http://www.hirekogolf.com/jforum/posts/9.page JForum - http://www.jforum.net I noticed that in the data tables of Shafts Listed by DSFI, that none of the tempo or swing length columns match the "standard" DSFI. Yet in the write-up preceding the tables, it implies that the full swing length with fast tempo matches the DSFI formula (use factor of .97 to 1.02).

Why don't the standard DSFI and "Fast Tempo" columns agree?

And by the way, thanks VERY MUCH for continuing to produce this data each year.
thanks,
Brad]]> http://www.hirekogolf.com/jforum/posts/2969#7776.page http://www.hirekogolf.com/jforum/posts/2969#7776.page
Is this in the addendum or the catalog? If it is the catalog, the ranges for steel shafts went from medium tempo to 3/4 swing, while the graphite shafts are from slow tempo to fast tempo. The addendum will supercede the catalog in these cases.

Jeff Summitt]]> http://www.hirekogolf.com/jforum/posts/2969#7779.page http://www.hirekogolf.com/jforum/posts/2969#7779.page Driver shaft - Aldila Gamer R
DSFI..................85
3/4 Swing..........83
Fast Tempo........88
Medium Tempo...92
Slow Tempo.......98]]> http://www.hirekogolf.com/jforum/posts/2969#7780.page http://www.hirekogolf.com/jforum/posts/2969#7780.page
Here is the math:

3/4 swing 85/1.02 = 83
Fast tempo 85/0.97 = 88
Med tempo 85/0.92 = 92
Slow tempo 85/.87 = 98

In reality it is broke down this way, for a 3/4 swing the range is of swing speed or 79-83 (lower end is 85/1.07 = 79). For the fast tempo the range is 83-88, moderate 88-92 and slow is 92-98.

Jeff Summitt]]> http://www.hirekogolf.com/jforum/posts/2969#7782.page http://www.hirekogolf.com/jforum/posts/2969#7782.page
Here's how I think of it (and Jeff correct me if I'm off base)...

The DSFI number is exactly what the acronym indicates--an index. The index number doesn't REALLY indicate a swing speed. It's just a way to quantify the results of Jeff's number crunching that converts frequency, tip/butt deflection, resistance to torsional force, etc. to something useful.

It's the multipliers that Jeff lists above that, with some knowledge of a golfer's swing characteristics, converts the index into a useful swing speed.

Of course that number can be tweaked further as clublength and swingweight are adjusted from what Jeff uses as his "standard" for testing, but that's a whole other can-o-worms.



--Ron]]> http://www.hirekogolf.com/jforum/posts/2969#7795.page http://www.hirekogolf.com/jforum/posts/2969#7795.page Been out of town......thanks for the replies. ]]> http://www.hirekogolf.com/jforum/posts/2969#7860.page http://www.hirekogolf.com/jforum/posts/2969#7860.page