RE: [CR]Calculating Trail

From: "Roman Stankus" <rstankus@mindspring.com>
To: "'Mark Bulgier'" <Mark@bulgier.net>, "'Rick bernardi'" <rixtir@yahoo.com>, <classicrendezvous@bikelist.org>
Subject: RE: [CR]Calculating Trail
Date: Fri, 3 Mar 2006 06:51:07 -0500
In-Reply-To: <9327C3B25BD3C34A8DBC26145D88A90702CE54@hippy.home.here>
Thread-Index: AcY+gWl2usvdvIXHQl+Nkkfvzzr9FQAKJeAwAAOgISA=

This is a great site that makes it super easy. Go to

http://www.kreuzotter.de/english/elenk.htm

Roman Stankus Atlanta, Ga

-----Original Message----- From: classicrendezvous-bounces@bikelist.org [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of Mark Bulgier Sent: Friday, March 03, 2006 5:55 AM To: Rick bernardi; classicrendezvous@bikelist.org Subject: RE: [CR]Calculating Trail

The mysterious "Rick" of Anytown, USA asked:
> Does anybody know how to calculate trail?

Not sure if it's really on topic -- but what the heck, they did calculate trail back then...

Anvil Bikeworks has an Excel spreadsheet you can download at http://anvilbikes.com/story.php?module=calculators

Or just whip out your trig tables and calculate it yourself with: Trail = W/tan(H)-R/sin(H) Where W = wheel radius (hub axle center to the ground), H = Head Tube Angle, and R = rake

Wheel radius should ideally be measured with your weight on the bike, thus it varies with tire pressure - but nobody needs to know their trail that accurately. It's just not that sensitive.

Mark Bulgier
Seattle WA USA