PDA

View Full Version : first compact crank...


Dave
03-17-2008, 07:21 PM
I received the 50/34 Chorus UT compact crank that I ordered recently, along with a 2008 Chorus CT/STD front derailleur and an 11-25 cassette. It will be replacing a 53/39/28 triple with an 12-25 (yes, I'm losing two of my lowest gear ratios). If I ever need more climbing gears, I've got a 13-29 that I can slap on, but a 50/13 isn't much top gear.

Installing the UT crank was real easy. There have been a lot of discussions on facing the BB. I took my own advice and screwed the cups in until they contacted a .010 inch feeler gage, then used feelers in the .008-.012 range to search for high or low spots. Both of the faces on my frame matched the cup faces within .002 inch, which should be good enough. The cups came with some yellow thread locker material on the threads, so rather than use Loctite 222, I greased the threads and torqued the cups as specified, using a Park BBT-19 cup tool. The rest of the installation only took a few minutes and I had a new crank that spun easily.

I wanted to try my old triple FD just to see how it shifted the compact crank. I had to lower the FD the expected 6mm, since I now had a 50T big ring instead of a 53. It took very little time to get the triple FD working nicely. About the only difference in the operation of the triple FD is slightly more effort, since no triple FD has the longer lever arm of the new QS FDs.

I then installed the new Chorus CT/STD front derailleur and got it working quickly too. As expected, it takes 4 clicks instead of 3 to cover the full range of travel with the QS FD.

Also, as expected, there's a little rub of the chain on the big ring in the 34/12 or 34/11. I suppose you could use 34/12 for awhile if you new you'd be shifting out of it quickly.

I'm still waiting on new Easton EC90 SLX3 handlebars to try before completing the rebuild. If they feel decent, those will be this year's experiment with non-anatomic bars.

pdxmech13
03-17-2008, 10:26 PM
yah that compact is a nice one.
i stumbled a little with getting that stupid clip on.
a 50-13 is good enough for getting around too i think.
:beer:

Satellite
03-18-2008, 12:55 AM
I'm still waiting on new Easton EC90 SLX3 handlebars to try before completing the rebuild. If they feel decent, those will be this year's experiment with non-anatomic bars.

Dave,

I didn't realize I was buying your handle bars before you bought new ones. I could have waited to pick them up.

Let me know how you like the SLX3's compared to the FSA's. The 40's feel good while riding flat roads but 42's would be better for climbing. I ride in the drops when climbing because they are swept and a little wider.

Thanks again for the bars I hope you get your ride dialed in.

Satellite

Dave
03-18-2008, 09:40 AM
Dave,

I didn't realize I was buying your handle bars before you bought new ones. I could have waited to pick them up.

Let me know how you like the SLX3's compared to the FSA's. The 40's feel good while riding flat roads but 42's would be better for climbing. I ride in the drops when climbing because they are swept and a little wider.

Thanks again for the bars I hope you get your ride dialed in.

Satellite

I didn't need those bars. I had them off for weeks before you got them. I've still got my previous EC-90 Equipe anatomics, if needed. I'm riding my winter bike until the roads get cleaner. Hopefully I'll get the new SLX3 bars this week, but I may not keep them. I've carefully mounted other bars, just to setup the ergo levers, check the reach and the feel the hooks. If I don't like them, I return them before riding. If these look promising they'll go on for good. If not, it's back to the old ones for this season.

I am anxious to try the compact. For some reason I'm able to spin a bigger gear than I have for 5 years. I've been up the steepest section of my regular ride and managed to do it seated with a 39/29, even with 7 pounds of winter fat on me.