sjh1341 Posted July 23, 2011 Share Posted July 23, 2011 Tim, I know we spoke re the above and we thought 5 bar, but can anyone confirm what tyre pressures we should run at? Link to comment Share on other sites More sharing options...
Tiny Tim Posted July 24, 2011 Share Posted July 24, 2011 Hi Steve The listed pressures from the Sarasota Handbook are 47psi front and 55 psi rear. Can you send me your home e-mail address - your work on comes back as out of office! Link to comment Share on other sites More sharing options...
Derek Uzzell Posted July 25, 2011 Share Posted July 25, 2011 Tiny Tim - 2011-07-24 11:58 AM Hi Steve The listed pressures from the Sarasota Handbook are 47psi front and 55 psi rear. Can you send me your home e-mail address - your work on comes back as out of office! The pressures you've quoted are worryingly low in my view. I'm very wary of advising on suitable tyre pressures for a motorhome without knowing exactly what tyres are fitted to the vehicle and what the motorhome's axle-loadings are when the vehicle is fully loaded (which will require the vehicle to be weighed of course). Nevertheless, an over-cab Sarasota is far from small, with a substantial rear overhang and, if I had purchased one and was prepared to take an educated guess at suitable tyre pressures, I'd opt for around 4.1bar(Front) and 4.7bar(Rear) - say 60psi(Front) and 68psi(Rear) - as a start-point prior to loading up the vehicle, taking it to a weighbridge and then seeking expert advice from the manufacturer of its tyres. In fact (assuming that sjh1341's Autocruise has 'camping-car' tyres designed to handle an inflation-pressure of 5.0bar (72psi approx)) it might be wisest to use that pressure front and rear as a stop-gap measure until the suitability of the Sarasota handbook recommendations has been confirmed absolutely. It's far safer to run tyres above 'ideal' pressures, even though this may well result in a harsh ride, than run them under-pressure when the resultant overheating can result in catastrophic tyre failure. Link to comment Share on other sites More sharing options...
Brian Kirby Posted July 25, 2011 Share Posted July 25, 2011 May I endorse what Derek says above? The only Sarasota I could find listed with any details, quotes an MAM of 4150kg. If this is correct and typical, I too would advise 72psi/5.0bar all round until the van is weighed fully laden, individual axle loads taken, and the tyre manufacturer's advice on pressures sought. As an alternative, you could go here http://tinyurl.com/ygj67lm and download the "Motorhome Tyres" leaflet (a good idea in any case), and take pressures from that - but only if the tyre size, speed rating and load index can all be matched: but, you'll still need to get the fully laden axle weights from a weighbridge first. Link to comment Share on other sites More sharing options...
mikemoss Posted July 25, 2011 Share Posted July 25, 2011 Our Besscarr, which has exactly the same layout and very similar underpinnings, runs on 59psi front and 65psi rear. Max weight 3400kg, max rear axle load 1900kg. I know that's a bit on the apples and pears side, but thought it might just help. 72psi sounds rock hard and could possibly be dodgy for non-camping tyres. Link to comment Share on other sites More sharing options...
Tiny Tim Posted July 25, 2011 Share Posted July 25, 2011 The pressures that I listed are those given in my Sarasota Handbook (not the Peugeot one) and it states 'as recommended by Michelin'. So unless you have seen something that supersedes that....... Link to comment Share on other sites More sharing options...
