trailangel

OMG.... don't take your hand off the bars.

3alarmer 

...there's an internet page that describes the whole history of this in depth and at some length here.

Dura Ace was not made compatible with the other stuff until 1997. That's a long time to wait, if you were genuinely interested in making your Dura Ace shifters and derailleurs work with everything else.

I was reading the advertising of the time, and my impression was that they didn't change it because they wanted it different. This made it "better" in some strange way. I know I thought it "better" at the time.

Dave Mayer

About 10 years ago, a mint Guibulato (sp?) road bike with first generation Dura-Ace brifters dropped into my lap. It was too big for me, so I sold it to a pal. He loved the bike, but wanted lower gearing; as we know, the tiny Dura-Ace rear derailleurs of th time could barely handle a 26 tooth cog.

So I swapped out the DA rear derailleur for a Suntour XC Pro (Accushift), and a 32-tooth cog on the cassette. Worked perfectly. Which implies that old Dura-Ace with a derailleur actuation ratio of about 1.8, is the same as Accushift.

Regarding Shimano's Centeron floating upper jockey wheel... this feature does nothing to 'correct' mismatched shifters and derailleurs.

KCT1986

Dave,

Thanks for sharing your experience about using an Accushift RD with a DA brifter. Guess that the Accushift ratios are the same as 740x DA or reasonably close.

Sometime in the future, I'll probably give it a try. Bike isn't set up right now. Had it with a 9 sp DA brifter & RD-7400, shifting 8 cogs. When I put it back together, I'll try to swap in the Sprint RD and see if it also shifts 8 speed.

thunderfoot

Dave, I think I’m going to give the Microshift’s a shot. What are the pros/ cons of running it with my current 6 speed freewheel (which was my original plan) versus swapping it out with a 7 speed freewheel?

KCT1986

ofIf I may chime in.

If you get a 7 sp Microshift shifter and use it with the RD-7400, it will shift correctly for 6 speed spacing. To shift 7 sp spacing, you will need a non-7400 series RD (most road RD from Shimano up to 10 sp).

Using a 7 sp shifter with the RD-7400 means that you keep most of the bike untouched but gets you brifters.

thunderfoot

Chime in, by all means.

All of this is obviously outside of my area of bike component-understanding so forgive me if I sound clueless here... so what happens with the 7th click in the new shifter if I’m only running 6 speeds? Do I need to do something to stop the chain from shifting to a cog that isn’t there or is there just a blank click?

KCT1986

You can set up the shifter/RD as normal, set the shifter to high position (smallest cog) and attached cable. This will put the extra click on the low end. Just need to adjust the low gear (big cog) adjuster screw to limit the travel of the RD towards the spokes. Trying to shift further you'll experience resistance as the RD won't move further. I guess trying to force it further will stretch the cable a little, but unless you get too heavy-handed shouldn't be a problem.

masi61

If you’re wanting to stick with your 6 speed parts, but you want “brifters”, I would suggest getting a set of Gevenalle “Audax” shifter pod sets from Gevenalle. These are basically some really nice Tektro aero brake levers with a cleverly designed braze-on at the top of the lever. Your Dura Ace 7400 6-speed levers could be moved to these Gevenalle pods quite easily and everything will work correctly because you are using the correct shifters. These were out of stock for like a year but I believe they are now back in stock. They aren’t cheap - last I checked they were like 159.99 or something like that, but for what they are they are fantastic. It is necessary to locate flat shifter backing plates since the ones on your downtube braze-one are most likely the concave type. You’ll still re-use the concave backing plates where they are in order to make a clean installation of the down-tube adjuster barrels/stops you will be using.

You get to shift from your aero levers, very handy! For commuting or riding on roads with a lot of cars, this configuration can help you keep your eyes on the road. I guess cyclocross racers are the main market for these because they can survive crashes. You can’t say that about regular “brifters”.

If you do elect to go with the Gevenalle Audax pods, you will need to use your down tube braze on bosses for derailleur stops, no big deal really. You will also then need to run lengths of derailleur housing (compressionless) from the sides of the tops of the aero levers down to the stops. I like the look personally, but I also like the look of classic Shimano brifters that shoot the derailleur housing out the side of the shifter.

Shifting technique with these takes a (very short) learning curve. Since the shifters point downward, the shifting will seem upside down at first. It was really no big deal for me.

I converted a Dura Ace 7400 7-speed Uniglide rear cassette hub to a 7x3 road triple configuration and it works very well.

