Omega Brake Force Distribution

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Sun 18 Jan 2004 17:57
Omega Brake Force Distribution - PST
I took my 2001 Omega 3.0 for its first MOT last week. It passed but on the accompanying tick list sheet they give you I was intrigued with the brake test figures. They don't give units of measurement but the fronts were 450/420, rears 220/220 and handbrake 270/280.

Should the fact that the fronts are not equal be cause for concern? Presumably this could cause pulling during heavy braking or is the difference to small? And why should they be different - pads have been changed at the same time.

Curiousity really but would be interested to hear your comments.

Paul
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Tue 20 Jan 2004 00:29
Omega Brake Force Distribution - geoff C
Figures are maximum forces in kg. at about 20% wheel to roller slip. (On a roller brake tester)

Side to side differences reflect weight differences on wheels (eg. driver). Up to 40kg difference in measured peak brake force is allowed. Peak force depends only on weight on each wheel and tyre/roller friction unless a brake is seriously faulty.

The test also measures the side-to-side difference as the braking is increased and this must not exceed 25% at any stage.

Front-to-rear difference is expected. Front is heavier and rear-to-front weight transfer is caused by braking (on the road, not on the tester), so fronts have to do more work. If the car was fully loaded during the test the rear figure would be higher.

The overall brake efficiency percentage is taken as the total brake force on all wheels divided by the total weight on all wheels x 100. This must be greater than 50%, but should approach 100% on most modern cars.
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Tue 20 Jan 2004 18:55
Omega Brake Force Distribution - mgk luton beds
load sensing valve will hold rears off so dep on weight but hand brake has little shoe inside disc and will be higher
all figures look great to me
fronts are ok diff being grip to rollers /rollers to tyres
/tyres press/friction materal on pads/the list is endless but up to 25%imbalance is allowed so if one side is200 then the other could be 150to250 and would still pass (with an advice note to say that they are on limit)
ex mot tester
ex vaux tech
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Wed 21 Jan 2004 00:36
Omega Brake Force Distribution - PST
Thanks Guys

Interesting answers and something else I've learnt!

Paul
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