Old 06-10-14 | 10:19 AM
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volosong
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crossing derailleur cables under the downtube - it's "wrong", correct?

Boy, I'm so bummed. I've been taking my sweet time building up a new Pinarello KOBH frame with Ultegra 6800, (since marketed as the Dogma-K). Got most of it put together and took it to my LBS, and had a specific "kid" who I've worked with in the past do the final cable adjustments and have him cut down the steerer tube and double check the torque on all the bolts. Didn't expect it for about a half a week, but he called the next day to have me come and pick it up. Great! Last night, I started wrapping the bars, the final step before the inaugural ride, (I like my tape "just so").

First thing I did was take off his black electrical tape that he applied to hold the cables. That stuff is just messy! Why did he take my white tape off anyway? Cleaned the gunk off and re-taped the cables in extra places so that they would run exactly where I wanted them to run, and I used white tape. A lot cleaner. Finished one side with cloth bar tape, (I'm "traditional"), and was ready to start on the other side when I noticed something that "wasn't quite right".

Hmmm? Huh! Flipped the frame over on it's "back" and I couldn't believe it! He had crossed the derailleur cables under the downtube! Pinarello carbon frames that do not have internal cabling have their adjustment and cable housing stops on either side of the very top part of the downtube. The bare cable runs down either side of the downtube to the plastic cable guide under the bottom bracket. The front derailleur cable goes up through the frame behind the seat tube to the FD and the RD cable continues back to the RD under the chain stay.

The problem with crossing the cables is that they rub against each other and will prematurely wear and fray. And, probably worse is that they rub against the frame and will wear a groove in the carbon! I can sort of understand why he crossed them because the cable make a more graceful bend if the cable coming from the left shifter looped around the head tube and ran down the right side of the seat tube from there and the cable from the right shifter loop around the head tube to the left. But, that's not the way my other two Pinarellos are "wired".

I just hope there is enough cable to re-run them correctly without having to purchase new cables.

The search for a new mechanic starts today. Looks like a highly-regarded Pinarello shop is located in Irvine, about a three hour drive from where I live.
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