Your existing 7400 front shift lever is friction only and can run double or triple cranks. The fact that you only have 6 rear cogs does not have to be a limiting factor since you can run a triple crank if you want.

djb

years ago I thought of doing the same thing with my old 1990 touring dt bike. At the time, there were no 7 speed brifters, affordable ones that I knew of, around, so without knowing the specifics personally of the microshift 7 sp brifters with your original rear derailleur, this sounds like a reasonable option.
Heck, even changing the rd to one that will work is not a big deal no? This way you will have 7 speeds (assuming the body of the wheel will take a 7 speed freewheel, and also there are not a lot of options in 7 freewheels, the ones I see are nearly always 11-28 (have replaced old ones with new ones of this size in the last few years on old bikes we have)

but as someone elso who has
1-ridden decades with dt shifters (ok, but hey, for real world riding, brifters are just plain nice to use)
2-ridden a lot with brifters--just plain fun and nice to ride
3-owns and have ridden a lot with Gevenalle shifters---pretty neat shifters, but as stated, are not cheap, but then if you can get microshift ones to work, you will have indexed shifting, which is just plain nice compared to friction.

in the end, to my mind, changing technical stuff wont change the emotional aspect and overall look of the bike, it will still be that bike your dad setup for you, but it will be more fun to ride, brifters, indexed, 7 speed etc....

and yes, I guess a used rear wheel with a 7 speed already on it could be found at a good price, so that, shifters, redo the cables etc yourself.....wouldnt be too expensive.

as for my old bike, I redid all the cables, housings, got a new headset, new bartape and ended up just leaving it as is with dt, really because of the cost, and I keep for emotional reasons (first longer bike tours on it, first time in France etc) and for the last bunch of years, I use it on my trainer during the winter instead of using a newer bike, so I sort of still ride it, but am not dt shifting all that much and not in traffic commuting, which I did for years.

I guess you really need to look at some dollar figures and also decide how you want it, and only you know that.

djb

ps, very pretty bike btw

masi61

The “Audax” version of these comes without the friction shift levers. It simply comes with the braze-on posts that let you use your own shifters (with the flat backing plates). Since you want to keep your bike original, that would be the one to get since Dura Ace 7400 s.i.s. rear indexing is going to work best with your specific 7400 rear derailleur and indexed shift levers. You are running your 6 speed freewheel in indexed mode, yes?

thunderfoot

I totally agree.... I’m good with switching some stuff up, I just didn’t want to get to a point where I was having to break up the matching DA group set tooooo much. I’m itching to get it figured out and parts on order... probably gonna pull the trigger on some stuff this weekend. Thanks for the input!
These seem waaaay cooler to me now that you’ve explained the Audax version... I was under the impression they were all friction style... pretty sweet that I can use my SIS shifters on these. Yes, I run them in indexing mode.

My dad told me that when he purchased them back in the early 80’s, they had JUST come out.... He was at a LBS and the owner had just returned from a bike industry show in NYC where he picked them up from the Shimano booth. Since indexing shifters were brand new tech and so unknown at the time, the owner only bought one set just to gauge interest. He hadn’t even put them on display in the shop yet. The next time my dad was there, he and the owner were chatting about the show and he showed the shifters to my dad... he bought them immediately , lol.

masi61

That’s a pretty cool story. Your dad really appreciated what a huge technical achievement something like that was. I have one of those 7400 6/7 speed rear derailleurs and they are very classy. Same with the 6 speed S.I.S. shifters - these were clear anodized silver which look more high quality than the later gray anodized ones. My 1st indexed shifting bike was a used “Saint Tropez” that I bought off my bother in law around 1990. It had the (new to me at the time) indexed 6-speed Shimano 105 group on it. The down tube 6 speed shifters weren’t indexing properly with the rear 105 derailleur so I ran it in friction mode for quite a few years. I put several times over 5,000-7,000 miles increments on that bike in different build iterations. The hubs were 6-speed 105 Uniglide as well. I thought the Uniglide cassettes were the coolest thing ever, the way you could use a chain whip to remove the outer locking cog and then easily clean each individual cog with simple green, paper towels and a toothbrush.

Every time I decided to rotate the knob on the shift lever from friction to “S.I.S” the rear shifting would be off in one or more rear gears. I tweaked and turned the adjuster barrel and loosened the cable cinch bolt to remove cable slop. Shifting got faster, and some cogs would now shift fine while others that worked fine before would be noisy. I had never even heard of the term derailleur hanger alignment. Until I set out to get this nifty 6 speed 105 setup to index correctly.

