It all depends on the course and the weather but...
I'd say I'm a slower amateur. Here's a nearly 40k one I did last year: https://www.strava.com/activities/1092306691; the only other female doing that course that day came in at 1:07:22
By contrast, here's my bike leg from a 70.3 earlier this year: https://www.strava.com/activities/1737709713
I think if I did that first course again I would be faster, mainly from increased confidence and better handling from more time spent actually training on the TT bike.

Edited to add: you may find the TT age standards helpful https://www.vtta.org.uk/content/0-standards

Thanks Scheherazade, good work by the way!

The age standards look good to me for the 10 mile TT. 25min for men, 28min for women.

If you are a FB user (or if you can see public posts), go to Uncle Tren's race productions. Tren hosts a monthly TT -- first Sunday of the month is 20k, and summer also has a 40k on Saturdays; I've done both. All ages and all levels show up, including tandems, recumbents, public and licensed women, etc. He posts a photo showing (handwritten) results usually by the end of the day, although you'll have to review a bunch of months to see enough women to get a sense of the times. It's super fun and very supportive, and also a great way to go all out on the same course.

Good time is the fastest that you can go! ;-)



You can pull up results of time trial races by cat/age grade at road-results.com

https://www.road-results.com/?n=results&map=0&region=all&racetype=4


Provides weather conditions day of, and results. You have to look up course distance and elevation separately.

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No coasting in running and no crying in baseball

You could always go by w/kg to avoid course bias. If you're on Training Peaks you can look at the Power Profile data.
You can also compare your w/kg over certain distances with the Coggan chart - https://www.trainingpeaks.com/blog/power-profiling/