Stem calculation.
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Just wondering what tool people are using now yojimg appears to be dead. Wanting to work out if a bike with a 30mm taller 10mm shorter stack/reach can be worked out fit wise for a new training bike (new gen 58cm Tarmac > Diverge) Tarmac has 10mm spacers above the top cap if this helps, I'm guessing slammed with a -17 will get it close.
TIA.
Aaron.
TIA.
Aaron.
Using Tapatalk
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Spreadsheets... Google Doc to be specific:
- prendrefeu
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There is a spreadsheet doc which exists here on this forum (somewhere) that calculates Stack & Reach, taking into account stem height, length, angle, etc... you can compare between two bikes this way and make adjustments as necessary. You will need to figure out your own reach due to the handlebar change as well, that is not in the calculator.
I'll upload it when I get home unless somebody else can upload it before me.
I'll upload it when I get home unless somebody else can upload it before me.
Exp001 || Other projects in the works.
Assuming current set up:
2016 Tarmac S-Works rim
size = 58
stem = -3 deg / 110mm
steerer top cap + spacer stack height = 15mm
Handle bar mounting stack = 650.24mm
Handle bar mountain reach = 499.02mm
This will have the equal handle bar stack and reach:
2016 Diverge Pro
Size = 58
stem = -17 deg / 120mm
steerer top cap + spacer stack height = 10mm
Handle bar mounting stack = 651.66mm
Handle bar mountain reach = 501.97mm
2016 Tarmac S-Works rim
size = 58
stem = -3 deg / 110mm
steerer top cap + spacer stack height = 15mm
Handle bar mounting stack = 650.24mm
Handle bar mountain reach = 499.02mm
This will have the equal handle bar stack and reach:
2016 Diverge Pro
Size = 58
stem = -17 deg / 120mm
steerer top cap + spacer stack height = 10mm
Handle bar mounting stack = 651.66mm
Handle bar mountain reach = 501.97mm
The yellow cells are the inputs. Since I'm not sure what your exact set up is, I only guessed.
Someone posted this in other topic. I dont know if is what you want
http://ttbikefit.com/stemcalc.html
Edit: topic source @CBJ post
http://ttbikefit.com/stemcalc.html
Edit: topic source @CBJ post
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Thank you everyone, I appreciate the help. Anyone have the link to the google doc? I'm on tapatalk at present and can't seem to locate it..
At the moment im running a 120mm -6 stem on 10mm of spacers so a 130mm -17 without spacers should match if I'm not mistaken. Basically tempted to make the change to have an all weather training bike that can take 35mm tyres and fenders with ease but not lose too much of what I like about my Tarmac disc.
At the moment im running a 120mm -6 stem on 10mm of spacers so a 130mm -17 without spacers should match if I'm not mistaken. Basically tempted to make the change to have an all weather training bike that can take 35mm tyres and fenders with ease but not lose too much of what I like about my Tarmac disc.
Using Tapatalk
nefariousintent wrote: ... 120mm -6 stem on 10mm of spacers ...
10mm of spacers, does that include headset top cap? Those are usually 15mm, so total stack height would be 25mm.
SlamThatStem top cap (1.85mm) may be needed for the Diverge depending on what stem you can get. Not sure if they make one that'll fit Diverge's headset though.
Specialized's multi stem may be the most practical option, since they offer angle range from 8 to 28 deg.
btw this is my own spreadsheet, not sure if that's what you were asking for. PM me if interested.
- prendrefeu
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Exp001 || Other projects in the works.
having used yojimg quite a bit, i was interested the bbbikefit one took account of different head tube angle - so you could compare bikes.
I find bb2stem a little perplexing as i get different numbers between the geometry chart and the stack and reach chart
- i think this might be because some companies don't specify wether their TT length is EFF or not (the only reason i can think why the numbers are off)
I find stack and reach much easier to deal with, and would probably be nervous about matching a fit (pre-purchase) without stack and reach numbers
- of course there is likely a margin of error between manufacturers, but i doubt it could go much beyond +/- 5mm
one question about bb2stem spreadsheet for regular users...
... why "SPACERS + HEADSET + STEM STACK*0.5" what is STEM STACK and why are we using 50% of it in the calculation?
edit: typing this out i am guessing it is the width of the stem (to take us to the midpoint of the stem?) .... i guess in the spreadsheet Stem width is a constant???
I find bb2stem a little perplexing as i get different numbers between the geometry chart and the stack and reach chart
- i think this might be because some companies don't specify wether their TT length is EFF or not (the only reason i can think why the numbers are off)
I find stack and reach much easier to deal with, and would probably be nervous about matching a fit (pre-purchase) without stack and reach numbers
- of course there is likely a margin of error between manufacturers, but i doubt it could go much beyond +/- 5mm
one question about bb2stem spreadsheet for regular users...
... why "SPACERS + HEADSET + STEM STACK*0.5" what is STEM STACK and why are we using 50% of it in the calculation?
edit: typing this out i am guessing it is the width of the stem (to take us to the midpoint of the stem?) .... i guess in the spreadsheet Stem width is a constant???
Yes, you need to find the centerline of the stem and since stem clamps vary in width, you need to factor that in because it's like adding spacers.
I've used BB2. I liked using the downloadable Excel version better than the online version. It took a few minutes of working with it to fully understand it. I also had to find the unadvertised angles on my Colnago (super secret proprietary information though easy enough to actually measure). Why does Colnago have to do this???
I've used BB2. I liked using the downloadable Excel version better than the online version. It took a few minutes of working with it to fully understand it. I also had to find the unadvertised angles on my Colnago (super secret proprietary information though easy enough to actually measure). Why does Colnago have to do this???
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