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KA Koncept mast compatibility?

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Created by srtgumbee > 9 months ago, 16 Mar 2017
srtgumbee
112 posts
16 Mar 2017 9:42AM
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I would like to know if anyone has used a Hotsails maui mast or XO sails mast with a KA Koncept and if so has this been a successful match?

I see the current KA masts are 13.5%

I'm looking at compatibility with 2016 Koncepts, I have a 92% 430cm hotsails maui hotrod RDM (specified bend curve = 14) that may work on a 6.6 Koncept.

Also have a 80% 400cm XO RDM which is only slightly more flex top than KA according to the Unifibre chart...if that chart can be trusted. I'm considering this for a 5.4 Koncept

I'm trying to measure these masts myself to confirm bend curve....fun times :-)

Any insight to real world results with different masts would be appreciated. I also have my doubts on the 80% rdm (weights 2kg), it may be a bit 'dead' for the Koncept?

My end use would be powered up Slalom sailing, and speed sailing on a slalom board in an inshore harbor/estuary (not flat water, but I hope to find some one day). I weigh 70Kg and have been sailing on and off for 20 years. Cheers.

John340
QLD, 3363 posts
16 Mar 2017 12:40PM
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According to the unifibre mast selector, KA are constant curve and both HSM and XO are slightly more soft tops.

www.unifiber.net/masts-selector

AUS4
NSW, 1287 posts
16 Mar 2017 2:20PM
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XO should be fine.
Hot Sails, no.

azymuth
WA, 2154 posts
16 Mar 2017 5:02PM
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Select to expand quote
srtgumbee said..
I would like to know if anyone has used a Hotsails maui mast or XO sails mast with a KA Koncept and if so has this been a successful match?

I see the current KA masts are 13.5%

I'm looking at compatibility with 2016 Koncepts, I have a 92% 430cm hotsails maui hotrod RDM (specified bend curve = 14) that may work on a 6.6 Koncept.

Also have a 80% 400cm XO RDM which is only slightly more flex top than KA according to the Unifibre chart...if that chart can be trusted. I'm considering this for a 5.4 Koncept

I'm trying to measure these masts myself to confirm bend curve....fun times :-)

Any insight to real world results with different masts would be appreciated. I also have my doubts on the 80% rdm (weights 2kg), it may be a bit 'dead' for the Koncept?

My end use would be powered up Slalom sailing, and speed sailing on a slalom board in an inshore harbor/estuary (not flat water, but I hope to find some one day). I weigh 70Kg and have been sailing on and off for 20 years. Cheers.




I use / used Hotsails Hotrod RDM's in my 7m and 6.2m 2015 Koncepts - 430 for the 7m and 430 bottom with 400 top for the 6.2m.

Perhaps the sails rig a little flatter beneath the boom than they would with the perfect mast, but I doubt there's any speed penalty.

Happy with the setup and the HotRod RDMs are super strong. JJ

Windxtasy
WA, 4017 posts
16 Mar 2017 7:10PM
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I found the 2016 Koncepts to be quite mast specific. I upgraded from 2010 Koncepts to 2016 Koncepts and the masts which worked well on the 2010s (one NP and one I was sold as a KA but had no branding on it) did not work in the 2016s. The sails would not rotate properly. I ended up buying two new KA masts - which are great, and the sails rotate well.

mr love
VIC, 2404 posts
17 Mar 2017 1:25PM
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I really can't offer much to the conversation as we have not tested on those masts and I would only be speculating. Sorry.

sailquik
VIC, 6165 posts
17 Mar 2017 1:57PM
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I have used masts almost identical to your Hot Sails 430 mast (made in the same factory with only very slight layup difference) for quite a few years on KA Koncepts from 5.8, to 7m. but mainly the 6.6m. Mine all test right on 14% and are about one point stiffer than the KA mast and the standard Hot Sails Maui mast.

The only difference I can tell when switching from the KA mast to my other masts is that the other masts are 200 grams heavier, but it is hard to notice. The feel while sailing is extremely close.

I think it will work perfectly in the 2016 6.6m Koncept.

I have not tested the XO mast and don't know them, but I did extensive experimenting with with my 4m masts with a 15cm tip extension on the 2016 and 2017 5,4m (and 5.8m) Koncepts. Adding the tip extension and removing some length off the bottom of the mast effectively made it more flex top and slightly softer. It tested at around 16%. The sail felt very comfortable with a slightly deeper profile down low and looser leech with more twist. It pushed the draught further forward in the sail down low which made it feel more stable. In short, it felt good. But, I have reverted to using the standard masts in the 5.4m (and 5.8m) because they are definitely faster. Moving the lower draught forward and making the sail more "Knuckled" felt nice, but was slower.