Brian Kirby Posted July 25, 2011 Share Posted July 25, 2011 I think all we are saying is that the handbook may contain a misprint. If you happen to know the tyre sizes, and type, fitted, and the maximum axle loads, for a Sarasota, it would be possible to be clearer. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted July 26, 2011 Share Posted July 26, 2011 Tiny Tim - 2011-07-25 8:38 PM The pressures that I listed are those given in my Sarasota Handbook (not the Peugeot one) and it states 'as recommended by Michelin'. So unless you have seen something that supersedes that....... This is a link to one of several on-line adverts relating to overcab Autocruise Sarasotas (with extra details available by clicking on that webpage's +info button) http://cars.mitula.co.uk/cars/sarasota,%20special%20editioneasy It should be plain from the photos that this is not a 'compact' motorhome. Although I've GOOGLE-ed fairly hard it has not proved straightforward to obtain reliable dimensional/weight information, but it would appear that the over-cab Sarasota was built on a LWB chassis with air-assistance for the rear axle, may well have been around 7.5m long and probably had (as Brian Kirby said) a MAM of 4150kg. This specification points to a 'maxi' chassis with 16" wheels and 215/75 R16C tyres that originally (in 2005/2006) were probably Michelin "XC Camping" or Michelin "Agilis Camping". Those 'camping-car' tyres were designed to handle up to 5.5bar (approx 80psi) inflation pressure and it was commonplace for Fiat/Peugeot (and motorhome manufacturers) to recommend pressures of 5.0bar/72psi(Front axle) and 5.5bar/80psi(Rear axle) for motorcaravans with the specification I've just mentioned. On another recent forum-thread 'lankyharry' said: "We've had our autocruise sarasota from new....The handbook is clearly cobbled from another autocruise (ours is the 6 berth overcab model)...." It's normally simple for a motorhome owner to obtain weight-limit data for his/her vehicle as the vehicle's maximum weight (MAM), maximum train weight, and front or rear maximum axle-loadings are shown on the vehicle's VIN-plate. I don't know where the VIN-plate (or possibly "plates") is/are on an over-cab 6-berth Sarasota, but if sjh1341 (or another owner) can quote the weight data on the VIN-plate, it would help to establish whether or not the 47psi/55psi figures in Tiny Tim's handbook are realistic. (I've reached my patience threshold on this. A warning has been given (by me and echoed by Brian Kirby) that the figures in Tiny Tim's Sarasota handbook MAY be markedly too low. I don't care if this warning is ignored as - if the handbook recommendations are unsuitable - it won't be me that will be operating a motorhome with tyre pressures possibly 15psi below what they should be and, should a tyre fail from overheating as a consequence, the likelihood that the consequences of that failure will affect me personally approach nil. Basically, "Please yourselves and the best of luck!") Link to comment Share on other sites More sharing options...
Tiny Tim Posted July 26, 2011 Share Posted July 26, 2011 Aint life fun! All of us new Sarasota owners are really grateful for this input - but I'm sure I can be forgiven for quoting the manual in the absence of specific evidence. I have now checked the tyres and those fitted to my Low Profile Sarasota (all dimensions the same as the 6 berth but without the overcab) are as you have stated 215/75/R16 C Michelin Camping and there are various mentions on the sidewall of 80psi. What is more, I have found the details on a plate inside the drivers door and it states 79.5 psi cold. Humble pie being steadily consumed and thanks again to those who took the time to try and steer us on the right path. STEVE. In case the overcab version varies from mine, the plate that I refer to is on the back of the drivers door frame under the lock. Tim Link to comment Share on other sites More sharing options...
mikemoss Posted July 26, 2011 Share Posted July 26, 2011 No need to get tetchy folks (which seems to be a feature of this particular forum) and my apologies for giving well-meaning but inappropriate suggestions based on the recommended pressures for our Bessie E695. Similar layout, yes, but much lighter chassis (3400kg). Link to comment Share on other sites More sharing options...
Derek Uzzell Posted July 26, 2011 Share Posted July 26, 2011 Tiny Tim - 2011-07-26 10:38 AM Aint life fun! All of us new Sarasota owners are really grateful for this input - but I'm sure I can be forgiven for quoting the manual in the absence of specific evidence. I have now checked the tyres and those fitted to my Low Profile Sarasota (all dimensions the same as the 6 berth but without the overcab) are as you have stated 215/75/R16 C Michelin Camping and there are various mentions on the sidewall of 80psi. What is more, I have found the details on a plate inside the drivers door and it states 79.5 psi cold. Humble pie being steadily consumed and thanks again to those who took the time to try and steer us on the right path. STEVE. In case the overcab version varies from mine, the plate that I refer to is on the back of the drivers door frame under the lock. Tim As your Sarasota has Michelin tyres, what I suggest you do is contact Michelin http://www.michelin.co.uk/contact provide EXACT details of your tyres based on the information on the tyres' sidewalls (for example, Michelin "XC Camping" 215/75 R16C 113Q), give Michelin weight-related details from your motorhome's VIN-plate (most importantly the maximum permitted loadings for the front and rear axles) and ask for inflation-pressure recommendations. Michelin's current policy seems to be, for motorhomes fitted with 'camping-car' tyres, to recommend 80psi for the vehicle's rear tyres irrespective of the VIN-plate rear-axle loading datum, or even irrespective of a rear-axle loading measured by a weighbridge. But at least you should get a 'worst case' pressure recommendation for your front tyres. For motorhomes fitted with Michelin "XC Camping" 215/75 R16C tyres, Hobby's 2004 User Manual advised 4.8bar (70psi approx) and 5.5bar (80psi approx) for front and rear tyres respectively, whereas Pilote's similar-vintage Manual advised 5.5bar/80psi, front AND rear for similar-chassis motorhomes with those Michelin tyres. These high pressure-recommendations tend to be the norm for motorhome manufacturers, which is one reason why the Autocruise Sarasota handbook advice seems suspect. Weighing your motorhome in FULLY-LOADED condition would allow you to establish how close to the VIN-plate axle-load maxima the 'real world' loadings are. If the measured axle loadings prove to be significantly below the VIN-plate figures, then it might be possible to safely reduce the pressures for the tyres on one (or both) axles to improve ride comfort. Link to comment Share on other sites More sharing options...
