Uprating GVW and tyre choices

[Brian Kirby]

Karen0858 - 2017-07-26 6:48 PM

 

Hello Brian

 

The spec allows 200kg for rear garage and rear loading space. If we load the back as we would like to, we would have 2 e-bikes on rack totalling 56k, bike ramp 7.5, bike 78. I assume I should include gas bottles as the storage for them is also at rear so another 30kg. That takes the total to 173kg in round figures. You can see why we don't really want to carry the spare wheel.

 

I do wonder what they mean by "rear storage space" as we have cupboards in the back of the van plus the trauma heater is also fitted in the rear. Mus confess that I have not really considered weight of the boiler in this calculation or included clothes in cupboards.

 

Karen

I don't think you need to take account of the gas bottles or the Truma, as they should already be taken into account in calculating MIRO (though possible only one bottle). I think the contents of the cupboards would count. It is a structural limit on the rear overhang for the (unforeseeable) load you might place in the garage area and associated storage spaces.

 

But, I don't think you've said how much over its rear axle load limit your van is when loaded as you would like. What is the actual extent of the problem? It seems it can't be that much.

[Derek Uzzell]

It also might be useful to know which model of Burstner motorhome Karen owns (and its year of manufacture).

 

It is sometimes visually obvious (eg. when the motorhome model has a long rear overhang) that carrying hefty items at the vehicle’s rear is going to load up the rear axle appreciably.

[Karen0858]

Hi Derek

 

It is an IXEO IT735, 2014,

 

There is a large overhang and given the comments and advice received, have now started to explore the option of having a tow bar fitted and putting bike on trailer. We are of the age that we have C1E on our licence. That also gives us freedom to explore towing an a-frame car for winter use too.

 

Karen

[monique.hubrechtsgm]

In belgium the engineers are approved to make a new coc document if they have the certificate. And that follows the the eec type approval rules including new plates. On the fiat and burstner and that can not without theiir approval to avoid claims. You have entered an new stage in the multiple manufacturing process. Alko air suspension options are already included in their basic type approval on their chassis, That is not the case whit goldschmitt they have a national german type approval by tuv for ,most motorhomes. It is just very understandable how it works.

[Keithl]

But Monique, the rules are VERY different in the UK to most of mainland Europe, we do not have to bother with re-certification and new CoC's for a lot of changes!

 

One of the joys of living on this island of ours :D

 

Keith.

[monique.hubrechtsgm]

These inflation kits is a nightmare. Have a good road assist who can vulcanise whit plugs. An alternative would be that you carry your jacks and now the right jacking points of your vehilcle and have a inflated spare tyre wheel of the correct dimensions and firmily placed. Together again weight to carry weight for years if not flat. that is called the dilemma.

[Derek Uzzell]

Karen0858 - 2017-07-27 4:28 PM

 

Hi Derek

 

It is an IXEO IT735, 2014,

 

There is a large overhang and given the comments and advice received, have now started to explore the option of having a tow bar fitted and putting bike on trailer. We are of the age that we have C1E on our licence. That also gives us freedom to explore towing an a-frame car for winter use too.

 

Karen

 

Towing seems like the wisest option to me.

 

This link

 

http://www.southdownsmotorcaravans.co.uk/galleries/2014-burstner/ixeo-it735/pixindex.html

 

has photos of a 2014 Burstner Ixeo it735 and it’s evident from the 5th photo (poor quality copy attached) how long the rear overhang is and, consequently, how carrying heavy stuff in the garage and more heavy stuff on a rear-mounted rack would add to the vehicle’s rear-axle loading.

 

If you think you might tow a small car at some stage, you might want to consider obtaining a trailer large enough to carry a car and carry the motorbike on it, rather than have a trailer suitable only for the bike and tow the car on an A-frame. I can fully appreciate the negatives of having one (largish) trailer - it’s just a thought...

[Brian Kirby]

I'm inclined to agree with Derek, but with some reservations.

 

First is the self-weight of the tow bracket which, with so pronounced a rear overhang, I suspect may be substantial.

 

Second is the necessary down-force that must be applied to the tow hitch in the interests of trailer stability. Probably not that great for the motorbike trailer, but significant for a car unless flat towed on an A frame.

 

The motorbike was quoted at 78kg, and would be carried inboard. The trailer hitch, of necessity, will be outboard, so even further behind the rear axle, thus multiplying the rear axle load and reducing the front (traction) axle load. You'll need to think in terms of 7% of the combined weight of the trailer plus car (or bike) falling onto the hitch.

 

Car plus trailer will be in the region of 1 tonne, so the minimum downforce for stability would be about 70kg, and it is acting further back than the bike. I think, in practical terms, that means you will have no advantage over carrying the bike, and would possibly be worse off, plus you'd have no allowance for the self-weight of the tow bracket. If you needed the enhanced rear axle loading for the bike I think you'll also need it for a car plus trailer.

