Is it the model year?
Dear Lennard,
I have a 1999 Cannondale CAAD 5 equipped with Campy Record 9-speed.It has never shifted to my liking. I just read on Campagnolo's web sitethat there is a difference between 1999/2000 Record shifters and post-20009-speed record shifters and derailleurs. This has me totally confused.They say there is a way to tell the difference but I am not sure how todo it.What I do know is that last year out of total frustration I purchaseda new 9-speed shifter, cable set, 9-speed chain and new Record rear cassette(12-23). It now shifts better but still not reliable/smooth. Canyou help me with this annoying problem?
JimDear Jim,
I do not know why you are having problems shifting, but since therewere many CAAD 5s with that setup that shifted fine, I would have to suspecta bent rear derailleur hanger. Check it out with a shop that has the propertool to determine its alignment relative to the rear rim.As for the year of the shifter, if your Record Ergo Power 9-speed leverdoes not have a little oval hole on the inboard side of the lever bodyfor the button on an Ergo Brain computer, you have a 1999 version. Thelever hood cover, if original, also would not have the bump on the sidefor the Ergo Brain button unless it is post-1999. Another tip-off is thatalmost all Record levers of 2000 or later, whether 9- or 10-speed, arecarbon; 1999 levers are aluminum, and prior to 1999, they are aluminumwith the older, 8-speed body shape with the sharp point on the top.
LennardChain line?
Dear Lennard,
I have a BMC SLT01 with 10-speed Dura Ace shifters, rear derailleur,chain, Ultegra cassette, FSA Mega-Exo cranks and FSA front derailleur.I cannot get the bike to shift properly. I have read numerous articlesabout the shifting for the front chain rings, but my problem is with therear. If I get it to shift properly for the small chain ring, it shiftspoorly for the big chain ring and visa versa. All the components are brandnew. When it is on the stand and running smoothly for a particular gear,and I shift from the 50 to the 34 without changing the rear, the chainalignment is off and the derailleur needs adjusting.
KurtDear Kurt,
It sounds to me like your chain line is off. Strange, since with the MegaExo, that is not adjustable, unless perhaps you have a spacer on the driveside moving the right bearing outboard too far. Either that or the rearend of the frame is out of alignment, which would have the same effect.There are chain line tools you can try, or you can measure it; the methodfor doing that can be found in either "Zinnand the Art of Mountain Bike Maintenance" or "Zinnand the Art of Road Bike Maintenance."
LennardThere are dents and there are dents
Dear Lennard,
I have a Trek double-butted aluminum frame with just over 10,000 mileson it. While breaking it down and doing my annual cleanup and maintenance,I found a significant dent on the seat tube behind the chainrings justbelow the derailleur clamp.

I don't remember ever bumping the frame hard enough to cause the dent(particularly in such an odd spot) and there isn't any paint damaged either- could it could be the result of fatigue?

Is there anyway to validate the cause of the dent? And if it is fatigue,how long do I have before the frame is unridable? Will it ever be dangerousto ride?
KenDear Ken,
I could swear that I have answered this question at least once in thepast, but as I continue to get this question frequently, always with referenceto Trek, so I’ll answer it again. Many Trek models, including those made of carbon,have an oversized seat tube that would prevent the front derailleur frommoving inward far enough to shift to the inner chainring. So Trek intentionallyputs a dent there to give it the clearance it needs.
LennardSticky brake
Dear Lennard,
I've got a pair of Dia Compe BRS 200 brake calipers. The front seemsto be sticking (the right arm does not return to it's original positionand usually rubs against the rim) since I've replaced the fork (ReynoldsAero Pro). I've tried a few things that I could think of such astrying to tighten or loosen the bolts, but nothing seems to fix the glitch.Any ideas as to what it could be?
ChrisDear Chris,
As I recall, those are not easy to center. If memory serves, you simplyloosen the fixing nut behind your fork crown and rotate the entire brakewith a 13mm (maybe 14mm?) cone wrench on the flats of the nut behind thearms, and then retighten the fixing nut. The front nut will not help you - that sets the freedom of movement of the arms, and if you tighten it too much you seize up the arms. You may have to fiddle a few times to get it right. If you do not loosen the fixing nut, I think you can also inadvertently seize the arms when you turn the centering nut with the cone wrench.
Also, putting two or more knurled washers on the brake bolt betweenthe brake and the fork will help give you enough room to get the cone wrenchin there - otherwise it is very tough to do with the wheel on, which iswhat you have to center off of anyway.
LennardRegarding creaking pedals
Dear Lennard,
I have recently cured a long-standing pedal-crank tick. I have OctalinkUltegra cranks and Speedplay Ti pedals on a five-year-old aluminum frame.The whole bike is an acoustically tuned creak amplifier.

Having run through the usual suspects of chain rings and bottom bracket(which I did discover was shot, so replaced anyway) I still had my annoyingcreak. I eventually convinced myself that the problem arose from the contactbetween the crank arms and the pedal. Removing the pedal and lubing thearea has cured the issue completely. Note – the only reason I didn’t trythe recommended overhaul of the pedal bearings is that its such a hugepain – with Speedplays anyway – since from new they are daubed with bolt-strippingLoctite.

So, I guess I am fortunate that my laziness helped me stumble acrossthe true problem. However, my experience does make sense. Aluminum is prettysoft and pedals do have to be installed with a reasonable amount of torque.Such contact between dissimilar materials (steel and Ti, the common spindlematerials, both being much harder than aluminum) is a perfect recipe forcreaks.

My feeling is that the people out there repeatedly rebuilding theirpedal axles and finding that this has cured their creaks are doing so bycoincidence. After all, in order to replace pedal bearings, it is usuallynecessary to take them off. When I take anything off, I naturally gaveany threads a quick clean.
JerryDear Lennard,
In response to the noise coming from the bottom bracket pedal area, Ihad a similar noise occur on my bike, mostly during out-of-the-saddle efforts.After my husband checked the bottom bracket, pedals and headset with nochange, I came home to find my bike apart. He had finally found the sourceof the noise: a cracked chainstay. Be careful out there.
Erica

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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.