WheelchairDriver.com  

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Updated:  05-Dec-09

Welcome

1. POWERCHAIR ONLY:
Detailed Full PowerChair Related ONLY Menu HERE

2. VEHICLE ONLY:
Detailed Wheelchair Accessible Vehicles ONLY menu HERE

3. EVERYTHING ELSE:
Detailed Menu of Everything else HERE!


MY OWN VEHICLES:
Dodge Grand Caravan


VW Caravelle VR6

MY HOME BUILT ULTIMATE POWERCHAIRS:
My SLIGHTLY Modified Improved Powerchair

Part 1 | 2 | 3 | 4 | 5 | 6

My VERY Modified Off Road & All terrain DO ALL Powerchair!
Part 1 | 2 | 3


MISCELLANEOUS POWERCHAIR RELATED:
What Goes Wrong Power Wheelchairs

Powerchair Tyres

Drive your Powerchair by Radio Control

Powerchairs & Range


Off Road DO ALL Indoor & Outdoor Powerchairs

Off Road ONLY Outdoor Powerchairs & 4x4
Page 1 | 2

Manual or Electric Wheelchair?

Why ALL Powerchairs NEED  to be Off Road Capable!

Choosing  a Suitable Powerchair

Wheelchair Width


BATTERY AND ELECTRICAL (POWERCHAIRS & SCOOTERS + MOTOR VEHICLES):
Batteries for Both Vans & Power Wheelchairs


Inverters & Chargers

Very flexible charger!


Charging Batteries

Fast Charge Your Power Wheelchair

Which batteries to buy


"DRIVE FROM A WHEELCHAIR" VEHICLES:
Dodge Grand Caravan 1

Dodge Grand Caravan 2
Dodge Grand Caravan 3
Dodge Grand Caravan 4

Latest 2008 2009 2010 Disabled Converted Dodge Chrysler And Voyager Minivans
 
Chrysler Voyager Entervan Diesel

Suzuki Wagon R

More Here

Mercedes Vito - soon!
Kia Sedona - soon!


INSURANCE:
Modified Disabled Vehicle Insurance

Breakdown Cover

USED VEHICLES & OTHER EQUIPMENT:
Disabled Adapted Cars

WHEELCHAIR TRANSPORT
& DRIVE BY TRANSFERRING:


VW Caravelle

Dodge Grand Caravan can be used to transport up to 4 Wheelchair Seated Occupants

Fiat Doblo

Renault Kangoo - soon!
Citroen Berlingo
- soon!
Citroen Dispatch
- soon!
Kia Sedona
- soon!
Volkswagen Sharan
Mercedes Vaneos
Toyota Hiace
Fiat Multiplas
(Wheelchair
passenger travels in the front)

Kangoo ASSIST
(wheelchair
passenger transfers & drives)


ESSENTIAL DISABLED
EQUIPMENT STUFF:

Understanding


Grabbers

Puncture proof tyres

Run Flat tyres

Tyre Weld Aerosol

Fuses!

Spare Key


Wheelchair Ramps

Small Generator

Tools!


VEHICLE ADAPTATIONS:
Control Systems etc
Hand Controls Manual
Hand Controls Electronic
Van / Car Door openers
Van / Car Wheelchair Tie Downs

 


OTHER STUFF:
Used Disabled Equipment for sale

How to lose weight  FAST!

Email about modifying powerchairs

Keep it looking new 1 2

My Accident!


Climate Change

Electric Cars are a Joke!

Disclaimer & About Me

Site Map

Contact

Links

John Williamson


Powerchair Tyre Pressures.

Just like in your car or motorcycle a Powerchair has a "recommended" tyre pressure. But this is just a guide. The correct tyre pressure is the one that suits you and your specific compromises best.

I used to race bikes (and cars) before landing in a wheelchair... There is no such thing as a "correct" tyre pressure. 

If you want an easy comfortable ride outdoors because you have muscle spasm issues, pressure sore problems or just because you prefer less vibration it can help (a little) to run with a lower tyre pressure that the manufacturers "recommended" pressures. Its your choice! This is usually chosen to be about 30 to 35 PSI depending on who manufactured your power wheelchair. (Or wheelchair)

But they don't even know your weight!  That makes a huge difference all on its own. Adults go from very small and light (say 100 pounds or less) to well over 300lb.  

