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MTPLM - crikey

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This is on the same CAMHC site as us at the minute. Clearly home made and unlikely to have gone through the trailer IVA process hence won’t have any weight plate. Unladen weight guesses on a postcard! I bet it’s not far off 2000kgs…..

It looks as though it’s mounted on a proprietary chassis and that would have a statutory weight plate. Maybe the wooden structure on the chassis is demountable, in which case it would be considered as payload and then the combination of chassis and what‘s on it wouldn’t be subject to an IVA. That would be a clever way of getting around the regulations that apply to factory-built caravans.
 
It looks as though it’s mounted on a proprietary chassis and that would have a statutory weight plate. Maybe the wooden structure on the chassis is demountable, in which case it would be considered as payload and then the combination of chassis and what‘s on it wouldn’t be subject to an IVA. That would be a clever way of getting around the regulations that apply to factory-built caravans.
It’s on an old caravan chassis and has no obvious weight plate. It’s creative but made entirely from 68 x 45mm timber and permanently bolted to the chassis. IVA is largely ignored by amateur car and trailer builders alike.
 
It’s on an old caravan chassis and has no obvious weight plate. It’s creative but made entirely from 68 x 45mm timber and permanently bolted to the chassis. IVA is largely ignored by amateur car and trailer builders alike.
How can you register an amateur car that hasn't been IVA'd
 
How can you register an amateur car that hasn't been IVA'd
Effectively ringing. It’s so prolific it’s almost “accepted”. Attended any hot rod show and you’ll see plenty of replicas wearing Ford Model Y and the like registrations.
 
It’s on an old caravan chassis and has no obvious weight plate. It’s creative but made entirely from 68 x 45mm timber and permanently bolted to the chassis. IVA is largely ignored by amateur car and trailer builders alike.
If an old caravan chassis no need for a weight plate however I think the axle may still be rated for a certain load and may have a plate or weight markings embedded on it?
 
If an old caravan chassis no need for a weight plate however I think the axle may still be rated for a certain load and may have a plate or weight markings embedded on it?
Yes I think you’re correct. I won’t bother crawling underneath to check though! 😂
 
The trailer it's built on will more than likely have a plate defining its maximum weight. Not too happy with that Calor cylinder just sitting there, doesn't seem to be secured in any way.

For the information of any newbies there CAN BE (and very often is) a difference between a caravans MTPLM and its maximum permitted legal weight.

For example I owned a Bailey 640 for 6 years. It's MTPLM, a figure provided by Bailey but having NO legal standing, was 1540kg (could be slightly out as I no longer have it)
The ""Statutory" VIN plate showed a maximum weight of 1500kg (I think)
Any prosecution in regards to excess weight would SOLELY rely on the numbers on the Statutory (VIN) plate.
Yes it IS a very confusing subject that is a tad difficult to get your head around.
 
The trailer it's built on will more than likely have a plate defining its maximum weight. Not too happy with that Calor cylinder just sitting there, doesn't seem to be secured in any way.

For the information of any newbies there CAN BE (and very often is) a difference between a caravans MTPLM and its maximum permitted legal weight.

For example I owned a Bailey 640 for 6 years. It's MTPLM, a figure provided by Bailey but having NO legal standing, was 1540kg (could be slightly out as I no longer have it)
The ""Statutory" VIN plate showed a maximum weight of 1500kg (I think)
Any prosecution in regards to excess weight would SOLELY rely on the numbers on the Statutory (VIN) plate.
Yes it IS a very confusing subject that is a tad difficult to get your head around.
The MTPLM upgrades makes a mockery of weights. I believe it is kept low to encourage people with lighter cars purchase the correct maximum weight for their car. Then for a few quid increase the MTPLM
 
The MTPLM upgrades makes a mockery of weights. I believe it is kept low to encourage people with lighter cars purchase the correct maximum weight for their car. Then for a few quid increase the MTPLM
That’s right as it seemed to come in when successive models of cars took out serious amounts of weight.
 
The MTPLM that the NCC calculates on the basis of MIRO plus a payload derived from a formula is the source of all confusion. It is neither a maximum nor technical, but only a figure that is conjured up for marketing purposes to make a caravan more attractive by suggesting that it has a lower MTPLM than it actually has, thereby making it possible to be towed by a car with a lower towload capacity. That is really pulling wool over the customer's eyes.
 
