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Broadway Tyre Pressures!

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Post by Tigerfish Sat Apr 03, 2021 4:10 pm

Hello,
I am a somewhat wrinkly ex caravaner now a proud MH owner, a 2016 Broadway EK with less that 5,000 miles on the clock.  She's been sleeping in a nice warm barn since the 1st December and SORN, but now is the time to wake her up.  Vehicle battery is dead, but I am dealing with that. I am more concerned about getting the correct tyre pressures set, and cannot seem to establish the correct settings.  There is a plate I know in the drivers door frame but that is in bars and this old bunny works in PSI, and anyway I suspect that the Peugeot plate refers to the base vehicle not the Autosleeper conversion. I can't find any reference to tyre pressures in the AS handbook.
So any advice on front and rear tyre pressures would be appreciated.

TF
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Post by Tinwheeler Sat Apr 03, 2021 4:14 pm

Google is your friend, TF. If you type "PSI to Bar conversion" in the search box, you’ll get a conversion tool.
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Post by Tigerfish Sat Apr 03, 2021 4:20 pm

Thanks TW, Any comment re my concern whether the plate refers to the basic vehicle or the AS Conversion to a MH?

TF
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Post by Tinwheeler Sat Apr 03, 2021 4:33 pm

I can’t be certain but it's probable the plate on the door pillar is the one to follow. However, I'm not familiar with your model of MH.

Logically, a MH is a base vehicle almost fully loaded and it'll be at or near the MGW of the Peugeot most of the time. To me, that says the base vehicle pressures should apply but others might know better than I.
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Post by Caraman Sat Apr 03, 2021 6:31 pm

I suspect you will have Peugeot's TPMS which is likely to be adjusted to trigger around the Peugeot fully loaded pressures shown on the tyre pressure label on the passenger door pillar which is likely to be 5.0 bar front and 5.5 bar rear for the motorhome's CP tyres.  You should check this.  The rear axle of your fully loaded Broadway is likely to be close to its rear axle's MTPLM of 2000 kg and therefore each tyre's maximum permitted load of 1030 kg, noting that loading across the rear axle will not be equal and it is dangerous for a tyre to have insufficient air pressure for its load.  This being so, you won't go far wrong setting your rear CP tyres at their maximum permitted pressure of 5.5 bar which is the pressure recommended by the ETRTO and tyre manufacturers for a rear CP tyre at its maximum load of 1030 kg.  The ETRTO somewhat controversially recommend 5.5 bar for all single fitment rear CP tyres for all rear axle masses.  The real issue will be your front CP tyre pressures because even when fully loaded, your Broadway's front axle mass will be nowhere near its MTPLM of 1850 kg.  This is something you will need to measure on a weigh bridge.  Once you have this mass you won't go far wrong inputting it into TyreSafe's on-line calculator:

[You must be registered and logged in to see this link.]

which will give you your front tyre pressure.  It will be something like 3.4 bar.  If your TPMS has not been adjusted to trigger around this pressure, you will need to get Peugeot or a back street garage to adjust it for you.  This is covered in this fact sheet:

[You must be registered and logged in to see this link.]


Last edited by Caraman on Sat Apr 03, 2021 6:33 pm; edited 1 time in total (Reason for editing : added rear)
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Post by Tigerfish Sat Apr 03, 2021 8:45 pm

All a foreign language to me!  I work in PSI, feet and Inches and Lbs and Oz’s

TF
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Post by Tinwheeler Sat Apr 03, 2021 8:57 pm

That's a very comprehensive reply from Caraman, TF. 

Just convert the figures.
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Post by Tigerfish Sat Apr 03, 2021 10:37 pm

Thanks  Caraman And TF, I will try to Google it as TW suggested. But I still prefer proper Imperial measurements.  I don’t do Metric!

TF
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Post by Paulmold Sat Apr 03, 2021 10:40 pm

Tigerfish wrote:Thanks  Caraman And TF, I will try to Google it as TW suggested. But I still prefer proper Imperial measurements.  I don’t do Metric!

TF
I'm sure you buy your fuel by the litre.

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Post by Tigerfish Sat Apr 03, 2021 10:48 pm

I think in Gallons - always divide those daft Litre things by 4.55. Anyway I just fill it up and pay the tab.
Seriously I don’t like Metric - This is the U.K.
But I drive a German car and a French ( Peugeot) based MH, mainly because I have little choice in the matter. I guess preferring  British is not fashionable these days.

