It seems a lot of us hover about just under 30 knots trying to make that breakthrough for quite sometime, then once past 30 they come along frequently. There must be some breakthrough in technique which allows a sailor to finally get past that 30 knot barrier.
Obviously you need enough wind, to bear away at the right angle, and flat water helps, but what else did you do differently to get past 30 knots?
Mine was reducing the size of the fin. I thought I needed a 32cm fin to provide enough lift to get going and stay going through the lulls, it turned out otherwise. I put a 29cm (mfc weedie) with my 5.8 and picked up the 3 knots I needed.
as said above setup is pretty key but the trick for you anita i think is to be a bit braver with your sail size choice, i know that you like your 5.8 alot but i think you should be trying to sail more powered up, use your 6.4 until you can't, as alot of people say you should rig for the lull's then the gusts are a bonus, as for fins it's about getting the right fin i recon that for your sonic you shouldn't go smaller than a 30 maybe 28 but my isonic 76 is fastest with a 30 even with only my 5.0m on it, if it's a weedy you can go a bit smaller but probably 26 or 24 are the smallest weedys i would go
but to be honest i think that you just need to go out very powered up (whatever setup that may be) and find a nice flat spot so you can bear away and sheet in
just keep trying and you'll get there soon
but some wind would be nice
Put as big a sail up as you can barely hang on to going back up wind and when I say barely hang onto I mean two hands up the front of the boom getting the sheet kicked out of you barely able to hang onto it in survival mode.
Then when you go down wind on your speed run you'll really be able to bear away.
Closing eyes helps as does riding the board like you stole it
Let the board do it's thing, light feet, don't fight the board just trim it flat so it's not digging a rail and creating more resistance to the sail.
When abject the terror arrives and the vision blurs, laugh at Huey, you'll have plenty of time to clean the crap out of your wetsuit after you've finished your 32knot dance.
Speed sailing is mainly attitude to sail faster than you've ever sailed before you have to sail at 110-120% of you capabilities, embrace that sheet is going to happen, it's rare but it will happen.
If you're worried, then you won't charge. So if you're worried then put on the right protective equip to better protect, helmet(a necessity) PFD or an impact vest (for the choppy howling days) which will give some more confidence.
Most importantly you may have to sacrifice a small child to get some decent wind
Anita, it sounds to me like you really, desperately need to take a trip to Sandy Point, or Lake George if it ever fills up again. With any kind of decent small slalom board your dream can come true. I would be surprised if you did not top 35 knots the first decent windy day.
Take to plunge and come to Sandy Point for the annual Speed Fortnight this year in the September/October school holidays. 
Oh, and if you are still not sure, watch this again :
www.seabreeze.com.au/forums/Windsurfing/General/Sandy-Point-A-Speedsailing-Movie/
come visit us in benderland next good front anita bit cheaper than going over east.
Sandy Point might be an option now I have a 5/3 wetsuit but I mean the kind of breakthrough that sees people regularly getting 30+ on the river when they had been stuck on 29 point something for sometime...
What do they do differently?
Sacrificing small children is quite out of the question...
What a lot of heavy guys don't realise is how much chop slows lighter people down.
Well at 70kg, that's where I place the blame for my lack of speed anyway.
And I'm sure Anita is a fair bit lighter than me.
Also most speed gear is aimed at bigger heavier people, those footstraps are probably too far apart.
Board trim is important, getting the entry point behind the front strap is hard if you don't have enough weight to sink the tail.
A few people have used aluminium bars to extend the front straps backwards with good results. (See Tom Chalko's page).
My fastest speeds are on a 5.3 metre sail with a fin around 20cm in flat water. with 25-30kts wind
Instead of going bigger Anita I'd try going smaller, (being in control is a big part of going fast) and looking for flat water with decent wind.
If we get a good day at yoyo's this Winter, that should do it.
anita isn't asking how she can get a pb in super special conditions
it's a similar thread to lao's except i don't feel it's worth me offering advice to him when he's a much better windsurfer 
any way i'm in a similar boat to anita, i weigh 55kgs and have mostly slalom kit to choose from probably most importantly no speed boards
the first time i broke 30 was a insanely fresh seabreeze on my smallest possible gear but in very lumpy water at pelican point since then i disagree that small is best my 6.2reflex and 57cm mistral and a soft 30cm pointer is just about the easiest kit for me to get over the 30 mostly because my 5.0 isn't any faster until it is properly windy and secondly the less extreme conditions often mean a tad flatter water
as decrepit said board trim is also very important for light weights, foot straps should be nice and close together (no need for mods) and the board should be trimmed flat yet it is important you still have enough fin to fly the board.
all up i think your extremely close to the regular 30's anita with just a bit of tuning and different gear selection you will be ready for when we do get some wind
and last of all if your really desperate a bit of lead in your life jacket can help when you are over done but this does make everything but straight sailing alot harder and therefore sessions can be shortened alot hope this helps
How come on my gps i only register 30 or 31 max and and slow coaches like Scarrgo get greater speed?
is slowboat 10 plus knots quicker? A couple at a push,must be a conspiracy.
First time I did over 30 knots was on a 5.3m non cambered sail with a 84 litre 55 wide slalom board in small chop and yes once I had done it once it was much easier to to again, I realised just how broad off the wind you need to go but the thing you do need is WIND. I have a 6.4 Koncept also and have never got it over 29.5 knots (no matter how hard i try) and Im 60kg. i used my 6.4 yesterday on my 84 litre slalom board again with a 29cm fin in choppy water (similar to swan river) and couldnt get past 28 knots. I am sure if i had changed down to my 5.7 I would have got another knot or 2 (but was getting late in the day so gave it away). I was really super overpowered heading upwind but just felt like I had drag and didnt have the weight to keep the board in control off the wind through the chop.
