STI Installation question

I'm new to bike mechanics and I'm attempting to install Ultegra STI
brifters. I know that the left brake cable (facing the front) is supposed to
cross in front of the stem to the top tube. The right would then go down
straight in side the loop from the left.

Do the shift cables go left to left downtube stop and right to right
downtube stop or does the left cross to the right downtube stop and right to
the left downtube stop?

If you did the crossover at the handlebar, wouldn't it have to be crossed
back before the bottom bracket?

Any help would be appreciated.

Jonathan Kaplan wrote:

I'm new to bike mechanics and I'm attempting to install Ultegra STI
brifters. I know that the left brake cable (facing the front) is supposed to
cross in front of the stem to the top tube. The right would then go down
straight in side the loop from the left.

Do the shift cables go left to left downtube stop and right to right
downtube stop or does the left cross to the right downtube stop and right to
the left downtube stop?

If you did the crossover at the handlebar, wouldn't it have to be crossed
back before the bottom bracket?

My on line article on cable prep and installation covers this. Here's
an excerpt:

"Criss-Cross" Cables

"Most bicycles with handlebar-mounted shifters run the rear cable
on the right, the front on the left. This causes some awkwardness in
routing the length of housing from the shift lever to the frame stops.
Due to the need to allow these housings to be long enough to permit the
bars to be turned all the way back and forth, the housings often wind up
making a reverse bend--for instance, the rear will go from the shifter,
which is on the right, swing forward and cross over past the centerline
of the bicycle, then back over to the right side of the top tube, before
heading down the down tube. These extra bends increase friction, and the
fairly forcible contact between the housing and the side of the top tube
can damage the finish.

"A neat solution to this is to run the cables "criss-cross" style:
The rear runs from the lever, (on the right) around the top tube, and to
the cable stop on the left side of the down tube! The front cable
crosses over similarly from the left side of the handlebar to the right
side of the down tube.

"The bare cables then cross one another under the middle of the
down tube, making an "X". The cables may touch where they cross, but
they will do so very lightly, since they are both straight...the tiny
bit of friction at this crossing is more than offset by the reduction in
friction in the smoother-flowing cable housings.

"This technique does not work with over-the-bottom-bracket cable
routing, but is doable with most newer bikes that have
under-the-bottom-bracket cable routing and cable stops mounted toward
the bottom side of the down tube."

The whole article is at http://sheldonbrown.com/cables.html

Sheldon "Criss-Cross" Brown
+-------------------------------------------+
| It's easier to be original and foolish |
| than original and wise. |
| --Gottfried Wilhelm Leibniz |
+-------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

"Jonathan Kaplan" wrote in message ...
I'm new to bike mechanics and I'm attempting to install Ultegra STI
brifters. I know that the left brake cable (facing the front) is supposed to
cross in front of the stem to the top tube. The right would then go down
straight in side the loop from the left.

Do the shift cables go left to left downtube stop and right to right
downtube stop or does the left cross to the right downtube stop and right to
the left downtube stop?

If you did the crossover at the handlebar, wouldn't it have to be crossed
back before the bottom bracket?

Any help would be appreciated.

Derailleur cables go to ipsilateral side - R to R, L to L.

Lou D'Amelio

Jonathan Kaplan wrote:
: I'm new to bike mechanics and I'm attempting to install Ultegra STI
: brifters. I know that the left brake cable (facing the front) is supposed to
: cross in front of the stem to the top tube. The right would then go down
: straight in side the loop from the left.

: Do the shift cables go left to left downtube stop and right to right
: downtube stop or does the left cross to the right downtube stop and right to
: the left downtube stop?

Please read Sheldon's post before this one. I organised criss-cross cables
on an older road bike and it worked elegantly. On my newer bike the
downtube is large oval section and the cables would definitely rub on it,
so that rules the possibility out.

There are millions of bikes working fine with right-right and vice versa
so that would be there recommended way to go. If you have the patience to
set up criss-cross that is fine too - and if you go that way and encounter
a problem it's no biggie to revert to conventional.

Cheerz,
Lynzz

Thanks for your advice. The worst case is I try it and it doesn't work, and
I could end up having to replace the cables or housing if they are too short
to move.

I started with a 1984 lugged steel Trek touring frame, and I'm gradually
turning it into a bike. It now has wheels, a cogset, a bottom brack/crank
installed (by the local bike shop), headset/fork, Installed brifters
without cables, and brakes (but no cables). I'm hoping to get the bike road
worthy in a month or two. (definitely before next biking season).

insure- Do the shift cables go left to left downtube stop and right to right
downtube stop or does the left cross to the right downtube stop and right to
the left downtube stop? BRBR

Yes, you can cross them which reduces the possibilitynof the housing rubbing on
the head tube, but not necessasry. And yes, if you cross the cables/housing
from the shifters, ya gotta cross the cables under the downtube.

Be sure you route the shift housing going to the right side inside the brake
cable housing tho-

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"