Brian Kirby Posted July 26, 2011 Share Posted July 26, 2011 Tiny Tim - 2011-07-26 10:38 AM Aint life fun! All of us new Sarasota owners are really grateful for this input - but I'm sure I can be forgiven for quoting the manual in the absence of specific evidence. I have now checked the tyres and those fitted to my Low Profile Sarasota (all dimensions the same as the 6 berth but without the overcab) are as you have stated 215/75/R16 C Michelin Camping and there are various mentions on the sidewall of 80psi. What is more, I have found the details on a plate inside the drivers door and it states 79.5 psi cold. Humble pie being steadily consumed and thanks again to those who took the time to try and steer us on the right path. STEVE. In case the overcab version varies from mine, the plate that I refer to is on the back of the drivers door frame under the lock. Tim Consulting the manual is very creditable, it is amazing how few try this path before posting! :-) If the manual is wrong, it is hardly your fault. How could it be? However, that plate you've found is not the one that is needed! :-) What you need to find is the VIN plate, that starts with the VIN (vehicle identification number, or chassis number), and then lists below it, one below the other, four numbers, numbered 1 to 4. 1 is the MAM, or maximum permissible weight for the laden vehicle. 2 is the GTW, or gross train weight, which is the maximum combined laden weights for the vehicle plus any trailer. 3 is the maximum permissible load for the front axle, and 4 ditto for the rear axle. It is the values against numbers 3 and 4 that are needed, to establish what are the safe working pressures for tyres subject to these potential loads. Next, quote the full tyre size data, such as 215/75 R 16C (maybe 16CP) 113/111R, or similar (all on the side of the tyre - worth just checking they are all the same). The 113/111 (or whatever is there) is the load index, which governs the load the tyre can sustain, and R (or whatever letter is there) is the speed index, which governs the maximum sustained speed at which the tyre can support that load. If we can have that, I think we can state, with reasonable confidence, what tyre pressures should be adopted until the van is weighed fully laden, with the actual axle loads recorded. Once the actual laden axle loads are known, they can be quoted to the tyre manufacturer, along with the full tyre data as above, and they should be able to recommend slightly lower pressures that are correct for the load actually being carried - with a resulting improvement to ride quality, braking performance, possibly directional stability - and almost certainly the preservation of your fillings! :-D Link to comment Share on other sites More sharing options...
Harvey Posted July 26, 2011 Share Posted July 26, 2011 I'll stick my oar in , in case it helps.........If it doesn't, well, so be it. :-D I have a 2006 Starblazer which I know is approximately the same size as the Sarasota. Having said that, there were two sizes ( lengths ) of Starblazer. Mine is an 'XL' which is 24ft and the shorter one was 22ft 11inch approx. Mine has a MAM of 4150kg. It is based on a 350LWB Peugeot Boxer which I believe had a MAM of 3970. The shorter Starblazer had a MAM ( according to the 2006 brochure ) of 3700kg. The brochure does not suggest that the 'Highline' with bed over cab has a different MAM, only a different 'Mass in running order' ( so a lower payload ). The MAM increase on mine ( over and above the Boxer 350 LWB ) was achieved by the fitting of 'Kuhn' air suspension on the rear axle. This raised the rear axle max load from 2120 to 2300kg. It did not change the front axle max. This fitting was carried out by Leisure Vehicle Supplies Ltd for Autocruise at the time of the vehicle build. The Boxer rating plate is under the bonnet on the front apron; drivers side and on mine has been overlaid by LVS with a plate with the new weights. I also have an 'Approval Certificate'. The handbook for my Starblazer XL also states '"Tyre Pressures ( as recommended by Michelin Tyres ) Front 47psi. Rear 55psi." I did contact Michelin for tyre pressure advice in 2008 and although they did state that they preferred to quote pressures for the actual axle weights from a weighbridge they did suggest that for the gross axle weights they should be: Front 60psi and rear 70psi ( for axle weights of 1850kg and 2300kg respectively.) They didn't comment on the fact of the stated pressures in the Autocruise handbook. I hope some of that may be of use. Harvey Link to comment Share on other sites More sharing options...
