Scooter Rack for an Amethyst

[dleah55]

Has anyone any experience of putting a scooter rack onto an Autosleeper Amethyst. Is it better to use a towbar rack or one fitted onto the van?

[Mel E]

Can't help with which is best for your 'van, but do check the axle loadings before comitting. A solid rack plus scooter hanging that far back can easily overload the rear axle and, worse, lighten the front axle by the same amount affecting traction, steering and braking. As well as being illegal, it puts your insurance cover at risk.

[Derek Uzzell]

Agree with Mel about loading limits. Auto-Sleepers have used the Amethyst name at least twice and (because of the heavy monocoque body) useful payload was certainly marginal on the 1990s version with 3300kg Transit chassis. The current version with 3500kg chassis may have more payload, though I'm VERY wary of the 602kg figure given in the MMM Buyers' Guide listing.

[dleah55]

thnaks Derek - but to a newcomer what does that all mean. My Amethyst is 1996

[Derek Uzzell]

It means that it would be a sensible plan for you to weigh your motorhome in fully loaded state (overall and axle weights) before committing to hang a scooter off the back.

[fjmike]

The one thing to watch out for as well as what has been mentioned before is the amount of overhang (distance between rear wheels and back of motorhome). If this is too great you will find that you no longer have accurate steering :-S

[Yorkshire Tyke]

Hi what they mean about the overhang and increased weights is a branch of mechanics called "Moments of Force" Take two mwasurements 1) from the rear wheels to where the center of your scooter rack would be, Call that (CR) ft 2) betweent the wheel axles, wheelbase (WB)ft determine the weight of the scooter (WS)lb Now Calculations Added weight to rear axle = CR x WS Weight reduction front wheels = {WB + CR} x WS Now weigh the van unladen and fully loaded weighing front and rear axles seperately in your hand book will be some values for the MAXIMUM weight to be placed on each axle If you add the weight when full on Rear to the added weight rear axle this should not exceed the max allowed weight for that axle If it does fit a tow ball & use a trailer If not Now subtract the front axle added weight from the weight when empty this will give you a figure which is the weight over the front wheel should you drive the van empty In other words how much traction you have left to steer the van But I DO NOT KNOW how much this can be reduced for safety Perhaps someone else can come up with figures I only used these for working out stresses in overhaed wires and beams

[Derek Uzzell]

David:

A follow-up to my over-hurried reply to your last posting...

Newcomers to motorcaravanning often don't appreciate how restricted some motorhomes' useful payload is. Your 'van is heavily constructed and quite large but uses a chassis with a relatively low maximum overall weight limit. I dug out a 1996 copy of Which Motorcaravan that gave the payload of an Amethyst GX as 349kg. This may sound plenty, but the figure won't include any allowance for fresh water, gas bottles, passengers, luggage, weighty options (eg. an overcab bed instead of cupboards) or heavy accessories (eg. an awning or roof air-con). History has also revealed that the payload of full-production motorhomes can vary significantly from that of pre-production prototypes. This all means that the only sure way of confirming how much spare payload a particular motorhome has is to load it up and put it on to a weighbridge.

If you use your Amethst to transport a scooter on a rear-mounted rack, then the overall weight of your motorhome will rise by the combined weight of the scooter and rack, while a proportionately higher load (due to leverage) will be placed on the rear axle. I've some concern that, when loaded 'normally', your motorhome may not have enough payload left for you to carry a scooter and remain within the vehicle's permitted load maxima. My doubts may be unfounded, but the only way for you to find out would be to get your 'van's weight checked.

My previous motorhome was a 1996 Herald Templar built on a similar specification Ford Transit chassis to your Amethyst's, but with a smaller body and using lighter construction techniques. I once wrote a piece for the Herald club magazine about how easily a motorhome could be overloaded inadvertently and I've copied the text below.

Regarding your original question, I don't really understand the difference between the two types of rack you mention. Because of the weight of a scooter I've always assumed that any carrying platform would need to be very substantially made and directly attached to the motorhome's chassis. If you were considering attaching the rack to the 'van's rear bodywork (like a bicycle rack), then I would definitely rate that a bad idea.

Here's the Herald magazine article...