The MTPLM that the NCC calculates on the basis of MIRO plus a payload derived from a formula is the source of all confusion. It is neither a maximum nor technical, but only a figure that is conjured up for marketing purposes to make a caravan more attractive by suggesting that it has a lower MTPLM than it actually has, thereby making it possible to be towed by a car with a lower towload capacity. That is really pulling wool over the customer's eyes.
When we considered a Knaus the options included a number of payload upgrades so it could be tailored to a customers particular cars towing capability.
 
Why does being a member of the NCC prevent a British caravan maker doing similar. Are you saying it’s a ‘ closed shop’.

I don’t know for sure but I suspect that as an NCC member, the manufacturer is bound by the NCC principle of declaring minimum possible MTPLMs, even to the extent that it’s a calculated rather than actual value, with the object of ensuring that the largest possible market is covered. Their practice wouldn’t make sense for any other reason.
Modern production methods don’t make a selection of chassis allowing various weight upgrades any more expensive for the manufacturer because components can be delivered to him in production sequence, thus avoiding any increase in inventory and floor space, so that is no longer an argument against offering a whole range of options.
 
I don’t know for sure but I suspect that as an NCC member, the manufacturer is bound by the NCC principle of declaring minimum possible MTPLMs, even to the extent that it’s a calculated rather than actual value, with the object of ensuring that the largest possible market is covered. Their practice wouldn’t make sense for any other reason.
Modern production methods don’t make a selection of chassis allowing various weight upgrades any more expensive for the manufacturer because components can be delivered to him in production sequence, thus avoiding any increase in inventory and floor space, so that is no longer an argument against offering a whole range of options.
For context, the NCC introduced the concept of MIRO + minimum payload = MTPLM where the minimum payload is calculated based on no. of berths and internal length because some member manufacturers were providing even less payload and were therefore impractical for touring!

It has long been a total farce that "Maximum Technically Permitted Laden Mass" (MTPLM) can be upgraded without some sort of physical change occurring, eg higher rated tyres, brakes or axle(s).

At the time, the then Caravan Club was a member of NCC, as a major site operator - not to represent the interests of their members - and failed to lobby for common sense!
 
For context, the NCC introduced the concept of MIRO + minimum payload = MTPLM where the minimum payload is calculated based on no. of berths and internal length because some member manufacturers were providing even less payload and were therefore impractical for touring!

It has long been a total farce that "Maximum Technically Permitted Laden Mass" (MTPLM) can be upgraded without some sort of physical change occurring, eg higher rated tyres, brakes or axle(s).

At the time, the then Caravan Club was a member of NCC, as a major site operator - not to represent the interests of their members - and failed to lobby for common sense!
Compared to the majority of British payload upgrades which are mostly 15-35kg the Knaus range we looked at were substantially greater. You could order from a variety of payload increases some of which were so substantial that there must have been axle differences.
 
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It has long been a total farce that "Maximum Technically Permitted Laden Mass" (MTPLM) can be upgraded without some sort of physical change occurring, eg higher rated tyres, brakes or axle(s).

If an MTPLM can be upgraded without some sort of physical change it wasn’t a technically permitted maximum in the first place but an artificial value that was conjured up and called an MTPLM without being that. The actual MTPLM is always what is displayed on the statutory plate and the type approval certificate that was issued with the caravan (but seldom passed on to the customer in the UK because it’s only needed for registration purposes).
 
Compared to the majority of British payload upgrades which are mostly 15-35kg the Knaus range we looked at were substantially greater. You could order from a variety of payload increases some of which were so substantial that there must have been axle differences.
Not only Knaus offer a whole range of upgrades, but practically every Continental manufacturer. Their price lists usually state what technical changes are involved with each option - whether it’s only tyres with a higher load rating, a heavier duty axle with bigger brakes or even a complete chassis change. If I recall correctly, one manufacturer, I think it was Fendt, even included a change from a single axle to a twin axle in his list of optional weight upgrades.
One could argue that if no technical change is involved for a particular weight upgrade, then the design was overengineered for the standard MTPLM in the first place.
 

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