UKGSA Forum

Hi,We are in the process of moving our webhosting and the site is currently down. It should be back up again early next week.Cheers,Ian

Date for your 2014 diary 24th MayWeb Site will be updated for Entries open on 1st Aug 2013....Max 30 adults (Soapbox/Side Hacks), +Gravity Bikes + Luge. http://www.borderbogie.co.uk/Cheers Rich

It is with great regret that here at BIGBA, we have had to cancel Annandale Cup this year on Saturday 29th June 2013 and Sunday 30th June 2013 due to a variety of factors and also due to circumstances out with our control.The main reason being a lack of competitor entries which meant that the event was no longer viable or feasible to run. We did not take this decision lightly as we realise that many of you will be disappointed as you are all very passionate about your gravity racing.Once again so sorry that the event has had to be cancelled, but roll on 2014 when hopefully we will have a full complement of gravity racers willing to take on the challenge of the Annandale Cup course.

I'd say think narrow, small and aero. something you can push off the line easily. You can sometimes find wheel covers on ebay but they don't always fit well. depends on your rim depth and the width of your hub.

looking good Eddie

Thanks for the tips. Scottish site is a great resource for information.CheersPaul

Other things to do;* make disks to cover the spokes on your wheels* put aerofoil fairings around axle beams etc* check out these books - http://scottishcarties.org.uk/Aerodynamic+Design+of+Soapbox+Racers

At those sorts of speeds, aerodynamic drag is your biggest problem so make it as sleek as possible. Blunt at the front and pointy at the back, and as small a frontal area as possible.On a straight course you don't need to worry about braking for corners, so all up weight is going to help. find the heaviest driver you can. Eat many pies.Rolling resistance is going to be a factor. The most important thing for rolling resistance is to have slick tyres and put as much air in them as you can. You may struggle to find high pressure tyres for 10" wheels. I'd want to be running somewhere around 100psi, and it might be worth the trade off of larger wheels if it means you can get higher pressure tyres.The marginal difference between ordinary bearings and ceramic is likely to be negligible. Only spend money on bearings when you can't make it any more streamlined. I'd just strip and clean all the grease from your existing bearings and run them with light aerosol PTFE oil in them. Solid axles won't have that big an effect on rotational inertia as the mass will be very close to the centre of rotation.Make sure your brakes are set up properly and don't drag.Some useful information on soapbox aerodynamics etc., can be found at http://scottishcarties.org.uk/aerodynamics+of+soapbox+racers

We've just held our annual Braidwood Billy Cart Derby and the locals didn't even make it to the open finals. That makes 2 years in a row we've been beaten by out-of-towners. We're only a small town of 1100 people so to regain local pride I want to build something that kicks a$$ at next year's event.Top speed this year was 47 kph and my cart (a converted Jason recliner lounge chair) did 37 kph so I have a long way to go but at least I was comfortable. The winning cart for the 2nd year running is called Whistler and it has a slim windcheater body with 10 inch bicycle wheels. It's rear tyres were pumped up to 90 psi, fronts were 70 psi. I want to build a streamliner similar to Whistler, running solid axles front and rear. Wheels will be 10 bicycle but with aftermarket bearings. I'm toying with the idea of bolting the rear wheels to each end of a hollow axle running across the rear of the cart and having the rear axle rotate in its own bearings. This would allow inboard brakes and therefore less wind resistance. It would also allow a thicker (stronger) bolt to hold the wheels on and with only 2 bearings it may be justifiable in buying ceramic bearings. 2 bearings would halve the rolling resistance of the rear end but the added inertia of the axle and bolts would have to be taken into account.The race is held on a straight bit of road over 450 metres so my cart doesn't need fancy steering, a solid front axle does fine. The rules allow any length and width but it cannot exceed 70 kg without driver. It must also have 4 wheels 2 up front and 2 at the back.To see the track, look at Gillamatong Lane, Braidwood, New South Wales on Google Earth. We race from the intersection at Sandholes road down to Araluen Road.If you go to the Braidwood Times site http://www.braidwoodtimes.com.au/story/1....lly-cart-derby/ you will see some pictures of the event including my racing lounge chair and Whistler.Any advice on building a Whistler beater will be much appreciated.CheersPaul

You'd love it this time of year. 3rd day of winter and I had to scrape the ice off the windscreen to get to work. They've predicted a top temp of 16C though. Isn't that a good Summers day in Oldham?

Feeling mighty glad I didnt offer free delivery.....

I ve just built my own gravity bike. Dead easy and cheap, and still competative for all that. I raced it at BBs ... fantastic fun, a great sense of speed and a chance to race... mano a mano.

Tickettyboo 2 for sale ready to go hope hubs with cartridge bearings, harness seat belt, cable disc on rear, slick tyres, battery horn a few spares, tyres pads,bearings,body panels , windscreen 400 test drive possible,I was 750 for wheels without anything else. contact me for more pictures and detailscan arrange delivery.I also have another cart with suspension a sidecar and loads of 20" wheels, new tyres slick and treads, tubeless rims, seat belts for sale I will list shortly watch this space Just having clear out too many projects and need space I am also looking for a good gravity bike. contact me with what you have must be ready to goPlease login to download attachments.

The camber doesn't worry me but it does remind me of a Triumph Herald rear angles. What does worry me is I'm in Australia and there is no way in hell I can get any of the great carts you guys build.CheersPaul

Thanks for sorting that Rich.Sportsracer, dont be alarmed by the camber on the rear wheels. it worked just fine but I will be altering the angle before the next race.

Where do I find the pictures for 2013? Their website only has 2010 and 2011 listed.

Thinking of breaking or selling my cart. Gonna build a world beater next time.I ve taken the canopy off it this season and fitted rear suspension. More fun to drive.Its a good solid car with proven race experience, Dalby , Cairngorm ,Border Bogies. Its a nice reasonably fast little cart thats very stable.I m thinking of 325. Its not a problem if no one buys it Ill just strip it for bits. I ll be racing it at Worlaby if anyone wants to see it. PM me if interested.I m based near Manchester.Cant seem to upload a pic. It ll be somewhere on the Border Bogies gallery 2013 no 3.

a video fron Bruno Menzi, swiss driver, made at On, europeen cup 2013https://www.youtube.com/watch?feature=player_embedded&v=sfIRHUqDZYothe track:http://www.youtube.com/watch?v=9bk07Ypx7GEan other:https://www.youtube.com/watch?v=ZAnU2xID9ZM&feature=youtube_gdata_player

see http://borderbogie.co.uk/ for some new news items (including why the TV crew will be there) and the latest entries.