Mountain Bike Cable Routing
ArcStrike
the cable installation would go faster, but as I look it over, I'm just not
sure.
This frame was designed to have 3 cables along the top tube, i.e. both gear
cables and the rear brake. I saw something on Sheldon Brown's web site...
crossing the cables to improve the routing!
"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.
I believe in hi article he was only referring to 2 cables on the top tube. I
wonder if anyone has experience applying this approach with 3 cables on the
top tube?
My initial thought was that the gear cables would be on the outsides with
the brake in the center... then you really have all 3 cables rubbing. Now
that I think about it, the brake might be run through the outer stops to
avoid the crossover.
Is anyone using this approach? How is it working?
bourned
under-the-downtube cable routing as found on most road bikes.
Along-the-top-tube cables probably wouldn't benefit from crossing.
Duncan Bourne
Cramer
ArcStrike wrote:
That artical was referring to two cables on the down tube, not the top
tube. When you have three on the top tube, don't cross them. When I've
seen this (the criss cross) done on a downtube, it was with a canondale
and the cable stops on the frame were angled inward so it was clear that
they were meant to cross each other. It's poor design in my opinion,
having your cables routed along the bottom of the down tube, where mud
from the front wheel gets caked on the frame.
Cramer
Eric Lafferty
Agreed.
Karl Frisch
Interesting. Bontrager always (BT) suggested "Crossing" the cables on
his top-tube routed frames. The difference is that the cables never
recross. The rear cable runs from the right lever, around the left side
of the headset, to the front left boss. From the rear left boss the
cable crosses around the seatpost to the right seatstay boss. The front
cable runs from the left shiftlever, around the right side of the
headset, to the right front toptube boss. From the right rear boss the
cable curves down to a boss on the right side of the seattube. If there
was a benefit to this routing, it was less frame contact and less
pinching of the housing at the headtube, and a smother more radiused
look to the housing.
Regards
Karl
Steve Bratsberg
right side, (typing without looking) the rear brake goes to the front left,
the rear shift goes around the head tube(on the left side) and then to the
front middle and to the rear right. The front shift goes to the right of the
head tube and to the front right - then crosses to the middle rear. I find
that the two cables barely touch and gives me a better run for the rear
shift as it goes down the seat stay. I also run thin plastic sleeve on
exposed wires. Haven't noticed any drop in performance - or any gain for
that matter - however when I was running with no crossing, the rear cable
would rub on the seat tube as the suspension went through its travel and I
thought the the angle and twisting that the cable went through was a bit
much and if things got a bit grimy - etc.
YMMV
Steve
--
-----------------------------------------
Steve
s.bra...@sympatico.ca
"ArcStrike" <kjzac...@home.com> wrote in message
news:Ww3C7.128370$NT3.13...@news1.rdc1.ct.home.com...
Jeff
> The criss-cross cable routing method solves a problem found with
> under-the-downtube cable routing as found on most road bikes.
>
> Along-the-top-tube cables probably wouldn't benefit from crossing.
Actually they do, and here's why:
The main reason I cross my cables is because it means that the
housings do not touch the head tube and therefore do not rub against
the headset as much as they would without crossed cables. I have done
this on my Specialized, Trek, and now my Brodie frame. It works!
jeff