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Arnie · 03-17-08, 06:46 PM

Ian,

I'm also looking at an RCR and have found a few helpful individuals, here in Blighty, willing to let you plant your backside in the car.

I have done this and have a big problem getting my 5"11 94kgs of average shaped British bloke into the car. Considering I regularly get into a Caterham with a full cage without a problem, I'm tending to blame the car, not me. Just like Clarkson.

So I'll give you the heads up on my own situ.

I'm pretty certain all the cars currently in the UK without a full cage, have the older roll cage which is behind the rear bulkhead. Mr Lowe's recent delivery may be the exception however. The new cars coming out now no longer use this design as the ends of the shoulder straps of the harnesses pass through the engine bay, so in the event of an engine bay fire..... Personally, I'd like to think I'd notice..... So all new cars with a roll bar as opposed to a cage, inherit the rear section of the full cage.

Now the problem. Because the seat back is essentially a flat panel with side bolsters, reclining the seat (which incidently means you have to move the seat forward) means you cannot curve your spine into the back of your seat to get a comfortable neck, if you want to sit low. Your head is tilted very much downwards to compensate. If you have a chin (or several) like mine, this means your chin is on your chest, so its even hard to talk. This is not at all comfortable.

To exacerbate things more, your skull is also now just a very short distance from the horizontal bracing of the rear cage section, which in the event of a rear end shunt is a very significant hazzard. Of course if you use cage padding it will help, but without a helmet this is still possibly going to knock you unconcious.

And you need to sit low if you ahve the full cage.

The full cage, as you are most likely aware, has a tube which runs just inside the top of the windscreen and I found that for a proper driving position unless you can get even lower still in the seat (meaning recline the back) this bar intereferes with your vision in a bad way. If you have sever sat in a Cerbera, the effect is about twice as bad as that.

Effectively, as the bar across the top of the screen is not a particularly close profile to the top of the screen, you have to set your eye level around 2" lower in the car to compensate.

This, in my opinion is the biggest flaw of the RCR, and this is a key reason I have restrained myself from placing my deposit with Fran.

Fran of course has some photos of 6'8" people who own RCR's so I am making a mountain here clearly. These people must have long legs and short torsos or some clever form of vertibrae. Either that or they are like the contortionists I used to see at the circus as a boy.

So whats the solution?

Modify the cage? The RCR cage is not legal for competition in the UK. It does not comply with RAC MSA regs. The design lacks any diagonal bracing, which is essential for good cage performance, an issue however driven by the fact that the diagonal has to miss the crank nose.

Some creative design can resolve this and fabricating your own cage is one solution, but unless you have a tube bender and a skilled hand on the MIG, its a bit of a specialist job.

So getting a Safety Devices type company to make something is one option. Probably very expensive as a very low volume option however.

I think the cage can be improved. Removing the horizontal tube behind the drivers head is an essential safety mod in my opinion. Increasing the cages weight by adding more tubes into the rear bulkhead is a downside, but that the only way to overcome the intrusion of the crank nose into the rear bulkead.

A more accurately curved tube above the screen will also permit an extra inch or so of vertical field of vision.

Alternatively we could ask Fran to provide a lowered floor, but on the UK's roads that would be a disaster, and very prone to damage on its leading edge.

The best solution however will be to redesign the seat to incorporate a curved backrest. The current upholstery does not really allow this without looking a bit of a dogs breakfast around the bolsters, so it will mean getting the covers modified, or better still convincing Fran to add a curved seat to the options inventory.

All in all I was surprised by the problems I had fitting in the car. While the footwells in the RCR are enormous, its the seating angle which has to be got right if you are going to concentrate on driving rather than neck ache.

I hasn't put me off, but it will seemingly all add to the cost. Luckily the Dollar is moving the right way again today, so all is not lost!

03-17-08, 06:46 PM	#11 (permalink)
Arnie ADW UK Rookie Join Date: May 2007 Location: UK Posts: 23 Rep Power: 2	Re: Who's got an RCR40 in the UK? Ian, I'm also looking at an RCR and have found a few helpful individuals, here in Blighty, willing to let you plant your backside in the car. I have done this and have a big problem getting my 5"11 94kgs of average shaped British bloke into the car. Considering I regularly get into a Caterham with a full cage without a problem, I'm tending to blame the car, not me. Just like Clarkson. So I'll give you the heads up on my own situ. I'm pretty certain all the cars currently in the UK without a full cage, have the older roll cage which is behind the rear bulkhead. Mr Lowe's recent delivery may be the exception however. The new cars coming out now no longer use this design as the ends of the shoulder straps of the harnesses pass through the engine bay, so in the event of an engine bay fire..... Personally, I'd like to think I'd notice..... So all new cars with a roll bar as opposed to a cage, inherit the rear section of the full cage. Now the problem. Because the seat back is essentially a flat panel with side bolsters, reclining the seat (which incidently means you have to move the seat forward) means you cannot curve your spine into the back of your seat to get a comfortable neck, if you want to sit low. Your head is tilted very much downwards to compensate. If you have a chin (or several) like mine, this means your chin is on your chest, so its even hard to talk. This is not at all comfortable. To exacerbate things more, your skull is also now just a very short distance from the horizontal bracing of the rear cage section, which in the event of a rear end shunt is a very significant hazzard. Of course if you use cage padding it will help, but without a helmet this is still possibly going to knock you unconcious. And you need to sit low if you ahve the full cage. The full cage, as you are most likely aware, has a tube which runs just inside the top of the windscreen and I found that for a proper driving position unless you can get even lower still in the seat (meaning recline the back) this bar intereferes with your vision in a bad way. If you have sever sat in a Cerbera, the effect is about twice as bad as that. Effectively, as the bar across the top of the screen is not a particularly close profile to the top of the screen, you have to set your eye level around 2" lower in the car to compensate. This, in my opinion is the biggest flaw of the RCR, and this is a key reason I have restrained myself from placing my deposit with Fran. Fran of course has some photos of 6'8" people who own RCR's so I am making a mountain here clearly. These people must have long legs and short torsos or some clever form of vertibrae. Either that or they are like the contortionists I used to see at the circus as a boy. So whats the solution? Modify the cage? The RCR cage is not legal for competition in the UK. It does not comply with RAC MSA regs. The design lacks any diagonal bracing, which is essential for good cage performance, an issue however driven by the fact that the diagonal has to miss the crank nose. Some creative design can resolve this and fabricating your own cage is one solution, but unless you have a tube bender and a skilled hand on the MIG, its a bit of a specialist job. So getting a Safety Devices type company to make something is one option. Probably very expensive as a very low volume option however. I think the cage can be improved. Removing the horizontal tube behind the drivers head is an essential safety mod in my opinion. Increasing the cages weight by adding more tubes into the rear bulkhead is a downside, but that the only way to overcome the intrusion of the crank nose into the rear bulkead. A more accurately curved tube above the screen will also permit an extra inch or so of vertical field of vision. Alternatively we could ask Fran to provide a lowered floor, but on the UK's roads that would be a disaster, and very prone to damage on its leading edge. The best solution however will be to redesign the seat to incorporate a curved backrest. The current upholstery does not really allow this without looking a bit of a dogs breakfast around the bolsters, so it will mean getting the covers modified, or better still convincing Fran to add a curved seat to the options inventory. All in all I was surprised by the problems I had fitting in the car. While the footwells in the RCR are enormous, its the seating angle which has to be got right if you are going to concentrate on driving rather than neck ache. I hasn't put me off, but it will seemingly all add to the cost. Luckily the Dollar is moving the right way again today, so all is not lost!