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MG Midget and Sprite Technical - Midget Roll Bar Problem

Help please! After nearly 16 years my 67 midget is nearly ready to fill with fluids and fire up. But now I have a problem. Sometime over the last 10 years or so I bought a roll over bar from MGOC. It fitted fine until we tried to refit the refurbished hood frame and new cover. The bar was around 2 inches too tall.

In the hope that I may have ordered the wrong one all those years ago I ordered another one just last week-end. It has arrived and you’ve guessed it it’s identical to the last one and doesn’t fit.

I’ve called MGOC who have agreed to take the new one back but can’t supply any alternative and can’t offer any explanation as no-one else seems to have a similar problem.

My 72 Midget has a roll over bar fitted which fits fine but is a very different design. Unfortunately, I’ve no idea where it came from as it was on the car when I bought it.

A photo of the MGOC bar is at http://tinyurl.com/63rrq7 and one of the unidentified one fitted to my 72 Midget is at http://tinyurl.com/5jjsl4. Can anyone identify the one fitted to the 72 car as this design will definitely fit the 67 car? Alternatively, does anyone know where I can get a bar in a different design to the MGOC bar that might fit?
WC Mexson

I can be no help here, but I'd love to know where the one you currently have fitted to your 72 came from - and if it's functional and not just aesthetic - as it's a nice look. If you find out, let me know.
Rich Amos (1330cc Blaze Red '72)

The one on your 72 car looks very like one I have made by John Aley of Aleybars (who were subsequently taken over by the late Tony Fall of Safety Devices).

The design was intended for motorsport use, but that was the club motorsport of 30-odd years ago: it will not give the protection of modern rollover bars designed for motorsport. However, it can be more convenient on a road car because it lacks crossbracing. Correctly mounted with reinforcing plates, the fact that the rear legs feed onto the rear box section 'chassis' members I believe can make quite a strong structure.

I suspect that although the MGOC rollbar looks strong, structural engineers tend not to be so keen on this kind of design (over to you, guys!).

Tom
Tom Coulthard

Tom, great info.

I'm not a fan of the MGOC bar personally. I'm not quite confident in the concept of a bar without a diagonal as if enough force is exerted on it sidewards, it could theoretically buckle at the bend.

I'd be interested in your recommendations for the best 'performing' bars which can still fit under a hood. I like the cross bracing personally and I've even considered a partial cage for the road car before (door bars, or diagonals from the roll bar to the front cross members on the floorpan) but simply have not had the facilities to fit any form of bar, although likely will do soon when we move.
Rich Amos (1330cc Blaze Red '72)

Tom, you're a genius. The bar on the 72 car does have the remains of a manufacturers sticker attached and from what can be seen it almost certainly said "Aleybars". Now all I have to do is find someone that can make one up or has a used one for sale.

The Safety Devices website doesn't refer to anything similar as they seem to concentrate on full cages now which would be overkill for the local Club events that I intend to use the car for.

I'm still very open to suggestions and ideas from others and will welcome all comments.

Rich, watch this space for any further developments.
WC Mexson

Bill's earlier bar looks as if it is quite strongly diagonally braced - because the rear braces look as if they rake outward, with what look like decent welded joints. I reckon that shape will be easily as strong as the mounting points.

I like the look of it, too.
Nick

I picked up ,one like your 72 car has, off e-bay a few months ago for £40. So its well worth keeping your eyes open. Have you tried speaking to Peter May? He shows FIA rear roll bars on his sight but no price. I believe the FIA bar is like the one you have but with an extra diagonal bar. You may need an FIA bar if you are going to compete! It may also be worth having a look on the FISC website for advice or parts for sale, they tend to have the older cars.

Cheers Carl
C Bintcliffe

Have you welded a repair where the forwards-most legs go? I was wondering if the repair was (as often seems to happen?) not to the original shape.

Just a thought.
rob multi-sheds thomas

The 'MGOC' bar looks very similar to the Aley bar i fitted to my midget in the 70's (1275) but it was covered in black leatherette/ foam and called the Aero type.

I have one in my current midget (RWA)and i think it is also an Aley aero - no badges. Clears the hood when up, slightly tight to folded hood frame when down.

When refitting it into the Heritage shell the base fixing plates needed a bit of 'persuading' to fit onto the wheel arches properly.

Richard.
richard boobier

I agree that the bar without bracing is less strong than the one with - the question is really how much difference this would make in a real-life incident (and how would we know with so many variables?).

I rolled my MK I in July 74, and survived, so thought next time I'd try to increase my chances, so BRB has had an Aley Bar for many years. (Mind you, if I'd been wearing a seatbelt my roll-over accident, it would almost certainly have been a different result!)

Anyway, that's the woffle part of this post. The real bit is:

- did you know you can adjust the roof frame for height and angle? You may be able to find some additional space for your bar... mind you, 2" is a lot of space to find...


A
Anthony

Many thanks for all the comments and suggestions - all of which will be followed up. In answr to Rob's question the MGOC bar has not been changed at all, they're as supplied.

I will post the solution once resolved. Meanwhile please keep the ideas coming just in case........
WC Mexson

If made of the right material (in my case, 1.5" ID pipe, 4mm wall thickness) the diagonal brace is not needed for strength ..... been there, proved that in two separate fairly quick roll-overs in my B (80 mph, 95 mph) in one of which the car landed heavily on the outside of the top corner as it went over. (Moral: don't try to avaoid spectators standing in dumb places in the stage) This was back in the days when the brace wasn't required for that spec pipe, and spectators weren't controlled either!

In the B (or Midget) the bar is much shorter bottom to top, in a full saloon body it is higher and does need the brace. The Midget is much lighter too, so the loadings are correspondingly less. For road use, if the material is correct I wouldn't bother with a brace.
Paul Walbran

When I came to fit my bar it was evident that this situation could easily arise. The bar height is determined very much by how far back you position the feet on top of the inner wheel arch. Of course you have to balance this with moving it forward so that the forward feet are just about touching the bulkhead floor and the bar is getting very close to the back of your head. So, move the bar forward, slightly further down the wheel arch slope until it clears the hood and bolt it in there. I have to make up some 'spacers' the the heritage shell inner wheel arches were not identical height!
Robin Cohen

This thread was discussed between 12/04/2008 and 16/04/2008

MG Midget and Sprite Technical index

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