Crank options
Dear Lennard,
I am going to Corsica in September. My bike has a standard Dura-Ace10-speed drivetrain with a double chainring. I would like to put on a compactcrankset for the trip, then reinstall the original after I return. My preferencewould be to not install a new bottom bracket. I could go to a triple. Doesany compact crank fit the Dura-Ace outside bearing bottom bracket? CanI run a triple Dura-Ace or Ultegra as a double without changing out theread end? I would rather not have to get a new crank and bottom bracket(like an FSA) just for one trip.Many thanks.
BobDear Bob,
The Ultegra 10-speed triple will fit in those bearings.
LennardChoosing chain length
Dear Lennard,
Thanks for all the comments on moving to compact cranks. I did it lastmonth and the system works well. However, the chain makes a new sound (likeit is bouncing) when I shift between the 50 and 34 chain rings. I have"Zinnand the Art of Road Bike Maintenance,"and did not see a table specificallydescribing how to determine the proper number of links in the chain forthis new set up. I have a 54 CM Trek Carbon Frame and run a 9-speed Dura-Acerear derailleur and 12-27 cassette. How many links of the chain shouldthere be with this set up instead of the one that had the old 53x39 combination?
TerryDear Terry,
The chain length determination is the same as described in the bookfor any other double. Wrap the chain around the big ring and the smallcog and through the derailleurs. The rear derailleur jockey wheels shouldbe vertically one above the other when you have the correct number of linksin the chain.
LennardBig teeth?
Dear Lennard,
A friend of mine has been riding with an FSA compact crankset for sometime now. I recently asked him if he had experienced any of the shiftingproblems I had heard about. He said the problems were primarily with the50x34 configuration, and he has a 50x36, which works flawlessly (he claims).When I have looked online at compact cranksets, I see them offered onlyin the 50x34 combination.Is a 50x36 readily available and does my friend’s assessment of theshifting problems seem logical to you?
CharlesDear Charles,
A 50x36 and a 48x34 are both available and have the same jump in gearteeth (14 teeth) as a 53x39, and we have found shifting problems to beless with those combinations.John Bradley of Orbea, which sells lots of bikes with compact FSA cranksand Shimano component groups, told me that they and FSA discovered thatthe compact chainrings do indeed have trouble with Shimano 10-speed chainsbecause the FSA teeth are a little thicker than those on a Shimano 10-speedchainring. This means that the chain does not move right away when shiftingdown but instead waits until the pressure from the front derailleur becomeshigh enough to overcome the extra friction keeping the chain from droppingoff the big ring to the small. Many times, it then slams the chain so hardthat it throws it over the inner ring.This is where an inner stop like a Jump Stop, Dog Fang or Third Eyehelps, although it won’t fit on all bikes. The Trek OCLV carbon is oneon which they do not fit. Over time, the chainring teeth wear, and thisproblem goes away. FSA is now working on chainrings with thinner teethfor these chains.Another reader told me that he tried the new Campagnolo compact frontderailleur with a Shimano chain, cogs, rear derailleur, and STI levers,coupled with an FSA compact double crank. He said that the chain wouldnot climb to the big ring, rather that the derailleur tended to push thechain straight against the side of the chainring and pin it there, ratherthat making it climb up. He switched to an IRD compact front derailleur,and the problem went away. Yet another reader reported using the CampyCT front derailleur with an FSA crank along with Campy 10-speed Ergopowerlevers and drivetrain. He says it works flawlessly. Our local Campy guru,Peter Chisholm at Vecchio’sbike shop also says that the Campy CT front derailleur won’t work withSTI, but that a Shimano triple front derailleur works acceptably in a pinch.I still have yet to try the Campy system myself as a unit, much less mixingand matching components. But everyone I know with the complete Campy systemsays it works well.
LennardFollow-up on the 105 Triple
I received a great deal of feedback about my suggestion to the riderplanning to ride the Madeleine, Galibier and Ventoux. I suggested a 105triple setup.First off, yes, an Ultegra 9-speed double left STI shifter willshift a triple crank, but you lose the feather adjustment at each end ofthe stroke.Several of you pointed out that I failed to offer a cheaper suggestion- one which we have discussed here in the past - namely putting ona mountain bike cogset, say an 11-34, along with a triple rear derailleur.This definitely works, and I have set bikes up this way in the past. Itthen gives you a 39x34 low gear with a double.Another idea many of you offered is to use a compact crank with 34-50chainrings with his existing cogset and derailleurs. About $200 for anFSA compact crank and bottom bracket. Forgetting the least-cost issue forthe moment, if you were to use a compact crank with the MTB cogset andtriple rear derailleur, your lowest gear would be 34x34, or one-to-one,which is about as good as you'll ever get with a triple.
LennardGrease and carbon
Dear Lennard,
I have a 2004 Bianchi EV3. It features a semi integrated Cane CreekZS headset. Two aluminum alloy cups are pressed into the headtube, intowhich the TH cartridge bearings sit.
I have been advised to grease the cups before placing the cartridgebearings into them. Because of the close proximity of the carbon steererto the bearings, does it matter if grease migrates across and comes intocontact with the steerer as it passes through the bearings? Should I insulatethe steerer at those points with a few turns of electrical tape? ShouldI paint it?
RonDear Ron,
Grease will not harm your carbon steerer, so there is no need for anyof these measures.
Lennard

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Technical writer Lennard Zinn is a frame builder (www.zinncycles.com), a former U.S. national team rider and author of several books on bikes and bike maintenance including the pair of successful maintenance guides " Zinn & the Art of Mountain Bike Maintenance" and "Zinn & the Art of Road Bike Maintenance."Zinn's regular column is devoted to addressing readers' technical questions about bikes, their care and feeding and how we as riders can use them as comfortably and efficiently as possible. Readers can send brief technical questions directly to Zinn. Zinn’s column appears here each Tuesday.