It is marked constant curve.
Googling seems to suggest it is actually constant curve, before NP started talking "relatively constant curve" to actually mean "flex tip" cos in gtheir mind the tip should flex more and all that debate.
So - this is about a 1999 - 2000 ish mast. Forgetting that it is not high performance, will normal no cam freeride sails say 2000 - 2010 age from most manufacturers work on it as it is actually CC?
Or is it not....?
In which case - if it is not, and it is actually a bit tip flex maybe newer NP will work OK on it?
This is what I think I know about these masts ( think )
what size is it ?
The longer lengths are constant , the shorter they go the flexier top they are.
460 and up work great with constant sails , smaller I don't know.
If they haven't fried in the sun or stored in a hot roof truss they are a strong mast.
Select to expand quoteka43 said..
I think I remember these buggers being 23IMCS??
Just a guess Mark
No IMCS is the standard 25 for the 460 like all masts
They are still a standard normal SDM - just wanna know if they have the typical NP tip flex curve. I suspect not.....
I believe that the specifications of this mast are as follows:
source:mytrims.com/masts/data.asp?ID=239
An easy way will be to measure the weight against this and it is likely it is around 1998 in my opinion.
I believe these masts were manufactured by Fiberspar in the USA for Neil Pryde.
The 430 Freeride mast which replaced this with "light tip technology" was introduced by Neil Pryde in 1999 which was based on the C30 (1998) with the following specifications.See last mast entry on the LTT Freeride mast which replaced your mast.
I hope this helps. I have a NP World Cup MKIV 5.5 1993 (brand new never used) which may work with some tuning on your NP C30. Its for sale on seabreeze.
Mark, I use a backup mast which is older than that even. Looks the same, probably out of the same factory, is red, but is called a Neil pryde "Shock". Bought it new and in 20 years haven't managed to snap it. It still works on more modern Neil pryde gear. I also use it with 2014 KA 7.9 race and it's fine. (But obviously a bit heavier)
so, I think these old red C30/shocks are similar and probably compatible curves for newer NP gear.
I had a C30 460 of similar vintage and looked the same as the one which Mark has (just longer) and it worked fine infact really well on a 2013 KA Koncept 7.5 m2. I think the masts of C30 were made between 93-98 at the same time as the CK series NP masts. As they were made by Fiberspar they are excellent durable masts.
ah, the mast dilemma 
ESPECIALLY NP ...
It seems there was a time when Barry Spanier was with NP and masts were considered hard top
Barry re-started MauiSails as hard top and now they are constant curve %^&*(
the new S2Maui Sails is also CC !!
somewhere the NP masts started getting labelled CC and we know NOW they are still flex top (one of the few remaining)
i mixed an older NP CC top with a flextop bottom with good results
i always say - if you already have the mast n sail, rig in the yard first and if okay .. try it on the water
joewindsurfer.blogspot.com/2008/07/masts.html
joewindsurfer.blogspot.ca/2016/03/have-mastssails-all-gone-cc.html
i did NOT like the MauiSails HT/hardtop on a CC sail like the SW Retro
thanks aribenasher, all that was printed on the mast but I doubted CC.
If they were made by Fiberspar, this will be the same as a Reflex3200 I reckon. Ie: real constant curve.
Possibly but the NP specs differed a little from the Fiberspar.
Fiberspar Reflex 3200 430 MastThe Reflex 3200 QT provides the price conscious sailor with a high quality product, good performance, and the Fiberspar name you can trust. All the lengths have survived years of punishment in rental centers around the world. Because of their proven strength.
Carbon content - 30%
Mark if it helps in an act of desperation when I had a problem with my 490 mast I used an even older then your CK30, NP 25% wave mast (1 piece 460) with an 8.5 Maui twin cam on a massive mast extention and it worked great. Tune by eye not the numbers. I was totally surprised how well it worked. A bit soft pumping but certainly powerful and totally stable enough.
I believe the NP C30 is definitely constant curve. I expect it would be similar bend curve to the earlier Carbon 60 Constant Flex masts which were one piece from 1989-1993. The Carbon 60 while one piece weighed 1.75kg. The main difference is that the diameter of mast changed at some point.
untill the size reaches 520 , NP are constant curve flex , or flex top.
the numbers for a 460 range from 14.8--16, or about 77/61
Due to this masts age it is probably flexer even.
fiberspar not in USA , nor do I think anywhere, never heard they made NP , or masts for anyone.
still own one they are constant curve ,i use them in ezzy lions 7.5 sets and feel like ezzy rdm .use to use in a old ka 6.5 and gastra gts 8.0 also worked well in a serverne 6.5 gator and a 5.5 se ezzy .they can take a beating but loose fine glass with age and will get into your skin if rubed
Select to expand quotegrich62 said..
still own one they are constant curve ,i use them in ezzy lions 7.5 sets and feel like ezzy rdm .use to use in a old ka 6.5 and gastra gts 8.0 also worked well in a serverne 6.5 gator and a 5.5 se ezzy .they can take a beating but loose fine glass with age and will get into your skin if rubed
That's a big range of use.
I have used them on larger NP and North and work great.
Just don't run your hand down the mast to get rid of the sand , cos its like hugging a cactus 
Classic awesome mast. 
I use to have that mast .brought it from Reg about 15 years ago when he had that shop on the canning hwy.mine was a 460 used to rig it on the old arrow race sails .they were a tough mast in there day.
Select to expand quoteImax1 said..grich62 said..
still own one they are constant curve ,i use them in ezzy lions 7.5 sets and feel like ezzy rdm .use to use in a old ka 6.5 and gastra gts 8.0 also worked well in a serverne 6.5 gator and a 5.5 se ezzy .they can take a beating but loose fine glass with age and will get into your skin if rubed
That's a big range of use.
I have used them on larger NP and North and work great.
Just don't run your hand down the mast to get rid of the sand , cos its like hugging a cactus
Classic awesome mast.
I thought the same, large range of use. North are typically CC , NP , have never been, and most masts don't enlighten their performance, of course a NP mast ^should^ be just peachy.
FWIW , I
the few NP sails I have had work nicely on HotSails masts.
sorry i forgot 2 sails,6.5 lion,also worked well in that, but did not work well in a ka 6.0 stealth,cambers would not rotate,mast new about 98.the reason so many sail, was we only ever used 460 size mast and most sails had turban tops,if we needed longer mast we stuck a piece of alloy on the top[gastra boom adjusters fitted well on the niel pryde] if shorter a hacksaw.
