Straddle cable lengths

[feetabix]

Remembering my physics lessons......force x perpendicular distance to fulcrum and all that......the 90* angle should be formed between cable hanger at its connection with straddle cable, clamping point on the canti and the canti pivot point.....discuss!.....

 

[feetabix]

Wd's set up is extreme, but it looks sweet!.....I'd spend my ride looking down at it, admiring its elegance and shine......surely that is the main point!.... .....I spent two hours on Sunday autosol'ing my stheno rims and spokes until I could brush my teeth in them.....a waste of time some may say but they look ace!....

 

[We_are_Stevo]

I think the correct length is whatever length allows the straddle cable to form a ~90 Degree bend..

The optimum braking efficiency is achieved when the angle between the straddle cable and the canti' arm is at 90 degrees; as is the case in the photo' posted in the above quote...

...the angle at rest is just under 90 degrees so that the slight movement it takes to contact the rim achieves the optimum angle; which is not really that difficult to set up by eye alone

 

[FluffyChicken]

there are lot's of 'angles' on a canti arm

 

[We_are_Stevo]

there are lot's of 'angles' on a canti arm

I think the correct length is whatever length allows the straddle cable to form a ~90 Degree bend..

The optimum braking efficiency is achieved when the angle between WHERE the straddle cable and the canti' arm JOIN is at 90 degrees; as is the case in the photo' posted in the above quote...

...the angle at rest is just under 90 degrees so that the slight movement it takes to contact the rim achieves the optimum angle; which is not really that difficult to set up by eye alone

Happy?

 

[Marcus W]

yeah

90 degrees it is - definately!

 

[skoda2]

I don't believe exact angle matters much so long that proper braking power and modulation is achieved.
Cheers

 

[We_are_Stevo]

I don't believe exact angle matters much so long that proper braking power and modulation is achieved.
Cheers

That's how it's achieved...

 

[FluffyChicken]

there are lot's of 'angles' on a canti arm

I think the correct length is whatever length allows the straddle cable to form a ~90 Degree bend..

The optimum braking efficiency is achieved when the angle between WHERE the straddle cable and the canti' arm JOIN is at 90 degrees; as is the case in the photo' posted in the above quote...

...the angle at rest is just under 90 degrees so that the slight movement it takes to contact the rim achieves the optimum angle; which is not really that difficult to set up by eye alone

Happy?

Actually no
That's just happy coincidence that on that style of canti it happens to look like a right angle.

I think most above say what most manufacturers e.g. shimano try to achieve. The two straddle length make a right angle at the centre point (be it imaginary or not, straddle widths vary) at some point in the 'brake in contact with the rim' stroke. This gives the their best power to cable pull ratio meaning you have plenty of lever to play with.
Of course levers pull varies.
So err just play around that point.

I hope my icecream softens up soon, getting bored waiting to dish it out.

P.S. I do have various sketches/drawing's of imaginary lines and angle where people and companies work and debate it out.

 

[WD Pro]

I would be interested to see where the perfect 90° would run through - canti stud / canti to cable fixing / straddle ?

WD