View Full Version : 503 questions

nickyd - n/a
15-Feb-06, 02:01 PM
Hi all,

Got a couple of questions about 503's.....

Anyone know the best way to mount them? Upside down with a gearbox, or the right way up with a belt drive? I had a 253 with gearbox which worked fine but was wondering if anyone had any views on it. Didn't know if it would be advantageous to mess around with pulley ratios?

Is the formula going to be recognised at the worlds?

Is anyone selling one?

Is there an optimum duct size?

Cheers for your help, although I know that was more than a couple of questions.....


Topaz - n/a
17-Feb-06, 11:50 PM
After some deliberation its been decided that f503 has been allowed as a seperate formula at the worlds. We at Team Topaz had a brand new 503 with a gearbox in 2004 and won 5 championships (3 UK & 2 European) with it in one year. We also won the 503 Championship in 2005 with the same craft. There is no best winning setup, just close and fast racing!

The jury is out on whether gearbox or belt drive is best, ( opening a can of worms?!).

Hope this helps?

Team Topaz http://hovercraft.org.uk/images/icons/smiley_icons/icon_rolleyes.gif

kiwikidnz - n/a
17-Feb-06, 11:56 PM
i have a older 503 points model and i want to know if anyone has had problems with a miss or 4 stroking in the mid to high range? What is the correct pitch for a single fan craft and the distance from the splitter plate??? the joys of owning a craft!

Iceman - n/a
18-Feb-06, 02:45 PM

the mis-fire / 4 stroking is probably due to an over rich mixture in the mid-range, try dropping the carb needles one notch and see if that cures it.

As for fan pitch, every setup up is different. The best fan pitch is always the pitch that allows your engine to run at max power at full throttle. For a 503 max power occurs at 6500rpm, so set your fan to give this rpm when holding the throttle fully open. If you want advice on a simple technique for setting your blades then please send me an IM.

I always aim for a splitter plate gap of 10-20mm.

Sean Atterbury - n/a
20-Feb-06, 05:06 AM
Hi, I have had all those questions to ask before, building my own craft from nothing has made that I have experienced it all, from blade clearance to engine trouble.

Go through past posts with my name on it, (Sean Atterbury or Atters ) there you should find all you need to know and will find that this board is full of guys who are willing and able to help.

I have never come across a bunch of people as great as these on the board.

Happy hovering.

Denise Talbott - n/a
20-Feb-06, 12:29 PM
Hi Nick

I notice that you are in Hertfordshire - where abouts? The Chilterns branch meet every first Tuesday at the Crooked Billet pub on the A41 between Aylesbury & Bicester at around 7.30 -8pm.

Why don't you come along and have a chat with the experts - Conrad of Conair sports will be there as well as Mark of Team Topaz!

Contact details via the brances link.

kiwikidnz - n/a
21-Feb-06, 03:37 AM
I am from New Zealand .Its cold and wet and the coldest day is in the middle of summer

nickyd - n/a
21-Feb-06, 09:55 AM
Hi Denise,

I'm in St. Albans. I would come to the meetings but tuesdays are not good for me.

Hopefully I'll get to talk to Conrad this weekend after rockin' at the AGM!!