TF
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Post by Caraman Sat Apr 03, 2021 10:49 pm

Tigerfish wrote:All a foreign language to me!  I work in PSI, feet and Inches and Lbs and Oz’s

TF
If you really wanted to work in psi the axle masses and maximum loads that they relate to should be in lbs and ozs rather than kg which thank goodness they are not.  The definitive figures are given in bar.  For an approximate conversion to psi, multiply the pressure in bar by 14.5037738 so for example, 5.5 bar approximates to 79.7707558 psi, 5.0 bar approximates to 72.5188689 psi and 3.4 bar approximates to 49.3128309 psi.  Its easier to Google the conversion but better still work in bar. It's never too late to change.  smile!
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Post by Tinwheeler Sat Apr 03, 2021 11:59 pm

Tigerfish wrote:I think in Gallons - always divide those daft Litre things by 4.55. Anyway I just fill it up and pay the tab.
Seriously I don’t like Metric - This is the U.K.
But I drive a German car and a French ( Peugeot) based MH, mainly because I have little choice in the matter. I guess preferring  British is not fashionable these days.

TF
Do you still use £ s d, TF?  

It's nothing to do with being British but metric weights and measures is a much simpler and logical method of working. Unfortunately, you're making life difficult for yourself by not accepting that.
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Post by Caraman Sun Apr 04, 2021 7:02 am

I think centigrade and measure in litres and meters but oddly I cling on to miles, mph and mpg.  I use psi and bar but increasingly the latter.  I show below a table I have prepared for my tyres, which are probably the same tyres that Tigerfish has, but it is in bar not psi.  Although the TyreSafe on-line calculator works in bar and kg, it converts to psi for those who can only use psi.

 
CONTINENTAL VANCO CAMPER 215/70 R15 109R CP TYRE
Front Axle Mass (kg)
Cold Tyre Pressure (bar)
Rear Axle Mass (kg)
 Baseline
Adjusted
Adjusted    
Baseline
  
5.5 max
1873 to 2060
2060 max
  
5.4
1843
2027
  
5.3
1812
1993
  
5.25
1805
1985
  
5.2
1797
1977
  
5.1
1767
1944
 2145
1950
5.0
1736
1910
 2107
1915
4.9
1705
1875
 2069
1881
4.8
1672
1839
 2060 max
1873
4.75
1664
1830
 2051
1865
4.7
1656
1822
 2013
1830
4.6
1626
1789
 1975
1795
4.5
1595
1755
 1935
1759
4.4
1564
1720
 1895
1723
4.3
1531
1684
 1885
1714
4.25
1523
1675
 1875
1705
4.2
1515
1666
 1835
1668
4.1
1483
1631
 1795
1632
4.0
1450
1595
 1755
1595
3.9
1418
1560
 1715
1559
3.8
1386
1525
 1705
1550
3.75
1378
1516
 1695
1541
3.7
1370
1507
 1655
1505
3.6
1337
1471
 1615
1468
3.5
1305
1435
 1573
1430
3.4
1270
1397
 1531
1392
3.3
1235
1359
 1520
1382
3.25
1227
1350
 1509
1372
3.2
1219
1341
 1467
1334
3.1
1187
1306
 1425 & below
1295 & below
3.0 min
1155 & below
1270 & below
 
The baseline axle masses are taken from Continental’s 2019/20 [You must be registered and logged in to see this link.], the non-bold extrapolated from the bold.  [You must be registered and logged in to see this link.] recommend using the pressure for an axle mass that is 10% higher which is reflected in the adjusted axle masses.  This is to compensate for uneven loading across the axle and any increase in axle mass since it was measured on a weighbridge, it being safer for a tyre to be slightly overinflated for its load than underinflated.  Adding load or moving it fore or aft will increase one or both of the axle masses and removing it altogether if it is behind the rear axle will increase the front axle mass.
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Post by Paulmold Sun Apr 04, 2021 8:36 am

I know  one place where pints are still the order of the day, the pub, if we ever get to go to one again.

