Hi all

Just received the dreaded phone call from the garage that the faithful Octy had failed it's MOT. So, now waiting on a new NSR caliper & discs being fitted. However, one of the advisories on the MOT was for "brake imbalance", clearly only slight or it would have failed on this too but what I wondered was could brake imbalance be mistaken for a wheel imbalance problem??

It may sound a silly question but I haven't noticed any judder, shaking or wheel pulling to left or right; I have noticed that when I get up to around 70 -75 mph (allegedly!!) I get a bit of vibration through the steering wheel. There is absolutely no problem at lower speeds & brakes seem to work absolutely fine.

Any comments??

Surely that's why there replacing caliper ?

That's what I thought too cntuning, but the caliper is being replaced due to hand brake issues. After being stripped & cleaned it improved things for a few months & then it was as if the hand brake lever was attached to nothing at all, had to pull it up about 8 or 9 notches & obviously only the osr was engaging properly.

Just wondered if you could have brake imbalance front or rear or corner to corner?? Apologies for dumb question, just trying to learn a thing or too!!

is it front or rear brake imbalance that they have advised.

I think front brake imbalance you are allowed 10%

Yeah it's either front or rear

Normally a sticking caliper take a pic of advisory

One of my rear (octy vRS) calipers is sticking. I am wondering if its a really poor design as I have heard about a lot of failures. :(

I replaced one of my rears a few months ago too

Both of mine are playing up. Hand brake mechanism on near side is broken, and off side seizing.

Can you still buy green calipers from skoda...

I think if you buy calipers from skoda they come green, aftermarket ones are just zinc coated

I change my rear calipers about a month ago due to one of them sticking and the other not working, but as for the braking imbalance bleed the whole system and that should sort it

http://www.ebay.co.uk/itm/Skoda-Octavia-1U2-1996-2009-RS-LEFT-NS-REAR-brake-caliper-GREEN-new-/160877110765?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Model%3AOctavia|Cars+Type%3ARS+1.8+T&hash=item257505e5ed

http://www.ebay.co.uk/itm/Skoda-Octavia-1U2-1996-2009-RS-RIGHT-OS-REAR-brake-caliper-GREEN-new-/150893393155?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Model%3AOctavia|Cars+Type%3ARS+1.8+T&hash=item2321f27503

Cheapest place Ive seen.

Brake balance is usually on the front and you're allowed 20%. If it was near 20% you'd already know about it as it wouldn't brake in a straight line. AS has been said, write exactly what is on the sheet.

Brake imbalance is measured on the steered axle only. On the roller brake tester (RBT), both front wheels are spun together, the brake is applied to a point well before the wheels lock and the readings recorded, you may get a reading of 200kg on one side and 180kg on the other. This gives a 20kg difference which is 10% of the larger reading which gives an imbalance figure of 10%. The maximum allowable imbalance is 25%.

You can't fail a non steered axle on imbalance.

When testing the rear brakes on the RBT as well as measuring the efforts from each wheel for the service and parking brake (if applicable) the rate of increase of the brake effort is checked on applying the brake and the rate of decrease when releasing the brake, both brakes should increase/decrease at roughly the same rate.

Ok, got MOT receipt back today & the refusal slip states this "Brakes Advisories: RBT Front Brake Imbalance: 15%"

Then underneath an explanation which says"Front brakes only just et the front brake imbalance requirements. it would appear the braking system requires adjustment or repair."

The other advisories were for a deteriorated front suspension bush that didn't result in excessive movment & tyre close to the legal limit.

However on the retest it only has the advisories about the bush & the tyre & NOT the brake imbalance.

Could the work done on the rear caliper have sorted this & would they have tested the RBT on the front again.

The car drives absolutely fine, brakes in a straight line & there is no sign of pull to either side??

The work on the rear caliper won't have done it, but it's possible that even just bleeding the brakes may have made a world of difference.

http://www.ebay.co.uk/itm/Skoda-Octavia-1U2-1996-2009-RS-LEFT-NS-REAR-brake-caliper-GREEN-new-/160877110765?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Model%3AOctavia|Cars+Type%3ARS+1.8+T&hash=item257505e5ed

http://www.ebay.co.uk/itm/Skoda-Octavia-1U2-1996-2009-RS-RIGHT-OS-REAR-brake-caliper-GREEN-new-/150893393155?pt=UK_CarsParts_Vehicles_CarParts_SM&fits=Model%3AOctavia|Cars+Type%3ARS+1.8+T&hash=item2321f27503

Cheapest place Ive seen.

I have one if these on the driver side. Great job and it's a genuine Lucas one, with the lucas part filed off.