shnibop 

i currently have dura ace 7400 group downtube shifters and want to convert to brake/shifters, i checked velobase and whatnot and it seems that as the 7400 group was refined there was a brifter setup introduced.

my current setup:

SL-7401 downtube shifters
FC-7400 crankset
FD-7400 front derailleur
RD-7401 rear derailleur
MF-7400 7spd freewheel

aside from cable stops (to replace current dt shifters), what else would i need if i'm trying to stick to DA components from that era, and preferably the same group. the made the ST-7400, but is that only for 8spd? will i need to convert to 8spd also?

thanks in advance

junkfoodjunkie

To get it to work "perfectly" you will nee to have an 8 speed hub and cassette. Your RD should still work but the spacing between 7 and 8 speed is different. It might work with just switching to STI but the setup might take awhile.
Here is a link to Sheldon Brown's page on DA compatibility https://www.sheldonbrown.com/dura-ace.html

Jake

RobbieTunes

What he said. He and I have both been there. Actually, using the same parts.

One option is to simply get 7400 STI shifters, and see if they work with the 7-sp 7400 freewheel.
If they do, you've got one "dead" shift, but you're done with just shifters and cable stops.
Once the initial adjustment(s) are done, you may have a great situation.
You'll have to play with it a bit, no doubt. I think the 2nd cog is generally the one it wants to mess up on.

If they don't work with 7-sp, you then have two more options:
a) Convert that 7400 freewheel setup to a freehub and cassette, use an 8-sp cassette. Conversion hub + longer axle + redish.
b) Get an 8-sp wheelset with a freehub and cassette.

I've done both with no problems. I just always kept my 7400 RD paired with my 7400 STI shifters.

Sometimes, 8-sp 7400 STI's are a little cheaper, because they really only play nicest with 7400 RD's. Sometimes, because folks are in your situation, they drive the price up because they have to have those shifters.

Others will weigh in, so don't consider me the expert.

gomango

To the op:

Robbie and Jake know what they are talking about with DA 7400.

I love this gruppo as well, and still use it on two bikes, with an extra gruppo hiding from my grease monkey boys.

I am the guy that drives the prices up on ebay I am afraid.

shnibop 

to junkfoodjunkie and robbietunes- thanks for all the info and the link to sheldons, very helpful. so it seems to get things to work as intended and be fully functional i would need:

cable stops
shifters ST-7400
an 8spd cassette and hub setup

my current crankset, front derailleur, and rear derailleur should all be reusable after the switch

any issues with using and HYPERglide vs UNIglide hub/cassette?

the only st-7400 i can find are on ebay and $170+, that sound right?

and is rear spacing going to be an issue? 6/7spd is 126mm and 8spd is 130mm right?

to gomango- lay off ebay for bit so i can get what i need cheaper, lol

miamijim

Any 8-speed cassette/hub will work regardless of it being UniGlide or HyperGlide. RSX, RX100, 105SC, 600 Ultegra, Dura Ace, Deore, Alivio, Exage...it doesnt matter. All 8speed hubs will be 130mm spacing.

Allan Pollock

ok for spacing, but not all 8 speed cassettes will work with that set up. with the 7400 series, you need a matched pair of dura ace cassette and shifters. That Sheldon Brown page has all the required info.

Allan

YoKev

I personally use an 8-speed Sora cassette with my 7400 rear derailleur and 7400 STI's. So yeah, that's my (very good) experience.

EddyR

I have a 1987 Cannondale SR-2000 Dura-Ace. It is a 7 speed like yours. It is hard to find a 8 speed Dura-Ace cassette that will fit as the 7 speed Dura-Ace is not the same as other Shimano hubs. I got a set of 8 speed STI-500 shifters and they work fine. No problems at all. They are a nice built shifter brake lever, much better than the low end Shimano STI shifters. They seem better built and smoother than my 105 STI shifters. They tend to run well over $200 but if you keep a good look out sometimes they show up for $150. They seem to me to be the same a Ultegra shifters.
Ed

miamijim

NO. That is incorrect. 740X shifters need to be paired with a 740X derailleur. The cassette and hub have nothing to do with it.

miamijim

I believe your reffering to Shimanos Dura Ace UniGlide hub and you are correct, the first position cog (high gear) is a smaller diameter than other Shimano UniGlide hubs.

Allan Pollock

thanks, my mistake.
Allan

Fred Smedley

Interesting trivia. My DA 8 speed 7402 downtube shifters/derailleur index perfectly with 8 speed Sachs freewheels.

miamijim

Thats is correct.

roccobike

Unless you have to have DA, why not go with 7 speed RSX STIs? They are paddle shifters just like DA, not like SORA. I have them and I like them.

Fivethumbs

A note regarding the 126mm vs. 130mm rear hub spacing: A lot of people will say to permanently spread the rear dropouts to 130mm (cold setting). I did this on my bike. Others will say you don't need to, that you can just pull out on the dropouts while forcing the 130mm spaced hub into the dropouts. Either way is fine. If anyone can remember back then (around '89) when Shimano came out with the 8 speed/130mm spaced hub, there were no bike manufacturers making frames with 130mm rear dropouts. Shimano actually designed the rear hub to be forced into the 126mm spacing with no cold setting. After all each side is only moving 2mm. The only advantage to cold setting the rear end is to make rear wheel changes a little faster/easier. Some people have posted that after having the 130mm hub in the 126mm rear end for an extended length of time actually caused it to stay that way on its own.

champion city

This explains my troubles with my 8 speed DA bar end shifters. the shifters claim to be compatible with 7400 and 7800 rear derailleurs, does anyone know how much cable they pull vs. "standard" shimano cable pull numbers?