Miter Sheet Translation ?

[Epicus07]

Looking at a custom BW and am torn about how it has a level bar drop with my usual saddle height and a short heat tube.

Can anyone generate a stack and reach based on this miter sheet ? I assume it’s to scale so CAD or something could accomplish this ?

[PortlyPuncheur]

I use bikegeocalc.com for these tasks.

[Mark McM]

I get a Reach of 359.6mm and a Stack of 509.4mm (based on the assumption of a 10mm lower headset stack). Effective top tube length 515.3mm

But someone should double check my numbers.

[C40_guy]

Originally Posted by Mark McM

I get a Reach of 359.6mm and a Stack of 509.4mm (based on the assumption of a 10mm lower headset stack). Effective top tube length 515.3mm

But someone should double check my numbers.

Are you sure about the TT length? Wouldn't that 54.75 get longer, not shorter with a horizontal bar?

[donevwil]

deleted, 448.5 dim is what I needed.

[spoonrobot]

If you print it out 100% portrait orientation it is almost exactly 1:100 scale. Incredible, or perhaps the program was designed as such. Either way I am impressed.

[spoonrobot]

ETT 555
Stack 565
Reach 387

This is to the top of the headtube and not the hypothetical headset cup

ETA: Please see post #30, the drawing displays only the bare headtube with no measurements for estimated headset cup thickness.

[Mark McM]

Originally Posted by C40_guy

Are you sure about the TT length? Wouldn't that 54.75 get longer, not shorter with a horizontal bar?

Oops! You're right, I was using the value 513.2mm (which is the top tube from miter to miter, not center to center). Using the 545.5 C-C top tube number, the effective top tube is 558.0mm.

Crap! I got Stack calculation wrong, too! (But the reach should be right)

Stack should be 547.5 x sine( 78 - 73 ) + 532.5mm x sine( 73 ) = 557.0mm
Reach should be 547.5mm x cosine ( 78 - 73 ) - 532.5mm x cosine( 73 ) = 389.7mm

[Epicus07]

Thanks everyone,

Maybe I’ll just average the results and hope for the best ? :0

Measurements from seller:

TT: 54.5cm (CTC)
ST: 51.5cm (but compact geo) CTC
Crank to Saddle: 728mm w/ estimated level bars
HT: 14cm
Stem spacers: 20mm + 2.5mm on top
Stem length: 90mm
Chainstay: 430mm

[spoonrobot]

Well don't do that the numbers Mark McM gave you are way wrong

Measuring in high resolution with Gimp I get

ETT 559
Stack 563
Reach 388

[donevwil]

OK, just saw the 448.5 dim:

eff TT 559.6
Stack 581.8
Reach 381.7

(stack and reach being to the top center the HT)

[spoonrobot]

I only have my cheapie travel calipers but they seem to agree with the pixels. Please excuse the parallax.

[Epicus07]

You guys are the best.

[C40_guy]

Originally Posted by Mark McM

Oops! You're right, I was using the value 513.2mm (which is the top tube from miter to miter, not center to center). Using the 545.5 C-C top tube number, the effective top tube is 558.0mm.

I get lucky sometimes. Once I got an answer right in high school AP Physics.

Once.

Seriously.

...this is why I'm a sales coach, not a rocket scientist.

[spoonrobot]

The most important consideration for Breadwinners is; what livery? Some of the paint options are excellent and some are not so great.

I saw this specific bike in person and was taken aback by how good it looked IRL.