 

I also suspect that with a rear overhang that is so long relative to wheelbase, towing a car on a trailer would result in your van's handling being degraded, with increased sensitivity to tramlining, plus traction difficulties on hills, especially in the wet. In short, the feeling that the tail is perpetually wagging the dog! The best recipe for stable towing is a short rear overhang, long overhangs tend to sway over irregularities in the road, inducing sway in the trailer. The bike plus trailer might prove OK, although it will be a short trailer towed by a relatively long vehicle, which is not the best combination.

 

My honest opinion is that you might be better advised to save your money, and put it towards changing your motorhome to one that better accommodates what you want to do. It would be a shame to go down a costly path that eventually proves unsatisfactory, and then decide the only remedy is to change the van. I suspect that you might then find your modifications resulted in a reduced trade-in value, in part due to the MAM being over 3.5 tonnes. Money and drain? The alternative to that, I guess, is to trim your ambitions to what your present van can accommodate without radical measures. Sorry, but from my perspective, you have a fundamental mis-match between your vehicle and your present ambitions.

[Derek Uzzell]

The simplest solution would be to not carry Karen’s husband’s beloved motorbike. This would save 87.5 kg (bike + ramp), the two e-bikes could then be carried within the rear garage and (presumably) uprating the Burstner’s rear axle’s maximum loading from 2000kg to 2240kg would no longer be necessary.

 

Everything that Brian has said is correct and, although following SVTech’s advice should allow the motorbike and e-bikes to be carried legally as far as UK regulations are concerned, Fiat, nor Burstner, nor Michelin (nor any other tyre manufacturer) will ‘authorise’ altering the motorhome’s original rear tyre-size or adding air-assist to the rear suspension. An insurer would probably be happy enough with the changes and I don’t think the DVLA would need to be notified. A revised data-plate (or sticker) would be required to show the 2240kg datum, but SVTech could handle that.

 

If the thought of taking the SVTech approach without ‘official’ authorisation and approval from Fiat/Burstner/Michelin is going to cause nightmares, don’t carry the motorbike.

[Karen0858]

Certainly a minefield.

 

We love the van, it has a great spec but we just didn't understand the payload advection when we purchased, it is our first one.

 

Thanks for all the advice, maybe a different van is the answer.

 

Karen

 

 

 

 

[Brian Kirby]

Derek's post prompted me to look again at Karen's OP. The existing MAM is, of course, 3850kg, which seems wrong. The standard MAM for both 2013 and 2014 model year Ixeo IT735 models was 3,500kg, at which weight they had an MIRO of 3070kg in basic trim (i.e. no options, 130hp manual), with a payload of 430kg (very tight, IMO, for a 7.5M long van).

 

The optional alternative chassis was 4,000kg, not 3,850, so the 3,850 seems to have been achieved by an earlier re-plating exercise. Unfortunately, this illustrates the shortcoming of re-plating exercises where the full axle loads are added together to achieve a higher MAM (i.e. front axle limit of 1,850 plus rear axle limit of 2,000kg = 3,850kg). It is not possible to achieve the increased 3,850kg MAM without one, or other, of axles becoming overloaded, as karen is discovering, so the re-plate is an illusion in real-world terms.

 

It would be interesting to know whether Karen and her husband acquired this van at 3,850kg, or whether they had it re-plated because they found the original MAM insufficient, and whether whoever did this pointed out that it is practically unachievable.

[Karen0858]

We bought it second hand from a dealer.

 

It was already plated at 3,850 and we were not given any information or advice regarding payload. We did say we were intending to buy a small motorbike to fit in the garage and chose this van because the mini bike we were considering would fit. The dealer did not give us any feedback on that nor give us any advice on whether it would be within weight allowances. We have found out the hard way.

 

Karen

[Derek Uzzell]

Brian Kirby - 2017-07-28 3:39 PM

 

Derek's post prompted me to look again at Karen's OP. The existing MAM is, of course, 3850kg, which seems wrong. The standard MAM for both 2013 and 2014 model year Ixeo IT735 models was 3,500kg, at which weight they had an MIRO of 3070kg in basic trim (i.e. no options, 130hp manual), with a payload of 430kg (very tight, IMO, for a 7.5M long van)...

 

 

The following link suggests that a 2014 Burstner Ixeo it735 was marketed with a MAM of 3500Kg, 3650Kg, 3850Kg or 4000Kg (or even 4250kg).

 

http://www.southdownsmotorhomecentre.co.uk/new-2014-burstner-ixeo-it735-fiat-ducato-motorhome.html

 

This advert also mentions the 3850kg figure

 

http://www.becksmotorhomes.com/vehicle/2014-burstner-ixeo-it735

 

If the 3850kg plate on Karen’s motorhome is a Burstner one, it’s probably the original one and the vehicle has not been ‘up-plated’.

