I need to replace the Ouzo Pro fork on my Jamis Eclipse - original owner said it was a 2004, but it could be a 2002. The one that's on there now has a 40mm rake. That seems a little extreme for a road/triathalon bike.

Does anyone know the rake of the Ouzo Pro which was originally spec'd on this bike?

You need to know the head tube angle when choosing the best rake offset. A 40 mm offset is not extreme for modern road bikes with steep head tube angles. It will give you more steering trail than a longer offset. Longer trail means more stability. I have an Ouzo Pro 40 mm rake offset on my Trek that has a 73.8 HTA. I prefer the 40 mm to my previous 43 mm.
A 40 mm rake offset would be extreme for a layed back HTA as found on many older frames.

Al

Al1943, thanks for that info. I was guessing that it would be the other way 'round. I'll see if I can dig up the Eclipse's geometry. I remember locating it somewhere when I got the bike two years ago. Memory says that the head tube angle is c.74.

In any case I'm reassured re which Ouzo Pro to buy.

It doesn't matter what Jamis spec'ed on the bike, what's important is what you like.

If you want the bike to steer faster, get a fork with more offset - maybe try 43 or 45 if it steers like a dog now. If you want something to steer slower...you are basically out of luck.

Good luck.

40mm offset does seem extreme for a triathlon bike since they typically have slacker head angles around 72 degrees. But you called this a "road/triathlon" bike so maybe the head angle is not so slack. Whatever the head angle is, if the steering seems too sluggish for you, go to a larger offset. Otherwise stick with 40mm.

Got an email from Jamis. 40mm is spec'd, beginning at size 57. This bike is not for crits, but it's very stable on fast descents. That's ia good thing for riding in and around San Francisco.

Here is a link to a rake and trail calculator: https://www.kreuzotter.de/english/elenk.htm
Normally you would use metric measurements. Input must be in centimeters though rake offset and trail are usually expressed in millimeters.
I use to have an article that said neutral steering on a bicycle is at 57 mm of trail. Personally I prefer a trail in the mid 60's.

Al

What has been overlooked here is the fork length. Not all brands are the same, they vary from 365 to about 374mm. If you go from one extreme to the other, you could get no change in the trail or twice the change expected, with about a .5 degree change to the head tube angle.