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RGB Roll bar requirements.
tiffshaw - 16/1/09 at 09:42 AM

Hi

Can someone advise me. Is a single roll bar with a brace down to the passenger footwell sufficient for MSA regs to race in the RGB series?

Chris


procomp - 16/1/09 at 10:51 AM

Hi

In short NO. The bars down to the passenger foot wells ( petty struts ) are now actualy not allowed by the MSA. And neither are rose joints as joints on the cage as used by many on there rear stays.

Minimum is a roll hoop with front or rear stays in 45mm x 2.5mm or 50mm x 2mm.

Cheers Matt


fesycresy - 16/1/09 at 12:41 PM

So Westfields RAC bar isn't allowed by the MSA ?


procomp - 16/1/09 at 01:05 PM

Hi

I should have also said that the min requirements for MSA spec also requires a diagonal from the lower side of the passenger side of the roll hoop to the upper on the drivers side.

Re the Westfield RAC Bar. Yep it is not MSA compliant as discussed on the WSCC .LINK TO RELEVANT DISCUSSION HERE

Cheers Matt


andylancaster3000 - 16/1/09 at 01:12 PM

quote:
Originally posted by procomp
Hi

In short NO. The bars down to the passenger foot wells ( petty struts ) are now actualy not allowed by the MSA. And neither are rose joints as joints on the cage as used by many on there rear stays.

Minimum is a roll hoop with front or rear stays in 45mm x 2.5mm or 50mm x 2mm.

Cheers Matt


Matt, is that to mean that petty struts are not allowed at all or not as a substitue for the rear stays?

Cheers,
Andy



[Edited on 16/1/09 by andylancaster3000]


Ian-B - 16/1/09 at 01:47 PM

As most RGB cars are non-standard cars and the series regs calls for min requirements of blue book, effectively braced fore and aft of the cockpit with equal protection for driver and passenger, (or rear braced if you use the standard car rules), at the tube sizes Matt quoted.
It's not clear to me from your description whether you just have one brace from the centre of the hoop to the floor (as was sometime used in the past), if it is this set up then it won't satisfy the effectively braced requirement for a full width roll hoop.
If your set up is a brace from each side of the hoop (close to or on the corner radii) to the floor (via suitable mounting) and a diagonal brace, providing your tube is correct you should be OK.
I would strongly suggest that you contact either the RGB eligibilty scrutineer (listed in the regs) or use the form in the regs.


procomp - 16/1/09 at 02:58 PM

Hi

Re petty struts. When i was at the last meeting with the MSA regarding rollcages etc petty struts where brought up in discussion as being a cause of many problems in acidents. I will have to go through the minutes of the meeting to see exactly what was going to be done about them. But for sure fitting them alone is not sufficient and fitting them with two rear stays was being questioned.

All in all regulations regarding roll hoops and cages has changed significantly since 2004. Many scrutineers officials car manufacturers and roll cage manufacturers do not seem to be keeping up to date with the changes. This is leading to many competitors spending money on Kitcars designed for competition use and rollcages etc that do not comply with even the bare basics of what is now required by the MSA / FIA.

If you require direct answers as to wether you roll over protection system ( ROPS ) is fully compatible with current regulations consult the MSA direct. As i say many oficials / scrutineers are not fully up to date.

Cheers Matt


alistairolsen - 16/1/09 at 03:11 PM

So if building for road and track days, with an eye on the msa regs you would want to go for a rear roll hoop in the required 50mm tube, two rear stays, diagonal from pass lower to drivers upper and make sure its 65mm or more above your helmet height?


procomp - 16/1/09 at 03:29 PM

Hi

That would cover the basics yes. The actual MSA regulation is 50mm Min above your head when wearing your helmet. I used the extra 15mm ( 65mm ) so you would be within the required regulation if you where to be measuring of your bonce without a helmet ( in case you had not got one to hand ). The line that you need to be below is from the top of the roll over hoop too the next structural component forwards. Usually the top of the engine is what is referred too in a front engined car.

Cheers Matt