Flat spots

All you need to know about flat spots

Does a flat spot occur over night and is it due to the temperature? 
Yes. With cold temperatures the elasticity of rubber sinks. Heavy vehicles that are parked outside in winter often don’t run smoothly on their first kilometers the next morning. If this problem is solved by itself after a short time then everything is fine. Should the ride still be rough one should also think of defect steering shock absorber or objects that may stick in the tire.   

Flat-spot! What now? Does it disappear automatically during driving? 
The more the tire has been deformed due to long periods of standing still the higher is the danger of constant defects of the material. Drivers of campervans know that it can be a long and rough ride.. Should it be over after days or weeks the campervan goes back to the garage already. It’s a torture for the wheels. In the end it affects the durability of the tires and costs a lot of money to replace. 

Which type of tires gets flat spots – diagonal or radial tires? 
As a matter of fact it’s the diagonal tire. The reason is not based in the general type of construction but in the used material. Nylon fabric in combination with thermoplasts. Nowadays’ radial tires are more resistant against flat spots as long as they are not high speed tires. The softer the rubber, the flatter the profile, the higher the risk of getting flat spots. In the end the crucial point is the period of standing still and the contact pressure.  

How to avoid flat-spots – what are the alternatives to an air pillow? 
If you want to save the money for air pillows you have to invest time: Either you drive your vehicle regularly or use a set of old and used tires for the time of standing still in the garage. If in that case a visit in the workshop is needed the costs for the flat-jack® air pillows will soon be compensated very quickly – not talking about the comfort and time saving! 

Jacking up or inflating? 
In the case of jacking up a vehicle e.g. rubber parts on bearings and axles and the entire chassis are exposed to heavy load where it shouldn’t be.and that have not been constructed for such heavy loads. Damages on the suspension often result from inproper storage on jacks. The solution with flat-jack® air pillows is definitely the better way when it comes to safety and comfort. New: evolution gel – the gel tyre pillow. 

Do you need an additional protection using the flat-jack pillows on  
Yes, if you can not clear space of sharp objects or stones before use, we strictly recommend to place a protection underneath.

flat-jack® air pillows

All you need to know about our flat-jack air pillows

How much weight does a flat-jack® pillow hold? 
Up to 900kg/ 1980lbs per wheel

How long is the warranty?
2 years

Are the prices valid for 1 pillow or for a set?
The prices are valid for 1 pillow.

How do you inflate the flat-jack® air pillows?
Use a bicycle pump or a mini compressor which are suitable for car valves.

What is the weight of the pillows?
S – vintage 480g/ 1 lbs, M – sport 590g/1,3lbs, L – supersport 690g/1,52lbs

Are the sizes S,M,L sold per set and how many pillows are in a set?
The sizes are sold as single pillows but you should always use them in pairs per axle.e.g. 2 M in the front and 2 L in the rear.

Which size pillow is the right one for my tyre width?

• S – vintage up to tyre width 195mm/7,68 inch
• M – sport up to tyre width 255mm/10,04 inch
• L – supersport up to tyre width 345mm/13,58 inch

flat-jack® camper and camper plus 

All you need to know about our camper edition

How much weight does a camper/camper plus pillow hold? 
Up to 1500kg / 3307lbs per wheel

Up to which height can a wheel be lifted?
With the camper pillow the wheel can be lifted up to 6cm/ 2,35 inch and with the camper plus up to 12cm / 4,7 inch. Please stop inflating when vehicle stops lifting. Don’t exceed the maximum pressure that is stated on the air pillow. Too high pressure can result in destruction of the flat-jack®.

Can the pillow be used on rough ground?
Please clean rough ground from sharp stones or other sharp objects in order not to destroy the pillow. We recommend to use a padding like a car mat or similar to protect the pillow.

What is the difference between the flat-jack® sizes S – vintage, M – sport, L- supersport, camper and camper plus?
The sizes S,M and L are constructed for cars, to protect tyres and avoid flat spots on the same. The uniqueness of our flat-jack® pillows also results from reduction and compensation of lateral forces and tensions on the entire chassis.The camper and camper plus construction also carry these advantages but additionally serve as practical, light weight and super easy to use levelling aid on uneven ground.

The tyre width on my mobile home is 285mm/ 11,22 inch ( all terrain tyres). Can I use the camper plus pillows as levelling aid?
No problem but please keep the necessary distance to the valves in order not to drive over them.

Can the camper plus pillow also be used as levelling aid when the tyre size 165/70 R13 is smaller than written in your brochure?
Yes, there is no minimum size.

Can the flat-jack® pillows be piled?
The camper version can be piled (max. 2 pillows) although we don’t recommend to do that. If you need to have a higher levelling aid we recommend to buy the camper plus version. Don’t pile the camper plus version as the stability of the mobile home can not be guaranteed any more.

How long is the warranty?
2 years

Are the prices valid for 1 pillow or for a set?
The prices are valid for 1 pillow.

How much does a pillow weigh?
The camper version weighs 590g / 1,3lbs and the camper plus version weighs 960g / 2,12lbs

Up to which temperature can the camper/camper plus pillows be used and is an additional protection against the sun necessary?
When using the pillows one has to observe the maximum pressure that is stated on the flat-jack®. Never exceed the allowed pressure. We recommend to use less pressure especially when the outside temperature is quite hot. An additional cover/protection against intense exposure to the sun is strongly recommend. In cold climate there is no extra protection needed.

What are the measurements of the camper/camper plus pillows?

• Camper length 66cm/26 inch – width 37cm/14,6 inch,
• camper plus length 66cm/26 inch – width 43cm/16,9 inch

What do you have to take care of if your mobile home has double tyres?
Only the outer tyre is placed on a pillow.

In the case of a twin axle mobile home can one place 2 pillows one behind the other?
Yes, 2 pillows can be placed one behind the other.

How do you inflate the flat-jack® air pillows?
Use a bicycle pump or a mini compressor which are suitable for car valves.

Can the flat-jack® air pillows be used to save the tyres from flat spots during storage periods?
Yes, absolutely ( that’s what they originally were produced for)

When deflating the pillows sometimes the special construction inside (chamber walls) fold down in the “wrong” direction. Does this cause a problem?
No, not at all. The function of the pillow is still guaranteed.