Is it possible to figure out a power estimate for a bike portion of a race, without a power meter? If numbers were supplied, such as rider wt/bike wt total, avg speed, distance covered (miles), total time elapsed? Would there need to be anything else that would be effecting the numbers? It doesn’t have to be exact, just a close estimate. If it isn’t possible, no problem, just figured I would ask all the minds that are good with numbers…
wind, elevation change, rider and bike drag at various yaw angles
basically no
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You’d be talking about a lot of factors…a lot of factors. You could get a “guesstimate” by looking at someone who is similar to you, on the same course with roughly the same time on roughly the same setup. However, you’d only get a final Avg. Watts since your efforts during parts of the course would be different. Again, this would be a complete shot in the dark…
Good enough for me…thanks guys! I will have to wait to get back on the computrainer to get some numbers. Need to get the ok from the wife to buy a Quarq, but not at this time 
I will just keep going off of HR/RPE…
Is it possible to figure out a power estimate for a bike portion of a race, without a power meter?
I think that’s called “iBike”
If you use a website such as Strava, they ‘estimate’ your power, and in a perfect world given all the physical parameters of your ride you could, in theory, calculate it yes. This may work ‘ok’ for specific scenarios (i.e. a very steep hill where you are moving very very slowly), but in practical terms… you need a power meter. Even if you could estimate your average power for a whole ride based on weight, approximate drag coefficients, heart rate, etc, etc, just knowing your average power barely scratches the surface of what power training is all about. It may be good for the ‘gee-whiz’ factor as some others have called it, but to really train effectively with power you need the nitty gritty details that only a PM and good analysis software can provide.
If you have a Garmin Edge series GPS, I believe you can get within 10% if you combine that data with SportTracks (free!) and this plugin ($10), provided you are an anal engineer or the equivalent navel gazer type…
Especially if it’s hilly and low wind (your ride, that is).