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Post by BornAgain Sun Apr 04, 2021 8:52 am

This topic has been covered extensively in this forum but as I also have a 2016 Broadway I will add a couple of comments. You should take your vehicle to a Weighbridge when fully loaded to get the front and rear axle weights but for information, my weights with driver, passenger, 100% water, 25% waste and full fuel were 1500 kg front, 1940 kg rear for which the Continental recommended tyre pressures after adding a small safety margin are 47 psi (3.25 bar) front, 76 psi (5.25 bar) rear. Reducing the front pressures to these figures resulted in a massive improvement in ride quality, unfortunately the pressure warning light stays on and my local dealer was unable to fix this despite having all the right Peugeot software.
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Post by Tigerfish Sun Apr 04, 2021 10:05 am

Thanks everyone, that was quite amusing and I did find some very helpful advice in there. I am actually not quite the dinosaur that I might have portrayed and I am indeed quite happy working with Litres and centigrade and indeed Kilometres when driving in France and Germany. 
But I do still check on my vehicles MPG and not KPL and tyre pressures I suppose for me will always be in PSI - I guess its an age thing.

But one thing has come out of this exchange  that does concern me a little and that is the complexity of the tyre pressures question.  With the Pandemic, still around there must be literally thousands of new Motorhome owners on the road. I wonder how many of them will be assiduously checking their axle weights and their tyre pressures whether it be in Bars or PSI. Not that many I suspect!

TF
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Post by Caraman Mon Apr 05, 2021 7:34 am

Tigerfish wrote:I wonder how many of them will be assiduously checking their axle weights and their tyre pressures whether it be in Bars or PSI. Not that many I suspect!

TF
I couldn't agree more.  Like you I am an ex-caravaner.  I never took my caravan to a weigh bridge because I always knew how much load I was adding to it and I made sure it did not exceed the caravan's loading margin.  For safety I set the tyre pressures for the caravan's MTPLM.  It never occurred to me that I should take my Nuevo to a weigh bridge because as with the caravan I knew how much load I was adding and I was confident I wasn't exceeding any of the van's MTPLMs.  As for tyre pressures, I used the ones on the passenger door tyre pressure label which were the pressures on delivery from Marquis/A-S.  It was only through this Forum and subsequent investigations that I realised my front tyres were grossly overinflated at 5.0 bar and that I needed to measure the actual front axle mass on a weigh bridge to determine their correct pressures, which in my case is about 3.2 bar but could be as low as 3.0 bar.  My low profile Nuevo has the largest loading margin of all A-S's coachbuilts and you would be hard pressed to exceed its rear ale MPTLM of 2000 kg even with bikes on the back and a full water tank but I suggest this is not always the case with other coachbuilts which is why their overall mass and both axle masses should be measured on a weigh bridge when the van is fully loaded.
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Post by inspiredron Mon Apr 05, 2021 9:16 am

BornAgain wrote:This topic has been covered extensively in this forum but as I also have a 2016 Broadway I will add a couple of comments. You should take your vehicle to a Weighbridge when fully loaded to get the front and rear axle weights but for information, my weights with driver, passenger, 100% water, 25% waste and full fuel were 1500 kg front, 1940 kg rear for which the Continental recommended tyre pressures after adding a small safety margin are 47 psi (3.25 bar) front, 76 psi (5.25 bar) rear. Reducing the front pressures to these figures resulted in a massive improvement in ride quality, unfortunately the pressure warning light stays on and my local dealer was unable to fix this despite having all the right Peugeot software.
I hope that your weights are fully laden with full fridge etc. The rear axle weight is only 60kg below the 2000kg limit for that axle! And with 1500kg on the front your total is only 60kg below the 3500 overall max. That 50kg is equivalent to 3 dozen bottles of wine which is worth bearing in mind when you are tempted to fill the lockers in Spain or France  scratch head
8ncidentally, are Nuevos now plated at 3500 or still at 3300 for the EK?  When I bought mine new I asked for 3500kg with payload in mind.

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Post by marconi Mon Apr 05, 2021 9:44 am

inspiredron wrote:

I hope that your weights are fully laden with full fridge etc. The rear axle weight is only 60kg below the 2000kg limit for that axle! And with 1500kg on the front your total is only 60kg below the 3500 overall max. That 50kg is equivalent to 3 dozen bottles of wine which is worth bearing in mind when you are tempted to fill the lockers in Spain or France  scratch head
8ncidentally, are Nuevos now plated at 3500 or still at 3300 for the EK?  When I bought mine new I asked for 3500kg with payload in mind.
They are 3500 or to be accurate were in 2019.

Oddly Marquis tried to push another own name 'van, very similar, slightly down on quality of woodwork etc. "but a fair bit cheaper Sir" must have been something in it for the Salesman.

