Bigger Bars - New Brake Cable?

New cable is the only solution I can think of, or stop making turns in that direction 🙂

sansabar said:

I run Ultegra shifters on my LeMond Buenos Aires. I recently replaced the Bontrager Race Lite 40cm bars with Bontrager Race Lite 44cm bars. One problem - now a sharp turn causes the front brake to engage due to the decrease in cable length. Is there a workaround for this or do I need to replace the brake cable with a longer one? Never had this happen before!

Scott

The front brake cable must be routed incorrectly. Under normal operation the front brake, fork, and bars all rotate as a unit and the path length, and thus cable tension, from the front brake lever to the brake remains constant. The rear brake cable path length, on the other hand, increases as the bars are turned to the right, thus increasing cable tension if the cable/housing is too short. If the rear brake cable or shift cables are routed in such a way that one or more is pulling across front brake cable, it could be preventing the front brake cable from moving as one unit with the fork/front brake. If a shifter cable runs across the brake cable, it could trap the front brake cable and thus increase the path length and cause the cable to tighten up when the bars are turned far to the left.

In short, check the path of the brake and shifter cables to make sure that they do not catch each other as the front wheel is turned. If everything is properly installed, turning the front wheel should have NO effect on the front brake cable tension. To remedy the problem, disconnect the front cable from the front brake, reroute it so that it is free of the other cables, reattach it, and readjust the brake.

Good luck

John M said:

The front brake cable must be routed incorrectly. In short, check the path of the brake and shifter cables to make sure that they do not catch each other as the front wheel is turned. If everything is properly installed, turning the front wheel should have NO effect on the front brake cable tension. To remedy the problem, disconnect the front cable from the front brake, reroute it so that it is free of the other cables, reattach it, and readjust the brake.

That was the first thing that I did. I thought that this was a stupid mistake on my part. But, no cable binding or path crossing. I believe that the difference in the new bar distance (2cm per side) along with slightly different cable grooves in the new bar have added up just enough to create this problem. I bought the bike used and I am assuming that the cables are stock, but the extended headset, larger bars, etc. have all added up to present me with no more "gimme".

Replacement cable is on the way. Is there anything I should know about changing the brake cable in an Ultegra shifter? Tricks, tips, etc.?

Scott