# Singlespeed & Fixed Gear - Where are frame geometry angels taken from?

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cycliques
03-21-07, 03:22 PM
Hello everyone,

Newly minted member here.

Just wondering where the angle measurements are taken from when describing frame geometry. Example: A 75 degree head tube. It can't be the angle on the inside of the tt and ht because its obtuse. Is the angle measured by imagining the tt passing through the head tube and measuring the angle on the other side? ie: the supplementary angle to the obtuse angle?

Thanks

dutret
03-21-07, 03:25 PM
most bike manufacturers have a diagram with the geometry specs they list.

dirtyphotons
03-21-07, 03:29 PM
75 degrees between the headtube and horizontal ;)

dutret
03-21-07, 03:30 PM
uhhhhh yeah what was I thinking

Shiznaz
03-21-07, 04:11 PM
heaven of course!

cycliques
03-21-07, 04:25 PM
Thats what I figured, thanks.

dijos
03-21-07, 04:57 PM
heaven of course!
nice catch.

Fixxxie
03-21-07, 04:59 PM
heaven of course!

Or Hell, depending on what kind of angels we're talking about :D

eddiebrannan
03-21-07, 05:13 PM
Hello everyone,

Newly minted member here.

Just wondering where the angle measurements are taken from when describing frame geometry. Example: A 75 degree head tube. It can't be the angle on the inside of the tt and ht because its obtuse. Is the angle measured by imagining the tt passing through the head tube and measuring the angle on the other side? ie: the supplementary angle to the obtuse angle?

Thanks

can you really not figure this out all by yourself?

12XU
03-21-07, 05:18 PM
can you really not figure this out all by yourself?

Somebody stole his protractor! Give him a brake...

Aeroplane
03-21-07, 06:01 PM
Somebody stole his protractor! Give him a brake...
WINNER!

cycliques
03-22-07, 11:51 AM
can you really not figure this out all by yourself?

Just looking for confirmation, man.

Fixxxie
03-22-07, 12:03 PM
Somebody stole his protractor! Give him a brake...

a BRAKE?