steve gurney having a go at world speed record

www.3news.co.nz/Gurney-to-attempt-world-.../147032/Default.aspx

Saw it on the news last night to looks an awesome speed machine and i'm surprise its not been built like that before, though i do think it can be even more streamline than it is. There are apparently 3 teams from the major kite companies going to NABX this year to try and break the kite buggy landspeed record.

So Goodluck to Steve, Craig and the boys from Peter Lynn putting NZ kite buggying on the map.

i had it pointed out to me today the faring looks like an aerofoil in cross section, if that were the case the buggy could lift off at high speed, much like the intro to the "6 million dollar man" its meant to show steve austin crashing a plane, pretty sure its actually a US desert speed record gone wrong. I would be considering leaving the faring off to start with. My heart is with the PL crew, the buggy looks cool. Im surprised the rear wheels are not cambered in at 5 degrees or so and that the spokes are not covered in, i suspect mk2 will arrive in the desert looking even better. XXracer are making a buggy , libre and others. what ever the outcome it will be good for buggies as long as no one "6 million dollars" them selves. then us local lads could find it hard to find a welcoming beach. keep and eye on www.nabx.net 10 days to go !

we dream the dream.
they live the dream. go hard boys and kick some arse.

yeah is was wondering about the lack of camber too,
and if the small front wheel will have enuf grip.

but like the idea of breaks for the dry lake bed as i heard its hard stop/slide on such a gripy surface.

good luck guys,

Quick way to fix it would just be to vent the fairing/cowling in the right places. Otherwise as long as they take lots of spare tyres at least they should have a lot of fun trying and that's what it is all about. The x-rays should be interesting too.

Heck I'd try and set the record on a unicycle if it meant I was sponsered to go to an epic location like that for a week.

hell i'm the 9th fastest landboarder on the planet. some bugger needs to sponser me to go there so i can push butch off the top perch and break the 50mph barrier!.
hehehe. more dreams. we'll have to organise a speed week at baylys. thats our best shot for high speeds locally.

Jimmy22 wrote:


What would that achieve?
The theory that was explained to me by a couple of very knowledgeable folks is that raked wheels are slower. They scuff along sideways. Do you have some info that has passed me by?

Jimmy22 wrote:


What would that achieve?
The theory that was explained to me by a couple of very knowledgeable folks is that raked wheels are slower. Do you have some info that has passed me by?

some info here,

www.ozebiz.com.au/racetech/theory/align.html


but buggies and land yacht, are differnt from cars bacaues the kite pulls sideways.

main points, negative camber give a lot more side grip

but will tend to turn the wheel in and wear the tyer more on one side,
"toe out" helps fixs this.
most of the other promlems relate more to cars etc..

with a buggy on sand the advantages tend out way any disadvantages

make sense?

If you leave cars and land yachts out of it. What actual gain do you get from cambered rear wheels when going in a straight line. Surely minimizing drag would be paramount for a record attempt.

i've just looked at the tv3 report. thats one unusual design......
I would have thought if they were designing farings you would want to reduce the low pressure zone behind the rider? i would have thought a tail fairing would be the go. and wheel spats. but then again i am not a aerodaynamics engineer. so i bow to the wisdom of those who know better.

my theory goes, with camberd wheels you gain more stability, ther wider by footprint and they have less tendancy to tuck in a hard slide, i made mine for the moose, not for going faster but to increase stability wich inturn does allow you to go faser, this is obvius but you cant say camberd wheels will make you go faster...on a flat beach camber is irelivent, you would just make the axle wider if you needed more stability.
then to the contact patch issue, mototbike tyres are designed with a profile that increases the contact patch for grip when cornering, and lessens it for going straight....buggy tyres bo not have this profile change,(bigfoots may have a bit)they are basicly round...therefor the contact patch will remain the same no mater what camber you lean them...again making camber irellivent..

i believe camber is only an advantage on rough terrain by increasing stability in general,the only other benifit is its antituck tendancy and the toein toeout ability but any toein/out will increase drag.

i would argue that a dead straight wheel with a large rounded profile/contact patch is best for lateral loads..i have experimented with skinny tyres like these and (on sand at least) they are incapable of holding the lateral forces required to go fast in a kitebuggy...have no idea what theys be like on the surface they are racing on but to me, if argen had a drift on during his 127k with bald barrows then physics says if you reduce the contact patch more you will slide more.

then thers the whole surface are versus ground pressure thing that i have never fully understood but due to my history with cycling have always wonderd about....the idea is this...on tarmac...if i have a bald mountain bike tyre 2.5" across at 30psi and the contact patch is say 3square inches versus a half inch roadbike tyre at 100psi with a contact patch 1square inch witch has the most grip??...the mountain bike tyre has a huge contact patch but low ground pressure (think tractor) the roadbike has a tiny cantact patch but huge ground pressure (think train wheels)
both have heaps of grip but wich is more suited to kitebuggys??

who has done their homework??

as i understand it, a rubber tire tends to roll on itself on cornering or sideways pull of a kite.
a cambered wheel will counter this and give more grip than a up-right wheel.
so you can fly a bigger kite without carrying extra weight.

bit like when leaning a bike into a corner.

ha, i tried googleing it, and got pages and pages of, Equations of motion,...Lateral motion theory.... etc blah blah blah..............

more simple than that, when you want to scrub off speed a cambered wheel with zero tow in would put less weight on the spokes and not try to pop the tyre of the rim so much. no other reason. in speedway side chairs the 3rd wheel has huge camber, if it were upright you would see huge cart wheels pretty often . no other reason from my end. its possible the PL pod racer has super strong wheels with no need to camber and that the COG is lower than the axle center to avoid a flip. They left today for the NABX , good luck to them all. i have seen a few photos from the guys i regularly chat to such as PL and Ruudje of XX racer, some pretty nice ideas and buggies. i really hope they get wind, they deserve it.

Looks like there is a little camber after all:
www.stuff.co.nz/oddstuff/3502335/Gurney-...s-world-speed-record

The brakes puzzle me though!

read on the nabx site, due to the grip of the surface a sliding buggy can flip a lot easier than on sand etc.. so brake are a good idea to slow down, from a 130+kms

Like a slide caused by hitting the brakes at 130kph on the saltflats?

yep!

well it turns out that i might be going to the states this year (nov) for work. now i might just have to organise a stop over at vegas and bust some speed runs on this salt flat!!!!

ooh yeah i may yet get to live some dreams of my own..... yeha! anyone keen to tag along?

Here some pics of the PL speed machine from the nabx website.
Definitely made for the desert, look how low that buggy is, you'd be collecting heaps of seaweed on North Brighton with that one.


Check out Peter Lynn's number 2 buggy in the background (above pic) made back in the late 80's. things have come a long way since.