By Rick Schultz
Last time we determined correct length of caliper mounting bolts and placed an order. To get everyone back up to speed, the bolts came in!
Rear brake caliper is now installed, hydraulic cable run but not hooked up yet.
It’s coming together pretty quickly now.
Next items on the agenda are
- Install the chain
- hook up the hydraulic lines
- bleed brakes
- tune the derailleurs
- install Favero Assioma duo power meter pedals
https://cycling.favero.com/assioma - wrap handlebars
- pump up tires
- RIDE!
But first, the chain. Since we don’t have a chain to check, let’s calculate the length.
There are two methods, (a) simple equation and (b) rigorous equation.
SIMPLE EQUATION: L = 2(C) + (F/4+R/4+1)
Where
C = chain stay length = 16-3/8”
F = front large chainring = 52
R = largest rear cog = 34
L = 2(16.375) + (52/4 + 34/4 +1)
= 32.75 + 13 + 8.5 +1 = 55.25 or rounded to 55”
RIGEROUS EQUATION: 1 + (0.25*(F+R)) + 2* SQRT (C2 + (0.0796 * [F-R])2)
1 + (21.5) + 2* SQRT (270.2)
1+ (21.5) + 2*16.44 = 55.38” or rounded to 55”
Looks like chain needs to be 55”
Chain ‘cut’ to 55” and installed onto bike
Don’t forget to check if chain is omni-directional like this Shimano Dura-Ace chain is. If using this chain, lettering points towards the outside.
So, what’s next? You would be correct if you said adjust the front and rear derailleurs.
The FD is adjusted using limit screws and angular rotation, in order
- No cable tension – alignment to the chainring
- No cable tension – outside plate to big chainring
- Adjust cable tension
- Using shifter buttons, adjust LOW / HIGH limit screws accordingly
Lastly, let’s hook up and adjust the Read Derailleur
- Adjust cable tension (I used Park 3rd hand to pull firmly on cable.)
- Adjust End-Bolt
- Adjust HIGH/LOW (Or as Shimano calls them – Stroke Adjusting) bolts
Since I previously trued the hanger, this adjustment was super easy. Actually, with Shimano’s latest derailleurs, it literally took me 5 minutes to adjust both derailleurs.
Chain is the perfect length and this drivetrain will never be cleaner! Appreciate it now.
Next time, completing the hydraulic brake connections.
Coach Rick Schultz is an avid cyclist who trains, races and coaches in Southern California. Rick is an engineer by trade, and in addition to being a coach, he's a bike fitter and prolific product reviewer. He's the author of Stretching & Core Strengthening for the Cyclist and Bike Fit 101: Your Toolset for a Great Bike Fit in the RBR eBookstore. Check his product reviews website, www.biketestreviews.com, and his coaching site, www.bikefitnesscoaching.com. Click to read Rick's full bio.
Such a complicated process for cutting hte chain to length. The simplest is what SHimano used to supply with their instructions: Chain over big ring and small cog, make the pulleys vertical.. I’ll be out riding while you are still staring at your slide rule.. :^)
agree – chain only needs to be long enough to work for the largest gears – big front and big back.
yes that is ‘cross chained’ but still that is what you do to size the chain
approach carefully
ie, cut it too big then remove links til it just fits
no need for square roots of pi
Campy says put it on the big ring and the small cog and eliminate chain “droop”. Complicated formulas make no sense .when there is such a simple method.
That Asioma power pedal looks like a nice product. Have you tried it out?