HI guys what do you thing is the best way to measure your speed is? Is gps the way to go or can you rigg up up a wireless bike computor ,bike speedo's are a lot cheaper but for the small wheel size are they suitable, and whats the update speed of gps devices are they fast enough to get an accurate speed any help would be great.

As Test Pilot says, you should get a GPS that logs to memory or an SD card.

After you get home you can download your track to a computer, and make pretty pictures like this one:



A GPS also allows you to tune your gear -- if you have nice steady winds then you can run the same course, find your max speed, go back to the top of the course and make an adjustment. Lather, rinse, repeat
A bike computer would be OK for mucking around with, but really it isn't a patch on a good GPS. I figure that my sailing time is immensely valuable to me, and the price of a GPS is chickenfeed compared to the amount of value I get from it.

I would highly recommend the GT-31 by Locosys: http://www.kiteaction.com.au/vmchk/Accessories/Windmeters/Locosys-GT-31-GPS.html

If you're serious about measuring your speed, it can't be beaten. There is loads of software out there to help you analyse your tracks as well.

(Disclaimer: I run this website: gpsteamchallenge.com.au - it gets very addictive!)

Thanks for your wisdom the gps is method is definatley the way i think i will go but in the shot term it will be a bike speedo

I've done some r&d on gps's and thats what i will do, the bgt-31 i am very keen on i just dont like removing and inserting msd cards all the time especialy when there in a water proof conpartmet. but i also discoverd that with my smart phone nokia x6 it has inbuilt gps and with race chrono software you can map the track speed and all the good stuff then export the file in lots of formats including xml,you have it pretty much coverd.

racechrono.com/

All the phone GPS's that I've looked at aren't good enough for windsurfing - most of them don't record doppler speeds so they're not accurate enough for a worldwide competition.

They would be fine for a weekend warrior though