I have a few fly rods under my belt now and have been checking with the common cents method. 2 of my 6wt a TFO and Rod Geeks came in at ERN 6.08 one older unknown that was sold as a 5 wt came in at 7.40 and two 8wt NFC and Rainshadow came in at 10.24 . Amazed how my 6wt seem to line up and the 8wt seem over rated. Just a little inconsistent. Now with these numbers dies it mean I can step up line weight on the 8wt's and be ok?

All the rods are correctly rated, because there is no manufacturer system for rating fly rods. They are labeled by the manufacturer for the type of fishing and casting they designed the rod to be used for. If you can't get a rod to load at the distance you're fishing, there is nothing wrong, and it's even good, to perhaps up-line by one or two line sizes.

From what I'm seeing on the CCS power ratings (those aren't line numbers) your TFO and Rodgeeks 6-weight rods are intended for close to moderate distances with a 6-weight line. Your 5-weight rod is intended for medium to long distance casting (I'll bet it's a 9 footer) with a 5-weight line. If you're fishing in closer you should certainly step up to at least a 6-weight line. The NFC and Rainshadow 8-weight rods are for longer distance casts with an 8-weight line. If are fishing in closer with them, or can't get them to load for whatever type fishing you're doing, by all means step up to at least a 9-weight line and try that.

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Thanks Tom. I should have mentioned all are 9' as far as the 8wt goes with these rods line weight is kind of a moot point. They will be used for steelhead Chuck and Duck and Indy rigs.

My experience in measuring fly rods is that all of them I've measured from 3 different brands are all more powerful than the nominal for their described line wt. Some are into the next line wt significantly.

To answer directly your question, yes, you can, unless you are interested in making very long casts, go up a line weight to one that is consistent with your measurements for those rods that you have found out of range on the more powerful side.

The logic of considering these discrepancies a matter of the brands' intentions of using them for shorter or longer casts is flawed, in my opinion. It would be much better if they would keep the power of their blanks/rods closer to the nominal description and let us decide if we wanted to use them for shorter or longer casts. We have no way of knowing their intent. So in effect, we have no way of knowing whether their product will work well with the $100 line we buy based on their description of the rod.

In conclusion, custom builders would be well served by doing their own power ratings using CCS, which is not difficult, and buy their lines after testing the blanks, allowing them to tune the line to the rod power and their intended use without wasting a lot of money on a line that won't work well.

CF Burkheimer used to rate all his rods for 3 fly lines, i.e. 4-5-6, which was meant to show the angler than for in close use, go with the 6, average mid distances, go with the 5 and for long distance use, go with the 4. Simple and made good sense.

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That would be better than what we have now. What we have now makes no sense. It's just a crap shoot.