Tiny Tim Posted July 26, 2011 Share Posted July 26, 2011 Brian Kirby - 2011-07-26 2:50 PM Tiny Tim - 2011-07-26 10:38 AM Aint life fun! All of us new Sarasota owners are really grateful for this input - but I'm sure I can be forgiven for quoting the manual in the absence of specific evidence. I have now checked the tyres and those fitted to my Low Profile Sarasota (all dimensions the same as the 6 berth but without the overcab) are as you have stated 215/75/R16 C Michelin Camping and there are various mentions on the sidewall of 80psi. What is more, I have found the details on a plate inside the drivers door and it states 79.5 psi cold. Humble pie being steadily consumed and thanks again to those who took the time to try and steer us on the right path. STEVE. In case the overcab version varies from mine, the plate that I refer to is on the back of the drivers door frame under the lock. Tim Consulting the manual is very creditable, it is amazing how few try this path before posting! :-) If the manual is wrong, it is hardly your fault. How could it be? However, that plate you've found is not the one that is needed! :-) What you need to find is the VIN plate, that starts with the VIN (vehicle identification number, or chassis number), and then lists below it, one below the other, four numbers, numbered 1 to 4. 1 is the MAM, or maximum permissible weight for the laden vehicle. 2 is the GTW, or gross train weight, which is the maximum combined laden weights for the vehicle plus any trailer. 3 is the maximum permissible load for the front axle, and 4 ditto for the rear axle. It is the values against numbers 3 and 4 that are needed, to establish what are the safe working pressures for tyres subject to these potential loads. Next, quote the full tyre size data, such as 215/75 R 16C (maybe 16CP) 113/111R, or similar (all on the side of the tyre - worth just checking they are all the same). The 113/111 (or whatever is there) is the load index, which governs the load the tyre can sustain, and R (or whatever letter is there) is the speed index, which governs the maximum sustained speed at which the tyre can support that load. If we can have that, I think we can state, with reasonable confidence, what tyre pressures should be adopted until the van is weighed fully laden, with the actual axle loads recorded. Once the actual laden axle loads are known, they can be quoted to the tyre manufacturer, along with the full tyre data as above, and they should be able to recommend slightly lower pressures that are correct for the load actually being carried - with a resulting improvement to ride quality, braking performance, possibly directional stability - and almost certainly the preservation of your fillings! :-D Thanks Brian - and I thought that I had got it sussed! The later posting by Harvey is also food for thought. It seems that I have some more work to do. Tim Link to comment Share on other sites More sharing options...
Brian Kirby Posted July 26, 2011 Share Posted July 26, 2011 So, the front axle max is (probably, pending confirmation from the VIN plate) 1850kg and the rear (ditto) 2300kg. From the Tyresafe "Motorhome Tyres" leaflet, only 215/75R 16CP 113 (speed rating not quoted) tyres are quoted as being suitable for an axle capacity of 2300kg, at 80psi. These are the camping tyres. For the same axle load the standard 215/75R 16C 113 (commercial) tyre requires 70psi, as you report Michelin saying. However, this begs the question as to whether the tyres fitted are Camping tyres, or the normal commercial variety. In either case, the tyres are being operated at the absolute maximum load, and pressure, they can sustain. Sustaining high speeds on motorways would, I think, be unwise. Running at the handbook recommended pressures, especially if the rear is anywhere near its maximum load, would appear to be substantial under inflation to the point of being dangerous. If the tyres have been run at this load and at the handbook pressures, they will have been getting pretty hot, and I would suggest are probably by now blow-outs waiting to happen! Be warned, there is a real safety issue here, until proved otherwise. That handbook is dangerous! :-( Link to comment Share on other sites More sharing options...
Harvey Posted July 27, 2011 Share Posted July 27, 2011 Brian and all, Just to clarify: the tyres on my Starblazer, for which Michelin suggested the pressures in my previous post are:-- 'Michelin XC Camping' 215/75 R16C. As a further point of interest I had my 'van on a weighbridge and the results were:- Front 1580kg .... Rear 2040kg. That is as loaded for a holiday with two people on board but I don't know how much diesel, or water I was carrying. so have plenty of spare capacity anyway. Recent MOT test showed the rear at 2000kg but I think that is not as accurate as weighbridge.. Incidently the Kuhn air suspension on the Starblazer needs a pressure of '1 to 2 bar' according to the Autocruise handbook whereas the Kuhn instal instructions say 1 bar for the '6 inch' and 2bar for the 8 inch. Will confirm that later. Harvey Link to comment Share on other sites More sharing options...
Harvey Posted July 27, 2011 Share Posted July 27, 2011 Appologies; I was called away from the computer and now cannot edit my previous post. Those pressures for the Kuhn suspension should be: 2 bar for the 6 inch bellows and 1.5 bar for the 8 inch bellows. I assumed that those bellows measurements are for the diameter and I measured mine at approx. 8 inches. This is slightly off the topic of tyre pressures but is relevant to maximum axle weight and 'firmness of ride'. Harvey Link to comment Share on other sites More sharing options...
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