I agree with Decrepit that boards are not designed for the light weights. straps on all my boards feel like they are possibly too far apart and not out board on the rail enough to really trim the board as my feet are too short and if i want to get my heel where it should be i only have tips of my toes in the straps.
Anyway i just thought I would say that I have never gone over 30 knots on anything bigger than a 5.7m sail and any board that is bigger than 84 litres. I did manage to get 27 knots out of a 105lt 67 wide lorch yesterday but that was scary as.
I too am chasing the 30 knot mark. Currwently at 28.5 which was done on a 99L carve and a 5.8 Koncept (cambered sail) with 32cm fin in 25-30 knots
been sailing for 2 years. Usually other windsurfers on the same day are around 10 knots in front of me.
I think cambered speed sails certainly help a lot, epsecially with windsurfers who are relatively new to the sport, however they are harder to rig, de rig and water start.
One thing I have noticed is as you get used to going fast and it doesnt scare the hell out of you as much it does get easier.. for example once I done 25 I repeated that twice within months. Then once I hit 28 it was repeated 3 times in the one session.
Having a good coach to help with your stance and trim is a great thing...
Sheet in, bear away and rig for the lulls.... I think 
.... baby steps
It took me ages to reach the 30 knot barrier, it seems to be a mental barrier as well as a physical one. I read everything I could, asked faster guys how to do it, I was getting guys I sailed with asking me why I couldnt reach it with good gear etc. I had nothing, didnt know why etc. Then just had a big can of HTFU one day and went for it. Sailed Long Reef in the morning, then rigged at Lake Dangerous on slalom gear. Took the advice Id been given, did the crucial thing, went OFF the wind as hard as I could (just OK) but it worked and finally saw 30.3 on the GPS. That seems to be the big thing, bear off and try and push it.
Once you hit the 30 knot mark, it actually seems easier to get back there and then try and push it for the next level. Unfortunately it gets harder after that
Hey Anita,
I'm in agreement with Pepe about using a smaller fin (as that is what works for me - at 75kg) but appreciate it may be different for others.
I've done a quick check of my fastest speeds because they were done on a Sonic 85 (the same as yours) and were only just the other side of 30kts. Achieved using a JP speed 28cm and a Select SL7 27cm.
Not using the Select all that much since getting the JP. Happy for you to borrow it and see if it works for you (as an alternative to your 28cm FO weedy).
P.S. PB's were achieved on a day wth very solid gusts and pretty flat water (even for Melville.
Terry
i find sail set up makes big differences . i got big improvements when i started down hauling a bit more got faster and then one day i put on some more batten tension and camber spacers and got a nice improvement too , just getting it dialed in so its powerful and balanced so it just all glides over the chop with out having to think about it
I was lucky enough to have achieved 30 kts or the first time a just few days ago. Exciting for me because for a long time I had not been able to get past about 26 kts. Recently however I have been using larger sails, smaller fins, sailing overpowered, and heading downwind a little (nothing extreme) and the speeds have been increasing. I don't think that slalom gear is required for 30 kts (for middle-weights at least): I used an Exocet Cross FSW board, the stock 29cm fin and a 6.5 Ezzy Cheetah no-cam sail. It was also very, very windy for that setup so I'm not sure if i will be able to do it again 
.
Probably a slalom board and cambered sail would allow you to go fast on all points of sail though, not just downwind like the FSW.
That's the sort of information I am after. Keep it coming!
Hopefully RayGun is reading this too (he is currently on 29.96!).
I got a display of 30.1 once but it was knocked back to 29.6.
You need to think about what is holding you back on each and every run. This is how I got through 30kts. Is it board control, lack of power when you go off the wind or do you just feel like you can't hold enough power on the run?
Think about what is holding you back on every speed run then figure out how to fix each problem one at a time.
If you are lacking power on the downwind run then go bigger, if you feel you can't hold enough power then there is to much drag and you need to change your setup. It could be as simple as trimming the board or changing fins.
There is no magic fix, everyone is different and you are the best one to figure it out.
In my opinion you need reasonably consistent wind, flat water, sail size that challenges you in the gusts for that day, suitable fin and then just go for it when a gust comes through. It took me ages to crack the 30. Got it this year and still haven't hit it again - because we just haven't had the wind on the days I could sail. I've noticed that the guys who manage the higher speeds sail a lot of ks to do it. Which means they are (more often than not) on the water at the right time a gust comes through to lift them over the 30's, 35's and 40's.
I hover around 92kgs. Got the 30 on 2nd January on a Futura 101 with 7.0m Lightning and a 38cm fin.
windxtasy if you have a nice smother than normal water on your sesh with a good wind your chances are greater with board handling not such a problem be positive with a you can do it approach and it will happen your no different than the rest of us 2 legs and 2 arms and the reward doing it is the same as feeling it happen happy days ahead !
Sail tuning by someone who knew what to do helped me. I went months just under 30 and was convinced I could not do it. Then one day I needed to get over 30 ( as Pepe had done so), and I asked Peter Dans for help. He tweeked my sail and I immediately gained 3 knots. The trouble is I still have little idea about how they should look when rigged so I rig to the settings recommended on the sail. This is despite repeated tips from really knowledgeable sailors.
Keep at Windxtasy, you will get there.
