The Adventures of Franz » Installing DuraAce 7900 Components

Awhile ago I decided that it was time to switch to a compact crankset so I bought and installed a DuraAce 7950, replacing the DuraAce 7800 chrankset that came with my bike. At the same time I put on a 7900 series cassette and started using the DuraAce 7900 chain.

Being the cheap guy I am I continued to use my DuraAce 7800 shifters, derailleurs and brakes. It was a workable combination but the shifting was just not the same as with my DuraAce 7800 double crank.

Lately I have had the urge to buy a new bike. There is not good reason since things were working fine enough, but the DuraAce 7800 shifts have the older design of the shift cables routed outside and everyone has changed to internal routing. It is kind of like driving an old car. Sometimes you just want to drive a new one.

Although my components were now 4 years old, much of the bike was much newer, with the frame and crankset replaced 2 years ago and the wheels replaced within the past year. So instead of going done the route of buying a new bike, I decided to replace the components that were still there from the original bike, which meant new shifters, brakes, and front and rear derailleur. I had considered to go with SRAM Red, which is very popular now, but I have a couple of road bikes plus the tandem that have Shimano components so I wanted to keep everything Shimano and with a shifting method I was use to.

All of the components were on sale individually at Performance.com so I placed the order for a total cost of $980 (less 10% in the points I get back for future purchases). This included the ST-7900 Dual Control Levers, BR-7900 Dual -Pivot Caliper Brakes, FD-7900-B Front Derailleur, and RD-7900-SS, Rear Derailleur. This was much cheaper than the $7,500 I would need to spend on a new bike with a top of the line frame, like I have, and DuraAce 7900 components.

Installing the brakes and rear derailleur was fairly easy because they were very much like what I have used in the past.

When it came to putting on the shifters that was a whole different store. Even attaching them to the handlebar was puzzling and the instruction sheet that came with them was a bit hard to follow. After getting them installed, I then had to route the brake and derailleur cables, which was tricky because it was so different than what I had done in the past.

Adjusting the rear derailleur was straightforward since it was similar to what I had done in the past. The front derailleur was not so simple and the method of adjusting the cable tension was completely different. I had to keep fiddling with it, even starting over a couple times. The setup is suppose to allow you to use any gear combination without the need for trim in the shifters, but you have to do it just right to achieve that. It is complicated by Shimano stating there is no trim, but the shifters do allow for two clicks going into the big chain ring. One cycling friend had put in considerable slack in his cable so he used both clicks to get into the big chainring. That just didn’t make sense to me because Shimano would not design something that required that type of effort. I could setup things so it would move quickly into the big chainring, but the amount of tension caused the chain to rub when I was in the small chainring and largest cassette because the cable pulled the derailleur off the stop against the chain. I finally solved that by a slight rotation of the derailleur. If you have it off alignment, especially with the tail-end pointed outward even slightly, the very narrow range you have to work with with no trim is not sufficient.

It was only after I finished the job, reading and re-reading the instruction sheets, that I found this great video. If I had watched this first, I would have saved myself some time. Everything in the video is in the Shimano supplied instruction sheets but the video makes it easier to understand.

Shimano Dura Ace 7900 Installation Guide from ProBikeKit on Vimeo.

If you happen to be installing Ultegra 6700 components, this video will show you have. If you are installing a triple crankset, this video will also show you the differences in the installation between a triple and double (or compact) crankset.