The deeper I dug into mechanic forums, the more I kept hearing about the importance of aligning the derailleur hanger coplanar (I believe is the term) with the cassette cogs and the derailleur pulleys. Eyeballing the cage from the rear of the bike, I thought I could see something askew. But I really didn’t know. I decided to buy the Park Tools Derailleur Alignment gauge (DAG-1 if I recall correctly). I followed the enclosed instruction sheet and started taking measurements with the 1/4” rod a different spots around the rim. I was starting to get it. The derailleur hanger was bent. Why was I so clueless about this issue but still managing to rack up thousands and thousands of training miles all in friction mode? So I used the DAG-1 to carefully goose that derailleur hanger up a little, then forward a little, rechecking each time with the little 1/4” rod on my rim sidewalls.

Sorry for for the long winded story... guess I had to give the back story in order to understand the joy I experienced when I eventually learned how to tune the indexing spot-on. Yes, I was a bit of a slow learner since I had to do the work in order to fully understand it. But getting it set-up correctly, then being able to benefit from the ease that the Shimano engineers at the time knew about was a bit of a game changer. So, yes- I think the story of your dad getting one of the early Dura Ace 6 speed drivetrains is very cool!

djb

Oh, also about the gevenalle units.
Mine is a 9 speed one with cable pull for mountain bike mechanical disc brakes, BB7, and as with all of their various versions, 9,10,11, there is a little rotating part that switches from index to friction.

But honestly, indexing just works. Like the last guy described, if everything is in order, it's flawless. My 1990 or 91 dt 7 speed tourer has shifted perfectly other than a handful of times when a slight barrel adjuster turn was needed a few times, other than that perfect shifts every time, up until today when I ride it on my trainer.

I also find the gevenalle units to be actual pleasant to use. Part of riding is, for me, a physical enjoyment of how stuff feels, shifting etc, and I like how they feel.
Handy like brifters, but with a physicallity of moving your fingers in different positions to shift that I like.
I bought them to set up a tough touring bike for some Latin America trip, and have spent months on that bike, a third to a half of Mexico, through central America, across France, and millions of shifts, and I like it still and enjoyed the physical shifting.

So that's my positive report on them, AND I think they look damn cool and different. A cool mix of old and new.
The company used to be called Retroshift, but I figure they realized the retro wasn't good for younger folks, so changed the name.

BobFishell

6,7, and 8-speed systems have the same cog spacing, so you can use brifters made for 8-speed drivetrains. The lowest position on the rear shifter corresponds to your lowest gear. This leaves you with two extra positions at the top end, but all that will do is put some slack in your cable. I used a setup like this with a 7-speed freewheel on one of my bikes before I adapted an 8-speed freehub axle to work with 126mm dropouts.

The trick is finding 8-speed brifters. I think Shimano Sora is still 8-speed, although I'd try to find some NOS 105 or Ultegra components.

djb

Sora was 8 for ages, the ones with thumb shifters, a la Campy, but in their last year they went to 9 speed, but still thumb shifter, and then they did a whole "trickle down" down and changed sora to be very similar to the old 9 speed Tiagra brifters, with the paddles instead of the thumb thing.

the thumb soras work, but I found them kinda stiffish, certainly compared to my 9 spd tiagras, and when they went sora paddles, they felt just like my 9sp tiagra (bought some paddle Soras to replace a broken 9 sp thumb sora on my wifes bike about 3 years ago)

isnt the issue the cable pull? Using 8 spd brifters on 6 spd.
I admit I dont have the knowledge about this

BobFishell

The cable pull isn't a problem, since you are only using the first 6 of 8 clickstops. You tension the cable on the little ring and the first cog. If you accidentally shift into the 7th or 8th stop, you just get a little slack in the derailleur cable, not enough to cause problems. I used an 8-speed STI brifter on a 7-speed freewheel for a couple of years and I didn't have any problems with it.

KCT1986

Couple of comments on prior posts:

"6,7, and 8-speed systems have the same cog spacing" - This is not always the case. Although Shimano/Sram 7 & 8 are really close, 5.0 & 4.8; 6 speed can vary between companies and intended use. 6 speed freewheels could be somewhere between 5.0 - 5.5 depending on the frame spacing expected (126-130mm).



"isnt the issue the cable pull? Using 8 spd brifters on 6 spd." - Yes, this is usually the problem. The 8 sp shifters doesn't pull the correct amount of cable to reliably shift most 6 sp cogset. If you have a cogset with 5mm spacing and use a non-740x series (not the case here), it could work.

See the PDF in post #10.