 

Burstner have a habit of ’stretching’ the MAM of Ducato ‘light’-based models and although having a MAM that equates to the total of the front and rear axle maximum loadings may seem odd (and undesirable), that’s the reality.

 

 

 

[Brian Kirby]

How odd! My source was this: http://tinyurl.com/y7uf5zpr

 

Yes, I'd spotted the Becks one, and when I saw the tech brochure on Southdowns' website assumed it, too, must have been plated up.

 

The 2013 model year Burstner technical brochure (in case Karen's is that year but first registered in 2014) is also downloadable from Southdowns. Neither indicates MAMs other than 3,500kg and 4,000kg, both of which would preserve reasonable loading flexibility. It seems odd that the Burstner literature doesn't mention them, when Southdown's say they were available.

 

3,650kg gives reduced, though probably workable, flexibility, but 3,850kg on so large a van, with so long a rear overhang, really should have carried a health warning! Possibly the original owner also discovered this, and decided to sell.

[Derek Uzzell]

The Becks Motorhomes-related link in my last posting mentioned that the Burstner it735 being advertised in 2014 had a "Weight Upgrade To 3850Kg” and, as the vehicle was new, it would have been reasonable to assume that this upgrade was an ‘official’ Burstner option, not fitted by Becks.

 

However, the clincher that a 3850kg weight was optionally available is in this Camping-Car Magazine review of a 2013 Collection it735

 

http://www.camping-car.com/essais/liste-essais/essai-camping-car-profile-burstner-ixeo-it-735

 

In the paragraph beginning "Notez que, comme tous les modèles de sa catégorie, avec lit central...” the 3500kg PTAC is mentioned, adding "If you have the appropriate permit, it is possible, as an option (495 €), to raise the PTAC to 3850 kg.”

 

There’s an on-line ProMobil review of a 2011 Burstner it735 stating that its MAM was 3650kg and there’s some on-line indication that the 3850kg option mentioned by Camping-Car Magazine MIGHT have involved Goldschmidt springs.

 

But as long as Karen’s motorhome is correctly plated to 3850kg (and presumably is registered in the Private HGV vehicle tax class) it doesn’t really matter what Burstner’s 2013/2014 documentation said as she did not buy the vehicle new.

 

There’s a 2013 Burstner motorhome instruction manual viewable on-line. The document is very comprehensive and there’s a good deal of guidance about payload and how to calculate the effect of adding load behind the rear axle. Unfortunately such advice will be of little value to a buyer of a Burstner model who has no motorcaravanning experience.

 

Although Karen is critical of the dealer that sold them the motorhome, (as I understand it) it’s not carrying the mini-bike that’s the problem, it’s carrying the mini-bike and two e-bikes as well.

 

Me, I’d check with my insurer about the tyre-size change and air-bellows additions and, if the insurer were comfortable with those modifications, I’d put a pair of Michelin “Agilis Camping” 225/70 R15CP tyres on the rear axle, ditch the spare wheel and have tyre sealant put in the four remaining tyres, fit air-bellows to the rear axle and carry the mini-bike in the garage and the two e-bikes on a rear carrier. And once I’d done that I would not agonise about it. ;-)

[Karen0858]

Can I just say how much I appreciate all the research that you and Keith have been doing.

 

Yes, the van is fitted with Goldschmitt springs and we believe that it I should these that resulted in the van being first registered at 3,850. The original dealer was Becks ( though we bought it from a second dealer who was probably not aware of its history)

 

We have been agonising, nearly got to the point of throwing in the towel completely, especially when following advice on the tow bar option, it became apparent that this was not an alternative solution for the motor bike.

 

So, after much debate, we arrived at the same conclusion you have Derek. Will ring the insurers and if no concerns on their part, will proceed with the original plan of uprating the rear axle with tyres and suspension. Will see what payload we get and you never know, might just keep the spare wheel!

 

Now, what does everyone think about a heliport on the roof? (lol)

 

Thanks again for all your input, I never expected to receive so much feedback from the forum. Am so glad I posted.

 

Happy motor Caravaning one and all.

 

Karen

[webby1]

We uprated with Svtech to 3850 and with air suspension and 112 tyres we were able to increase the rear axle weight. It is as bad to be overloaded on one axle as it is to be overloaded in total

 

Eventually we replaced all 4 tyres with Toyo H09 225 rated as 112.These are also MS rated and have been fine. I cannot see the differences some people detect with hard rides, soft rides camper tyres etc.........as long as they are in good condition.

 

Svtech were also in agreement ,that when we changed to the new tyres and sent a photo or receipt they would issue a new sticker with the new rear loading.

 

We do not carry a spare and figure we can get a new tyre delivered to most places in a few days and luckily we have a motorhome to stay in while we wait. IF we ever get a puncture.