Weighing Up Your Options.

This is a cautionary tale about payload or, more accurately, the lack of it.

Our dearly-departed 1996 Templar Hallmark II was constructed on a Transit 150 long-wheelbase chassis, as (to the best of my knowledge) were all 'classic' Ford-based coachbuilt Heralds. This chassis has a maximum authorised overall weight of 3300kg and maximum axle weight-limits of 1600kg (front axle) and 2000kg (rear axle).

When we bought the Herald in 1998 we were new to the game and, although I understood payload was important, finding out exactly how much was available did not rank high on my priority-list. I had obtained a copy of a Templar test report, glanced at the quoted payload figure and thought "That's bound to be enough". Of course, after purchase, a motorhome rapidly piles on the pounds as its proud owner adds 'essential' clobber that will never be removed until the vehicle changes hands. Basically, if you don't weigh a motorhome as soon as you get it, the chances are small of discovering subsequently its genuine empty weight.

As we always travelled light (or so I believed) - no barbecues, bikes, etc. - I'd assumed our Herald's payload was plentiful and I never bothered to put the 'van on a weigh-bridge. That was until our September 2004 visit to Brittany when we spotted a sign for a "pont bascule" that was "automatique" and, even more attractive, "gratuit". ("Free" is an important word in my dictionary.)

This weigh-bridge was a biggie, in the back of beyond by a cement works (closed that Saturday). Having parked the Herald on the weighing-platform, I entered the little booth alongside and tried to decipher how to get the thing to work. A key-code seemed to be needed and, apparently, there was a charge for the service, oddly in old-currency francs not euros. After some hopeless button-pressing and equally futile cursing by me, my wife Ruth enquired "Does this mean anything?" pointing to an inconspicuous (Well, I reckon it was inconspicuous!) digital display showing the number 3080. "Try getting into the 'van", I said and, when the read-out rose by 60 (which was near enough as an accuracy check) I knew we were in business. I then took individual axle-loadings, which were 1380kg (front) and 1700kg (rear).

Load-wise the state of play at the time was this. We had just left the aire de services at nearby La Roche-Derrien, so the Templar's fresh-water and toilet-rinse reservoirs were brim full and the waste-water tank and toilet-cassette were both empty. Our gas bottles (a 6kg Calor and 5kg MTH Autogas refillable) were both full and the vehicle's fuel tank was about 25% full. Because we were approaching the end of our holiday, the near-side seat-locker was crammed with boxes of wine, though the centre section of the opposite locker remained empty, awaiting a second helping of plonk to be stowed there just before we left France. Otherwise, nothing unusual onboard that two people spending a Summer fortnight touring wouldn't take with them.

OK, a weight of 3080kg and a limit of 3300kg leaves 220kg to play with. But, together, Ruth and I weigh 125kg and to that figure about 35kg can be added to top up the fuel tank. That leaves just 60kg, not much more than the weight of the extra wine I shoehorned in later. When I drove the Templar on to the ferry, its overall weight must have been pretty close to its authorised maximum.

The Templar II is the smallest and lightest of the Herald bunch comprising Aragon, Insignia, Templar and Valencia. Our 'van's Atwood heater had been replaced by a Truma equivalent, but both appliances weigh much the same. The only alteration to its basic ex-factory specification that would have added notable weight was my fitting of a larger capacity (and 18kg heavier) waste-water tank. However, that gain would have been offset by the Compass factory having 'forgotten' to fit the substantial rear corner-steadies that were part of the standard 1996 spec and my use of a lightweight gas-bottle. Our Herald had no hefty optional extras common to motorhomes: no tow-bar, no awning, no top-box, no extra batteries, no big steel gas-tank - you name it, it didn't have it.

Now, if our options-free 2-person Templar could, apparently, approach its maximum authorised weight quite easily, what about Templars festooned with options? And where does this leave the longer (and, logically, heavier to begin with) Herald designs, particularly those with living-area passenger-carrying capability? Other Herald-owning Club members may wish to ponder over these 3300kg questions.

[dleah55]

thank you very much for your article. I found it very interesting. Have now decided to use a towbar instead and put the scooter on a trailer :-D