So my advice is that a more flex top mast will work OK, and may feel OK, but it will probably be not as fast. I have also found that 80% RDM masts are nowhere near as nice a feel as the 92 -100% masts, but that may be a more personal thing, as I actually quite like the 70-80% SDM masts over the 100% SDM masts.

sailquik
VIC, 6165 posts
17 Mar 2017 1:59PM
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I have used masts almost identical to your Hot Sails 430 mast (made in the same factory and mandrel with only very slight layup difference) for quite a few years on KA Koncepts from 5.8, to 7m. but mainly the 6.6m. Mine all test right on 14% and are about one point stiffer than the KA mast and the standard Hot Sails Maui mast.

The only difference I can tell when switching from the KA mast to my other masts is that the other masts are 200 grams heavier, but it is hard to notice. The feel while sailing is extremely close.

I think it will work perfectly in the 2016 6.6m Koncept.

I have not tested the XO mast and don't know them, but I did extensive experimenting with with my 4m masts with a 15cm tip extension on the 2016 and 2017 5,4m (and 5.8m) Koncepts. Adding the tip extension and removing some length off the bottom of the mast effectively made it more flex top and slightly softer. It tested at around 16%. The sail felt very comfortable with a slightly deeper profile down low and looser leech with more twist. It pushed the draught further forward in the sail down low which made it feel more stable. In short, it felt good. But, I have reverted to using the standard masts in the 5.4m (and 5.8m) because they are definitely faster. Moving the lower draught forward and making the sail more "Knuckled" felt nice, but was slower.

So my advice is that a more flex top mast will work OK, and may feel OK, but it will probably be not as fast. I have also found that 70-80% RDM masts are nowhere near as nice a feel as the 92 -100% masts, but that may be a more personal thing, as I actually quite like the 70-80% SDM masts over the 100% SDM masts.

jimbob SA
SA, 999 posts
17 Mar 2017 9:05PM
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I've used a hot rod 430 in my older 011 5.8 koncept and all good, you being only 70 kilos it will be fine.

Alewi62
QLD, 158 posts
17 Mar 2017 10:17PM
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I have used an xo rdm 460 100% with my 7.5 koncepts for quite a few years. It works well.

srtgumbee
112 posts
18 Mar 2017 6:23AM
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Thank you for everyone's input!

I think I will use my Hotrod and may get a KA rdm for the 5.4, noting the XO will probably work, but the 100% KA would be 500gms lighter and provide the best 'feel'.

Ka have a 100 euro shipping fee to NZ (per order) so it makes sense to order as many items as I can afford rather than buy 1 item now, then another soon after.

Now that I have an idea of what masts I will use and I only need to buy 1 mast, I'm reconsidering what sizes to get....might get a discussion going on that too

BSN101
WA, 2374 posts
26 Sep 2017 10:12AM
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Is anyone using NP masts in KA cambered sails?

Im looking and a KA Race but already have NP mast at the correct size. It will be a light wind set up <20knts.

mr love
VIC, 2404 posts
26 Sep 2017 12:57PM
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Can you measure your NP mast??? If you could I coud answer the question, anything else would be speculating.

Sparky
WA, 1122 posts
26 Sep 2017 11:10AM
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I use X9 s and they work well. 460 in 7.9 and 490 in 8.7.
I know many others in WA who also use NP with KArace

BSN101
WA, 2374 posts
26 Sep 2017 11:44AM
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mr love said..
Can you measure your NP mast??? If you could I coud answer the question, anything else would be speculating.


NP FLX 2016 490.
Into KA Race 8.7 2016 or 2017.

Cheers Dave

Sparky
WA, 1122 posts
26 Sep 2017 12:25PM
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Actually, my 8.7 is 2016 and it's a 2016 flx 490 ( not x9)

BSN101
WA, 2374 posts
26 Sep 2017 1:24PM
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Sparky said..
Actually, my 8.7 is 2016 and it's a 2016 flx 490 ( not x9)


sounds like a green for go on the KA 8.7.

What sort of top end wind does it handle?

Sparky
WA, 1122 posts
26 Sep 2017 2:50PM
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I'm 6'2" and almost 100kg, still comfortable in 20knots, but not much more. They are quite powerful sails. I use it with a 130 isonic 2015. I have got airborne a couple of times recently while exploring its top end.

BSN101
WA, 2374 posts
26 Sep 2017 4:18PM
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Sparky said..
I'm 6'2" and almost 100kg, still comfortable in 20knots, but not much more. They are quite powerful sails. I use it with a 130 isonic 2015. I have got airborne a couple of times recently while exploring its top end.


5'11" about 90 kegs and on JPSL78 & SB US147. might be the go. Cheers

dkeating
VIC, 277 posts
28 Sep 2017 12:47AM
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BSN101 said..
Is anyone using NP masts in KA cambered sails?

Im looking and a KA Race but already have NP mast at the correct size. It will be a light wind set up <20knts.


I used NP X6 460 mast on 011 koncepts 6.6 and 7.5 for years and always rigged nice and felt good and I know others to who said they work well even thou the experts say there not ideal.
The newer model koncepts with wider luff sleeves/stiffer cams could be different thou.



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"KA Koncept mast compatibility?" started by srtgumbee