juice

if you'd like to trade, i have several sets of downtube shifters. PM sent

MnHPVA Guy

At first found that surprising, as I have been using them since '77, have them on a dozen bikes, and have never lost the nut. But then I remembered a tool I made 40 years ago that allows me to properly tighten them. I started with a very large screwdriver, so I could get a good grip. I shortened the shaft enough to fit it between the right shifter and the bike and cut a 4mm wide slot in the end. Overall length 7"


If your nut is gone, 3D printing and a gent on the iBoB list have come to the rescue. It is described in this thread. Buying details here. $7.50 plus S&H gets you a pair. I bought a pair, "just in case". I haven't tried them, but they are made from some very tough plastic. There is a bit of the plastic connecting the 2 pieces and it was very tough to cut.

thook

how'd you shorten the shaft? remove it from the handle and cut, or just cut the shaft down and grind to a flat?

MnHPVA Guy

Removed it and cut.

thook

and, how'd you remove it? i've got a donor drive i want to do this with

MnHPVA Guy

It's been 40 years. I can't remember what I had for breakfast. I assume a bench vice and a big hammer were involved, but I don't remember what else.