Tyre Replacement Advice

[pachapapa]

I have a Citroen Romahome registered 02/05/86.
I purchased vehicule in May 1996, when it had Michelin Classic 145/80 R13 75 T tyres fitted; I still have one as a spare.
In 1998 to pass french Control Technique (MOT) a local tyre dealer fitted Goodrich 155/80 R13 79 T tyres, initially two and later the remaining two to make a full set.
The tyres all have plenty of tread but three have cracks on the sidewall and have failed the Control Technique this year 2008.
I am informed that the regulations in france have changed and I must fit reinforced tyres.
I am reluctant to return to 145 width but I also cannot in any case find anything in this size chich has a reinforced or commercial (camionette) rating.
I find to my surprise that the closest equivalent in the ETRTO tables for a 145/80 R13 tyre is in fact a 165/70 R13; it would appear that the 155/80 R13 fitted in 1998 would not comply in 2008.
When surfing the net I find that Continental proudly announce a CP tyre for campervans. When I mention the letters CP to local tyre fitters they look puzzled and shake their heads. However they are happy with the single letter C, intended for a light commercial vehicule. I live in France Profonde where every other vehicule is a C15, Kango or Berlingo.
Surfing the net I find tyres ranging from an expensive
Continental VancoContact 165/70 R13C 88/86R 6PR at € 112
to TOYO H 08 165/70 R13C 88/86R at € 52.
I presume that a "C" tyre is acceptable for a Romahome.
I was quoted € 57 for a Nankang 155/80 R13C 85 T fitted which is not a bad price, but I am not sure about the equivalence to 145/80s, on visiting the dealer the lady with the computer is adamant that the Dunlop SP9C which she has in stock are just the thing I need.
Be most grateful for any counsel and advice.

[ant]

Hi Pachapapa.
The tyre regs in this country would allow an 86 C15 to have 79T rated tyres ( Chassis Number must have PB in it not PP). My advice would be to fit 155 13 Reinforced, The commercial tyres don't normally give any other numbers like 155/80 13. Nankang make an 8 ply 155 13 which is a good enough tyre to meet all the loads a C15 should take.
I would not fit a 145 anything or a 165 anything.
The most important thing to get right is the load each tyre can carry. On the chassis plate you'll find the front and back axle limits ( back axle on a PP c15 is 990Kg less on yours). The tyres must be able to carry half that wt each ie 495 Kg, car tyres only go to about 430Kg and are therefor not man enough for the job.
Hope this helps
Ant

[pachapapa]

Hi there, thanks for your quick reply.
The front axle is 680 kg, rear axle 800 kg.
Chassis No:
VF7VDPA002PA5248 so no PP or PB, just a PA.
Weight no load 1,270 kg
Weight loaded 1435 kg
This morning I contacted a M. Cousineau, who owns a tyre fitting garage at Cherves in the middle of a rural area and he seems to know about C15 vans and pick-ups. At first when I quoted the year he was adamant that it had 155/80 R13 fitted as original; I explained that I still had a 145/80 R13 75 T from when I purchased it second hand. He asked if it was perhaps petrol driven, which it is.
He says that diesel were fitted with 155's and petrol with 145's.
The use of the Carte Grise (registration document) on the official computer gives the following;
145R13 REINFORCED(78R) ou similaires.
There appear to be no Reinforced 145's manufactured currently, so the similar route is the only valid option.
The closest equivalent tyre is a 165/70 R13 which is only 0.18% difference in diameter to the 145/80 R13.
Whereas the 145/80 to 155:80 gives a difference of 2.8%, close to the 3% maximum.
The 165/70 is slightly smaller in diameter and height.
I am now in process of ordering four tyres on line from
special-pneus.fr/achat/detailPneu.php?pneuID=7141&largeur=10&hauteur=12&diametre=2&page=1
with delivery to Garage Cousineau,Cherves,Vienne,Poitou.
The 88 load rating will give 560 kg to play with, it will be useful when collecting logs or floor tiles, etc.
I rather think it has been overloaded in the past, like four teenagers plus baggage, frankly surprised that the original 75 T's didnt explode.
I will keep you informed of developments.

[ant]

Hi Pachapapa.
Don't get to see many petrol Romahomes, the PA in the chassis number denotes petrol engined. In the past I've seen 165 R 13 tyres fitted to the Romahomes ( Diesel) and almost all of them have rubbed the inside of the tyre. this may be a combination of wider tyre and tired rear susspension. I would just be aware of that fact and check the tyre more often.
Ant

[pachapapa]

Hi there, sent cheque off today to tyre on line store.
FiFi has only done 48,886 miles to date, so mechanically is not in bad shape. The suspension seems pretty tight with no notable rebound., perhaps the tyres have absorbed most of the up and down motion, they always looked a bit overloaded to me.
I have been checking clearances for the tyres and their is a potential source of interference with the chassis member at the back of the wheel arch. The current 155 tyres have a lateral clearance of 8 mm between the projected chassis position and the widest position on the tyre wall. The widest portion of the tyre is 5 cms below the tread and there is a distance of 7 cms between potential chassis interference point and widest position on tyre wall. In principle a 155 tyre would never touch unless there is deformation of the tyre.
The mounting of a 165/70 tyre will give an increase in tyre height from rim of 0.7 cms compared with the current 155/80 (extra miles per gallon). In theory the new tyre will overhang an extra 5 mm to the rear, still leaving a nominal 3 mm of clearance, however the suspension arm would be required to allow the tyre to move vertically through a distance of 7 cms before the interference position would be reached ( a heavy load and a bumpy road ). I would be less confident with a 165/80 which would give an increased tyre height of 1.65 cms.
Here's hoping that judicious skimming with a diamond disk on an angle grinder will not be necessary.

[pachapapa]

Hi there, just a quick update to the tyre replacement saga.
I got the Toyo tyres fitted on all four wheels and kept trhe best of the old 155/80's as a spare.
The fitted tyres are
TOYO H 08 165/70 R13C 88/86R
and the vehicule has passed the Control Technique retest( French MOT), so it is OK for a further two years.
A small point for UK viewers, the french CT lasts for two years and on testing one has a period of TWO MONTHS to correct any points of failure.
The new tyres are a "C" rating suitable for a light commercial vehicule and the change in driving characteristics is really dramatic due to the better sidewall support.
The pronounced roll on corners with the 75 T tyres no longer occurs and this was particularly bad with the original 135/80R13 75T tyres.
In my opinion any campervan due to it's height has a tendency to roll and this factor is more disconcerting than the axle load on the tyres.
The clearance on thr rear tyres remains at 8 mm using a handy machette with a dead straight long blade as a reference for measurement.
The drive and handling has been much improved.