He had absolutely no idea about axle loadings and was surprised when I noticed in the Brochure that it was 3200 or 3300 and so rejected the idea.
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Post by gassygassy Mon Apr 05, 2021 1:51 pm

I believe that the Police investigate vehicles after a (EDIT: involving serious injury) crash. Not for your serveral-times-a-day BMW crashes. They of course check tyre pressures. Does anyone have any experience or knowledge of what they regard as the 'wrong' tyre pressures? Obviously a motorhome tyre with 15psi might be considered as contributory to the accident, but would tyres set at the pressures on the door frame label be considered wrong? They could hardly hoist the wreckage out of the ditch, and chuck all the bits and pieces on to a weighbridge to check if the 56 or 72psi tyres matched the weight could they?
Does anyone have experience of being diverted on to a weighbridge and having their tyre pressures measured and compared with the weight?
These are genuine questions, I am not trying to be difficult.
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Post by marconi Mon Apr 05, 2021 3:04 pm

I have seen the News footage of special checks for overloading of Caravans and Motorhomes diverted from the busy roads at peak holiday times to MOT checkpoints. You see this on French TV News also.

More personally in France I arrived at an Aire at the entrance to a Campsite to Fill and Empty on a Friday at dusk on one of their notoriously busy weekends. A big plain grey Coach loaded with Gendarmes pulled up and blocked my exit. A heavy Truck in the same grey livery then pulled into the parking area at the entrance the back dropped down to reveal a workshop everyone arriving was stopped and their papers checked.

Some cars were let through into the site old bangers were directed to the Mobile Workshop, Caravans and Motorhomes were sent round the car park and escorted in convoys to the Testing Station Weighbridge on the edge of town.

I vividly remember a French lady with a Caravan in tears signaling to me to not get involved as she was lead round her car and van by officers and then sent off in the convoy.

When I had filled up with water I started my van, the Police Coach driver signaled to say he would get in and pull forward to let me out, my wife was already out ready to see me back, "no no its OK we are not going to the Campsite we will reverse out, don't trouble yourself" we were out and off in the opposite direction. smile!
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Post by brianmor Mon Apr 05, 2021 3:49 pm

I installed new Continental Vanco tyres on my 2014 Broadway EK last week and spoke to their technical guy who replied as follows

" Based on the 215/70 R15 CP 109R Vanco Camper and providing that the weights given are the maximum axle weight you will be subjecting the tyre to; the inflation pressure guidance is:

Front: 3.5 bar (50.7 psi)

Rear (Single fitment): 5.0 bar (72.5 psi)


I have also attached the page from the technical data book showing the various pressures at various weights fyi.

I have highlighted the info you should refer to in yellow and then look at the top of the page for the inflation pressure in bar.

There are some variations in pressures given from different sources. The reason for the confusion and higher pressure from some sources on the rear is because the ETRTO (European Tyre & Rim Technical Organisation) in their standards manual have a paragraph that suggests all CP type tyres fitted as single fitment rear tyres on a camper should be inflated to a minimum of 5.5 bar (79 psi), even if the load on the axle is such that the inflation requirement based on the standard ETRTO tables and manufacturer data is lower. This advice is because of the likelihood of overloading or uneven load distribution in camper applications and the need to compensate for this with a higher inflation pressure.

Our current stance remains unchanged when calculating recommended pressures which is directly calculated from the given loads provided by yourself against the pressure recommendations in the technical data book and this is the information we provide.

However, given the information in the ETRTO manual we give this pressure as a guide and should only be used on the understanding that no single tyre will be overloaded, and the axle loads given will not be exceeded."

I weighed my van last year fully loaded on our way to a week away and was suprised when both axles were slightly underloaded. The table of pressures he sent me was the same as the previous member




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Post by Caraman Mon Apr 05, 2021 4:03 pm

gassygassy wrote:I believe that the Police investigate vehicles after a (EDIT: involving serious injury) crash. Not for your serveral-times-a-day BMW crashes. They of course check tyre pressures. Does anyone have any experience or knowledge of what they regard as the 'wrong' tyre pressures? Obviously a motorhome tyre with 15psi might be considered as contributory to the accident, but would tyres set at the pressures on the door frame label be considered wrong? They could hardly hoist the wreckage out of the ditch, and chuck all the bits and pieces on to a weighbridge to check if the 56 or 72psi tyres matched the weight could they?
Does anyone have experience of being diverted on to a weighbridge and having their tyre pressures measured and compared with the weight?
These are genuine questions, I am not trying to be difficult.
Hi - thankfully I don't have any experience of such accidents or even being diverted onto a weigh bridge to have my tyre pressures measured.  However, in May last year the NCC gave me the following advice which was not disputed by any of the many agencies I contacted on this matter (VCA, DVSA, Vehicle Safety Branch, A-S, CAMC, Peugeot, Continental, TyreSafe, MMM and others I have forgotten about!):

