Originally Posted by
Metzinger
My bet: the cable housing is meant to go through the frame continuously.
One long piece all the way from the lever to the caliper.
Let's not guess. The OP has the bike in front of him,
1) What frameset is that
2) Is the cable and housing "guided" all the way out to the back of the exit? If not the rear brake exit should have a removeable stop. If it doesn't your frame is missing 2x stops.
3) Modern pinarellos (e.g dogma) will appear to take cable and housing full length through the top tube but this is incorrect. The frames come supplied with frame stops.