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..reach? At the moment I have a 0 degree Deda Zero 110mm stem and the reach is fine but the height of the bars is a little too low. To counter this I'm eyeing up a new stem but I'm hesitating over what length. I'm sure 6 degree would be enough in height but obviously the same length stem (110mm) would shorten the reach.
Is there a simple maths formula for geometry or a maths genius on here who can help?
Basically, I'm trying to work out what length of stem I need to get the bars the same distance in reach but a touch higher.
I don't have the time funds or quite frankly patience to faff with different stems.
Thanks
It's negligible until you start going to 20+ degrees. Just stick with the same length.
To get the same horizontal dimension use 100*(cos 20/cos 26) = 104mm
So a 100mm will be 4mm shorter and a 110mm 6mm longer than what you have now.
Cos(angle)=A/H
H=stem length
A=reach
A=H*cos(angle)=110xcos6=109.4mm
Very much negligible! The six degree tilt will raise the bars by just over 11mm
It's also worth adding that (at least in the past), some brands accounted for the difference due to angle so a 110mm stem was the same distance from steerer centre to h/bar centre regardless of the rise.
Cheers fella's. Very helpfull
Ooops sorry I'd read 100 instead of 110 in your OP - add 10mm to my figures.
It's also worth adding that (at least in the past), some brands accounted for the difference due to angle so a 110mm stem was the same distance from steerer centre to h/bar centre regardless of the rise.
You mean horizontally? Not heard of that before.
Handy link..
http://www.brightspoke.com/t/bike-stem-calculator.html
Click on "Compare Two Stems" and enter the details.
I did see a better one once that showed you as a graphic, but can't find that one anymore.
self moderated.
Al - yeah, can't say I've heard about it for a while, hence the caveat but I definitely recall at least one company's reps explaining about it which I guess really does make more sense even if the differences are negligible and people don't really notice...
Cynic-al, did your calculation figure in the wotsit of the head angle (i.e. 90-70ish), hence the difference?
That website is top! Thank you.