Does cable housing length effect shifting

[Kingfisher]

I think I already know the answer, but I recently switched a super record 11 group to another frame and kind of kept the cable housing long. It shifts fine but not as crisp as on previous frame.

Should also mention that new frame is internal cabling if that makes a difference

[dustyrider]

Originally Posted by Kingfisher

I think I already know the answer, but I recently switched a super record 11 group to another frame and kind of kept the cable housing long. It shifts fine but not as crisp as on previous frame.

Should also mention that new frame is internal cabling if that makes a difference

The length matters when it limits the derailleur’s movement.

[Cicli]

Originally Posted by dustyrider

The length matters when it limits the derailleur’s movement.

Correct, cables long or short causing weird or tight bends.

[Kingfisher]

Thought so, thanks for input guys. That campy group is coming off this week and will be put on incoming Zanconato and I will be sure to shorten cable housing length.

[sales guy]

yes.

[Ronsonic]

IME, it isn't the length it's that bends; loops, S-curves and such are bad.

[sales guy]

Originally Posted by Ronsonic

IME, it isn't the length it's that bends; loops, S-curves and such are bad.

The length can change the curvature of the bends.

Length(bend) will mess with shifting. I never realized how close it needs to be till I had a tri bike in 1995 that i couldn't get to shift right. I called up Merlin and spoke to Rob and he asked me what the length of the frame to derailleur housing was. I told him and he told me it's too long. It was only 6mm too long. He told me about the big book of Shimano and what they need frame makers to do for their build so that Shimano components work well. The book listed that number at 292mm. If you measure the pieces that come in shifters, they measure 292mm.

Never realized it.

[YesNdeed]

Originally Posted by Kingfisher

Thought so, thanks for input guys. That campy group is coming off this week and will be put on incoming Zanconato and I will be sure to shorten cable housing length.

The precut length of housing intended for the chain stay mount extending to the rear derailleur, as part of the Campy Ultrashift cable/housing kit looked a bit too long to me, or so I thought. I then spent the next year having trouble dialing in RD shifting, and my mechanic confirmed that I had made too small a loop. After replacing it, shifting is back to Campy smooth, no cable cutting required.

[ultraman6970]

Is not about the length of the cable, but how u use the cable :P

[weisan]

Originally Posted by ultraman6970

Is not about the length of the cable, but how u use the cable :P

Ok Master Ultra, you would have to break that down into simpler terms for me there, because disciple has no idea what you are talking about.

[oldpotatoe]

Originally Posted by Kingfisher

I think I already know the answer, but I recently switched a super record 11 group to another frame and kind of kept the cable housing long. It shifts fine but not as crisp as on previous frame.

Should also mention that new frame is internal cabling if that makes a difference

Always better to be a little long than a little short, but not WAY long. PLUS make sure the ends that go into the levers is cut smoothly and the wee brass washer is still in the lever. Internal doesn't help often depending how it comes out, down by the BB.

5mm housing at the rear der vs 4mm and using brass ferrules helps too.

[sales guy]

Originally Posted by oldpotatoe

Always better to be a little long than a little short, but not WAY long. PLUS make sure the ends that go into the levers is cut smoothly and the wee brass washer is still in the lever. Internal doesn't help often depending how it comes out, down by the BB.

5mm housing at the rear der vs 4mm and using brass ferrules helps too.

As long as you use the correct inner wire tho. Found that to be an issue also.

[batman1425]

IME - Sram rear der. cable loops from the frame stop to the der. body need a much longer piece than might be expected for smooth shifting. Longer than the commensurate Shimano/Campy example for sure. Sram systems seem to have poor tolerance for ANY pinching or friction in this area.

[oldpotatoe]

Originally Posted by sales guy

As long as you use the correct inner wire tho. Found that to be an issue also.

Proper ended, 1.2mm der inner wires.

[Mark McM]

I agree with all the sentiments that the bends in the cable affect shifting more than the actual length of the cable, so you want to choose the length that gives the smoothest and least number of bends.

However, the length does still have an affect, due to increases in friction and housing compression. A tandem can have the same number of cable bends as a single bike, but the shifting on the tandem will always be a little lower in quality.