So even if there was a "correct" pressure to use, it still wouldn't be correct for most people!  If you double the weight a tyre has to carry, then you have to double the pressure to maintain the same tyre shape and contact patch area.  This is one of the many problems of foam filled tyres. No adjustability for user weight. Take a look at the door pillar on your car. More load? More passengers? Requires more pressure. Its the same in your powerchair.

And they don't know your condition. Some people cannot cope with simple vibration or the kind of shocks that hard "correctly" inflated tyres give on our uneven streets for a large bunch of medical reasons. "Suspension" as fitted to current Powerchairs just doesn't cut it. It can "help|" with the big bumps but does nothing to help with smaller high frequency bumps/vibrations such as you experience on cobbles or similar sized bumps.

It can help slightly on bigger jolts but we travel much too slowly for it to ever be very effective. Our wheels are too small! So for these people effected (and myself included) running with lower tyre pressures helps. 

Related Note: I actually removed the (useless) suspension and fitted special fat really low pressure tyres instead to my own powerchairs eventually!   The real problem is that powerchair manufacturers fit tyres with too small sidewalls for comfort. But I digress. (Here if you are interested)

So what other effects does running with lower*** tyre pressures have?  (***lower than advised)

a) causes slightly faster tyre wear generally but over a wider area of the tyre rather than just the middle.

b) causes more grip on snow or slippery conditions (but not hugely so, as the tyres are too small)

c) increases rolling resistance and so shortens range slightly while increasing the average battery discharge level. That means your batteries will die a little earlier. But not by much.

d) depending on the amount you choose to reduce the pressures the ride height and ground clearance is reduced slightly as well.  This may or not matter to you.

e) improves ride, increases comfort, helps prevent shocks and vibration causing spastic problems.

f) can make powerchair harder to steer (esp. if rear drive) if you lower pressure in front casters by much (especially if programmed badly as most powerchairs seem to be!)

g) on a car or bike can cause tyre overheating. Not exactly an issue in a wheelchair!

 

Advantages of over inflating your tyres? Non. And can be dangerous too!

So what is the CORRECT pressure for your power wheelchairs tyres? Well its the one that best fits YOUR set of REQUIREMENTS and compromises. 

You have to choose between Comfort, Traction, Wear Rate, "Handling" or "Steering" in a chair, and consider how important ride height is and any other effects such as caster flutter. That usually gets worse with the pressure too high and improves as it is lowered within reason. The correct pressure is the one that fits your own preferences based on all of the above.  And occasionally (like today!) based on the weather!

Going to the pub in the snow?  (as I am in a minute!) I would temporarily drop mine down from say 30 to 15 PSI on a normal powerchair.  As it helps slightly with grip on snow. If I do get stuck I would drop them down even more! Anything that may help in fact rather than be stuck.  But wouldn't leave them that low once back home again.  In any case I found a better cure to this problem altogether! here

Going a long way today? Smooth surfaces? Save battery power and inflate them to the "recommended" pressures. 

For E.G. if you are having problems with spasm (spasticity), or whatever feel free to reduce the pressures until one or some of the downsides above begin to bother you more than the improvement in ride comfort!  Lower the pressures to the point where the types LOOK as if they are a bit low! Don't worry about it just try it! 

With current "state of the art" powerchair design, we do NEED more help! The world is not flat!  Everything in life is a compromise!  I don't know your chair, your issues, or your preferences. The only way is to test and see.  The correct pressure is the ones that perform best for your purposes. If you let some air out and cant tell, then let out more until you can. Try it. If you go too far then you will be able to feel a squishy soft ride and it will steer badly.

NOTE!

On a mid wheel drive chair or 6 wheel powerchair much of this doesn't apply obviously since the 4 caster wheels will just take the weight and you will get less traction as your centre wheels barely touch the ground...  And comfort or traction in snow will be worse. Another reason I dislike these types of powerchairs.


 

Menu:

Detailed PowerChair Only Menu

Related:

Powerchair Tyre Pressures  What should they be and why?

Tyre Weld Aerosol Punctures. We just love those! At least get et a can of tyre repair foam today!

Puncture Proof Tyres I mean real puncture proof, like the military use. NOT solid, foam filled, inserts or and of the other  "mobility solutions" that jar your spine every few feet outdoors. There are better ways.

Powerchair Tyres
A page discussing the types of powerchair tyres we have, can get, and which are best and why. Advantages and disadvantages of each type. So you know what to look for or to swap over to!

Powerchair Tyres Solids or Pneumatic?
Advantages and disadvantages of each type
. Which should you fit?

Run Flat Tyres for your car or van.

 

 

 

 

 

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