“All vehicles are plated with the tyre pressure for the maximum load that the vehicle can carry and it will be the drivers’ responsibility to vary this pressure if they wish to use the vehicle in an unloaded condition."
 
The Peugeot tyre pressure label clearly shows pressures for when both axles are loaded to their maximum i.e. to their plated MTPLMs of 1850 kg and 2000 kg, which if used would exceed the vehicle's MTPLM by 350 kg.  If the vehicle is not loaded in this way, the driver is justified using lower pressures if they are recommended by the tyre manufacturer, which they are.  The issue I suggest is how much lower.  For example, someone might measure their front axle mass as 1400 kg.  This could mean that the N/S front wheel has a load of 800 kg and the O/S wheel 600 kg.  If the pressure has been set for a load of 700 kg, the O/S tyre will be unsafe which will be the driver's fault.  Added to this, the actual axle mass might be higher than it was when it was last measured and the front cold tyre pressures might have dropped since they were last set.  In both cases it increases the driver's fault.   The risk of this happening is reduced if a higher cold tyre pressure is used.  The issue then is how much higher.  Peugeot recommend a front tyre pressure for a front axle mass that is 7% higher than its MTPLM for C tyres and 15% higher for CP tyres.  TyreSafe recommend 10% higher for both types of tyre for any mass.  When I discussed it in Oct last year with Continental UK's technical director, he supported the TyreSafe approach but for my front TPMS set around a maximum front axle mass of 1500 kg, he settled on a front tyre pressure of 3.4 bar which is the pressure for an axle mass that is about 5% higher.  It appears that Bailey also use this approach for its similarly loaded Peugeot motorhomes.   The bottom line is that the driver must not allow the pressure of any tyre under any circumstance to drop below that recommended by the tyre manufacturer to support the load on the tyre, which in Continental's case can easily be calculated from their Databook, which uses unadulterated ETRTO figures, by dividing the axle mass by 2.


Last edited by Caraman on Mon Apr 05, 2021 4:34 pm; edited 1 time in total (Reason for editing : typo)
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Post by jeffhornsey Mon Apr 05, 2021 5:07 pm

A point of interest. I have a Auto-Sleeper Warwickxl on a Peugeot base van. I have a aftermarket TPMS. I've noticed that the temperature of the right rear tyre is higher than the other three after a few miles on the motorway, and regardless of the sun position. Puzzling as all the pressures were correct and the axle loadings checked on a weighbridge were ok.  I then realised that the exhaust pipe discharges just in front of the right rear wheel! Could this be the cause?
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Broadway Tyre Pressures! Empty Re: Broadway Tyre Pressures!

Post by jadatis Mon Apr 05, 2021 5:35 pm

As long as you did not do weighing, I can estimate a weightdivision over the axles, with spreadsheet I made for it.
Then calculate a pressure for it.
Also my estimation is that you can use lower pressure on front, but the full 5.5 bar/ 80 psi on rear.

Need next to calculate.
For the weightdivision  total length of motorhome, and wheelbase in foot,  cm or inch, whatever you like, I dont have problems with converting.
Then I will asume an overloaded mh by 10% so 3500kgx1.1 is 3850 kg, so x2.2045 is 8487 lbs.
If you dont give it I assume 90cm/3foot/ 36inch in front of front axle.
And I need to know if its a campervan, so all iron body, and no alloy/wood construction behind cabine.
I assume a campervan to have its gravity- point 45 to 47% of total length behind front.  But for instance watertank not in front, but totally in back, can bring it to 55% , as I lately calculated for one.  So if you have these extra weigts at  extraordinary places , write it too.

Then with these weights, I will calculate the needed pressure with maximum reserve with still acceptable comfort and gripp.

A campervan often has more weight on front then " normal " one, so the 50 psi , one wrote then will peobabbly to low.  But mayby I will have to get back on that, after calculation.

Also need tyre-specifications,maxload, loadrange/plyrating, but give sises too.
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