Flex vs. CPM's

I would like to know as well. But more importantly is there a conversion or general chart between brands and how they clamp/measure CPM in their shafts? I.E. Aldila generally measures 5 CPM less than Diamanas etc.

This is a chart that I use in general for drivers at a 5" clamp and being 45" long with a grip installed. Don't know how accurate it is, but my dad, brother and myself fit on the chart...where I think we should.

Ladies - ~235

Senior - 240 - 243

Regular - 246 - 250

Regular + - 252 - 255

Stiff - 258 - 262

Strong - 263 - 266

X-Stiff - 270 - 275

Here is what I've generally seen for 46" graphite shafts:

L, A < 240

Regular 240 - 259

Stiff 260 - 280

X-Stiff > 280

This is a chart that I use in general for drivers at a 5" clamp and being 45" long with a grip installed. Don't know how accurate it is, but my dad, brother and myself fit on the chart...where I think we should.

 

Ladies - ~235

Senior - 240 - 243

Regular - 246 - 250

Regular + - 252 - 255

Stiff - 258 - 262

Strong - 263 - 266

X-Stiff - 270 - 275

Wow according to this chart I don't think my mid 90 mph swing speed will be able to handle a 266 CPM Epic 68 that I have on the way.

I have a shaft flex chart I am trying to copy and paste but it won't hold the format, any help and I'll put it up.

This is gripped and AVERAGE with a 5" clamp

Remember as thewitt said this is just one part of the shaft profile and doesn't equal flex.

266 CPM as measured by Grafalloy for the Epic shaft might not be 266 after you have glued it into your driver head.

1) Your head might be heavier than the test clamp.

2) They might have used a different clamp position, other than 5", in their measurement or a different tip weight.

3) Did they measure the CPM with or without a grip?

4) When these measurements were made, they didn't take into account all the different kick points of new modern shafts. For example, a MY Whiteboard X and Blueboard X will not have the same frequency, as they do not have the same shaft profile.

All theses factors, plus many more are going to adjust the final frequency and playability when installed into your club.

266 CPM as measured by Grafalloy for the Epic shaft might not be 266 after you have glued it into your driver head.

 

1) Your head might be heavier than the test clamp.

2) They might have used a different clamp position, other than 5", in their measurement or a different tip weight.

3) Did they measure the CPM with or without a grip?

4) When these measurements were made, they didn't take into account all the different kick points of new modern shafts. For example, a MY Whiteboard X and Blueboard X will not have the same frequency, as they do not have the same shaft profile.

 

All theses factors, plus many more are going to adjust the final frequency and playability when installed into your club.

That was just the number I pulled from some websites online, not sure what their testing process was. It's going in a Nickent 4DX head shimmed to .350.

Frequency is measured differently by almost everyone so it makes it tough to compare #s. It's not a good way to compare two different shafts or fit yourself as the rest of the bend profile will affect how the shaft plays. It's really only good for comparing two shafts of the same model.

Even within one shaft brand the CPM to flex isnt always the same, ie a S in one line maybe 255 and 250 in more game improvement line.

All shafts are different and go by different numbers

Rifle has there chart

True Temper has there chart (Black Gold Shafts)

KBS has there chart

Matrix has there chart

Accra has there chart

Rifle has a double wall and KBS single wall so those shafts cut at the same CPM # will play much different. You need to use the CPM chart for that companies shaft.

Frequency is measured differently by almost everyone so it makes it tough to compare #s. It's not a good way to compare two different shafts or fit yourself as the rest of the bend profile will affect how the shaft plays. It's really only good for comparing two shafts of the same model.

 

Even within one shaft brand the CPM to flex isnt always the same, ie a S in one line maybe 255 and 250 in more game improvement line.

This is shown is detail within the Hireko guide that I linked above.

I think CPM/Flex is a good starting point when searching for a shaft. But the bend profile of the shaft is much more important.

I recently switched from a Matrix Altus X-Stiff to a Matrix HD-6 Stiff. Big difference in CPM (270 vs. 255). However, I tipped the HD-6 1/2", which makes it play more like a STRONG flex. It also has a much stiffer tip than the Altus. So they play and feel much different, but at the end of the day, both chart out to a 7.0.

Remember when you see a butt frequency number, you are ONLY seeing one picture of the shaft.

Butt frequency does NOT equal flex.

You can define any arbitrary 20 cpm range you want as "R" or "S" and we can find a shaft that is higher or lower than this range and still plays to an "R."

-t

Brought my 4dx head in to get shafted with the Epic 68S and had them check the CPM with the factory SR3 stiff shaft still in it. It came out to 250. Also had my R7 425 with a stiff Speeder 569 checked and it came out to 247 fully assembled. Would the raw shaft as measured by manufacturers with a 5" clamp typically read a bit stiffer? I'm hoping the Epic shafted up at the same 45" finished length will come out to around 250 as well.

Thanks for all the replies. I take it that the ping shaft in regular flex reading 230 cpm (with head on) is more like a senior flex? Makes me wonder what the reading would be for a ping stiff flex in the g25.