I have a '18 Diamondback Release 3. Great little bike. Stock Pike easily upgraded from 150 to 160. So I got a 1 degree angled headset and the new air spring. I was wondering if there is some kind of online modeler where I could pump in all the stock measurements/angles, then play with them to see how each effects all the others. Here's a link to my bike's stock numbers, size Medium: https://geometrygeeks.bike/bike/diamondback-bicycles-release-3-2018/
Online modeler/calculator to analyze changes due to increased fork travel/length?
- Thread starter Chuckolicious
- Start date
Generally, 10mm of additional ATC height will net ~.5º slacker HTA, maybe similar on STA but maybe a little less, ~2-3mm more BBH, and an ever-so-slightly shorter ETT and reach.
I think these numbers are correct or at least close. Maybe someone like @mtg or one of the other nerds on this forum can chime in.
But to directly answer the question, I do not know of any online tool that does what you're asking.
I think these numbers are correct or at least close. Maybe someone like @mtg or one of the other nerds on this forum can chime in.
But to directly answer the question, I do not know of any online tool that does what you're asking.
As an example (and this isn't where I got my figures above but is kind of a decent example) have a look at the Yeti SB130 vs. SB130 LR. Same frame, but the LR version has a 10mm taller fork. It also has a spacer removed from the rear shock to get additional travel, but the eye-to-eye of the shock is the same so that shouldn't affect the numbers.
geometrygeeks.bike
Geometry Geeks
The world's biggest open geometry database. Find bikes by name or numbers. Easily compare bike geometry side-by-side.
geometrygeeks.bike
Bike Geometry Calculator
Web app made for recording and comparing bike fits and frame geometries.
www.bikegeocalc.com
Well FKNA.
Bike Geometry Calculator
Web app made for recording and comparing bike fits and frame geometries.www.bikegeocalc.com
bike geometry calculations is the reason why trigonometry is one of the few mathematical disciplines I have stayed proficient in.
Very cool, but now I'm totally confused. Of course I was hoping I'd get something I could easily pump in those published numbers into and then just mess around. Now I actually have to give this some thought and figure it out.
Bike Geometry Calculator
Web app made for recording and comparing bike fits and frame geometries.www.bikegeocalc.com
But just in case anyone knows of a simple one, I'd still be interested!So I figured it out to some degree, but am stuck in the loop of changing one starting measurement effecting others I have put in, so I can't put in my stock numbers. I'm thinking there is a specific order to do it in, but can't figure it out.
The thing with bike geometries is that the way the angles are you can run some basic estimates that will still be accurate within a fraction of a mm.
Assuming you are riding a size large, an increase in fork travel of 10mm will raise your handlebars 9mm, slack your head angle .44 degrees and raise your bottom bracket height 3.3 mm. Those numbers will not change all that much between sizes.
Those calculations were not done being 100% mathematically exact. But the difference will be within .1mm.
That is just looking at a longer fork. If you put a longer fork on with a 1 degree angleset, about the only thing would change is the HA. Your reach and TT length could get shorter by a few mm depending on the angleset you are using and how many stem spacers you run.
I recently did the same on a bike with similar geometry, although starting with a 160mm fork. I really enjoyed the results. Bike feels so much better on the fast and steep stuff and more precise on the slow technical stuff. The only possible drawback is I feel a little more flop while climbing.
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Thanks man, this helps!