Dura Ace 7800 v. 7900 compatibility

[LegendRider]

Is the new Dura Ace 7900 backward compatible with 7800? For example, can I use 7900 shifters with an otherwise all 7800 set-up? Or, will I need some sort of upgrade kit?

[R3KC]

Here's Shimano's compatibility chart: http://www.dura-ace.com/downloads/interchangeability.pdf

I've heard on other forums that it is best to have shifters and the front der. at a minimum. With that set-up and the rest 7800....Should work fine.

Again not first hand experience, but will likely be the route I go first.

[SoCalSteve]

Here's Shimano's compatibility chart: http://www.dura-ace.com/downloads/interchangeability.pdf

I've heard on other forums that it is best to have shifters and the front der. at a minimum. With that set-up and the rest 7800....Should work fine.

Again not first hand experience, but will likely be the route I go first.

They say that the 7800 brakes will work with the 7900 shifters...But, not as well as the 7900 brakes...So I've been told.

[scrooge]

They say that the 7800 brakes will work with the 7900 shifters...But, not as well as the 7900 brakes...So I've been told.

Who are "they"? I wouldn't expect shimano to say otherwise...

[SoCalSteve]

Who are "they"? I wouldn't expect shimano to say otherwise...

The people who name the streets, of course.

Actually, there is a good explanation for both.

1.) Fr Der...Loses the trim feauture with the 7900 (I believe on the big ring). So, it needs a wider front der.

2.) Brakes..There was something about the way the 7900 brakes have a different type of action...The 7800 shifters will work, but not with the same modulation.

Take all this with a grain of salt as I have not installed anything 7900 (yet).

Steve

[BdaGhisallo]

I can second what's been said already.

If you go with the 7900 shifters, you'll need the 7900 fr derr at a minimum. Also, you'll likely want the 7900 calipers if you value good braking.

Otherwise, all else goes. The 7900 rings are said to work properly only with the 7900 chain, but I have no doubt that the 7800 chain will work just fine.

[scrooge]

The people who name the streets, of course.

Actually, there is a good explanation for both.

1.) Fr Der...Loses the trim feauture with the 7900 (I believe on the big ring). So, it needs a wider front der.

2.) Brakes..There was something about the way the 7900 brakes have a different type of action...The 7800 shifters will work, but not with the same modulation.

Take all this with a grain of salt as I have not installed anything 7900 (yet).

Steve

Makes sense...but don't let that stop you from buying my older DA shifters that will be in the classifieds one of these days (I'm waiting to go on vacation before I list them) :cool:

[SoCalSteve]

Makes sense...but don't let that stop you from buying my older DA shifters that will be in the classifieds one of these days (I'm waiting to go on vacation before I list them) :cool:

Make sure you go somewhere where there is no Internet access AND your PM box is full...

The only reason I would upgrade to 7900 is for the hidden cable aspect...and, at the price they are asking for them now...Its gonna be a long while before I buy a set (and fr der and brakes).

The 7800 stuff I own (and I own a whole bunch of it) works superbly, both the double stuff and triple stuff.

[gemship]

what is the best, ???el of the group? shifters?

if one bothers to swap out stuff why not go all the way?

[LegendRider]

The Performance Bike website says the 7900 chain will work with ANY Shimano 10 sp drivetrain. But, the chart seems to indicate otherwise. Which is correct?

Thanks in advance.

[pdxmech13]

7900 chain will work on both. No reason for it not to.

[LegendRider]

7900 chain will work on both. No reason for it not to.

Thanks. I knew it was the same width, but I thought the redesigned ramps, etc. might have an impact. And, Competitive Cyclist also says that Shimano claims it is not compatible.

[Jeff N.]

I finally, finally, finally sold Terraplane #3 and used that cash to upgrade my Holland Exogrid to complete DA7900, including new wheelset (7900 hubset laced to grey hard annodized OP's-outrageously nice!). Got the whole group off E-Bay for $1400.00. An appreciable upgrade over 7800? I'd say so, yes. I originally was going to go the cross-compatibility route but not being totally sure on compatibility, I just pulled the trigger on the whole group. Glad I did.
Believe me, it works as good as it looks. It'll get a workout up in Solvang next weekend. :banana: Jeff N.