Road size versus 'cross size
Dear Lennard,
I'm in the process of purchasing a new cyclo-cross bike and a little confused about the sizing. I currently ride a Trek Madone (M) 56 with a top tube length of 56.2 and this fits me fine. I originally thought I would get a 56 XO1, but according to Trek's website, this is an XL but the top tube length is 55.5, a little less than my road bike, and the stand over height is 1.6 larger than the road bike. Should I be on a 54 (L) with a 54.0 top tube length?Any advice would be greatly appreciated.
InsungDear Insung,
There is no reason to go shorter on the top tube, but you do want a shorter seat tube to get more stand-over than your road bike, not less. To make that 54 work, you should use a 2cm longer stem. That would be the best of the options you are presenting.
Lennard

Doing the cols
Dear Lennard,
I am going into the French Alps this summer to watch the Tour. I will be attempting to ride part of Madeline, Galibier and Ventoux.My current Devinci road bike has Ultegra 9-speed . I would like to add some extra gears, triple chainrings etc. for my trip. What can you suggest , my most cost-effective option as I will be only riding half of my 8-day trip.
SteveDear Steve,
The most affordable approach would be to get a 105 crank, cogset, rear derailleur and chain.
Lennard

Vive la France
Dear Lennard,
The new Mavic Ellipse track wheels seem pretty nice, mostly. However, they use a French lockring (Vive la France and all, but what the hell else uses French standards these days?). Looking at the specs the diameter doesn't seem different enough between English and French to matter. The thread pitch is damn close too (25.4 tpi versus 24 tpi) which for such a narrow ring seems like it would work. Would this qualify as a "class B fit" or should French and only French be used?
DanAnswer from Mavic

We use the same lock ring we have always used on all of our track wheels. As for the fact that the reader comments "who uses French lock rings?" I'll simply direct you to the catalog of your own magazine as it seems the Mavic Comete is a wee bit prolific in its medal harvesting capabilities dating back to about the Barcelona Games. In fact at both the Athens games (80 percent of the track medals were won aboard Mavic) and the just-concluded track worlds in LA (where about 75 percent of the medals were collected on Mavic), there doesn't seem to be too many people who use these wondering about the lock ring. Someone might ask why people are using the Japanese lock ring thread pitch since it doesn't seem to work as well when comes to actually winning.Your customer and readers can get the Mavic lock ring from their Mavic retailer. Part #32397101. In stock.
Christopher Zigmont
Marketing Director
Mavic-adidas Cycling

A bit more on compact road cranks
Lennard:
I've got at Trek 5500 that I've retrofitted with a set of FSA's Compact Pro Carbon cranks. The Dura-Ace (10-speed version) front derailleur shifts pretty well on this setup, but sometimes, it throws the chain onto the bottom bracket during downshifts. The limit screws are adjusted correctly.I've been reading about Campagnolo's compact double specific designs for front changers. I have a couple of questions, though:

Do you think that they might help with the problem (It seems to be part of the sales pitch.)If using one of those Campy derailleurs with the rest of the Shimano drivetrain would work.

MarkDear Mark,
I have not yet tried that combination. Definitely the Campy derailleur design would be better in addressing this particular problem, which is not all that rare.Again, I would use an inner chain stop (Deda Dog Fang, Jump Stop, or Third Eye Chain Watcher).
Lennard

Triple front derailleur works great
Dear Lennard,
I replaced an Ultegra triple crankset with an FSA compact double, and the front derailleur shifting has been flawless. I replaced the long cage rear derailleur, but left the triple front derailleur alone. I was expecting some problems after reading some of your columns, but I think that must be with a double front derailleur. The new Campagnolo CT derailleur is built more like a triple, so maybe that's the key. A dog fang is probably a good idea on any bike, but I have experienced no problems when going to the small ring using that triple derailleur.
Bill

Finding stock 180mm compact cranks
Dear Lennard,
Just as an FYI for your column should the need arise: Stronglight does a 180 compact road crank with ISIS spline. www.zefal.com/stronglight
Angus

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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.