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Clearly, on average, cars are being used on fewer journeys of late, and it has been pretty wet. And some folks may have snow and salt to deal with... My guess would be there will be a higher likelyhood of various stuff seizing up, on many cars, than we'd usually see, not just drum brakes on those still fitted with them....

A disk conversion is appealing, but out of my price bracket! Also, maybe because I use the car at least every other day, my drums seem fine - so far...

Tell your insurer though - they should give you a discount for 'adding safety'! :)
It could be the premium increases. The cars ESP is set up to work with the brakes the car was homologated with. Add more braking power and then get into a panic braking situation and the pulses sent to the rear brakes may create an over braked situation...... After all disc brakes generally increase the braking depending on the pedal pressure and the pulses sent by the ESP when it gets called into action.

I would imagine the brake drums are made from poor material. Perhaps it rusts quickly. Supposition of course.
There is very little to service that will prevent the binding some are experiencing. We can clean or sand the shoes and shoe edges and clean up the inner drum faces but if it’s a poor material it will rust up again almost overnight.
I suspect having lots of play in the handbrake and not applying said handbrake is what most will have to do.
Which in my humble means the set up is simply not fit for purpose.
 

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Well, one can dream about lower insurance...... :)

Would a pukka kit not include re-calibrated hydraulic valving to ensure the rears disks don't lock too easily (or indeed, to ensure they get enough hydraulic pressure to be effective)?

As I said somewhere, while binding may well be down to the shoes sticking to the drums, could it (possibly) be in some cases, the handbrake cable sticking at the brake end, the internal lever sticking, or weak/bad batch of springs, and maybe other reasons?... I haven't yet read any clear reports about what was found when the sticking drum brakes were opened up and inspected.... I'm just trying to keep an open mind on the issue....
 

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Blimey even cheap Aygos have discs on the rear these days.
Not according to Toyota's spec sheets they don't. Rear discs don't come on any of the Aygo's. They become standard on the Yaris upwards.

There's nothing wrong with a well designed front disc / rear drum set-up for road cars. Don't forget all the older cars that were considered sports saloons and hot hatches :-
Opel Manta, Astra & Kadett GTE Mk 1 & 2, Vauxhall Chevette HS, Escort Mexico, Escort Twincam, RS1600, RS2000, Vauxhall Magnum, Avenger Tiger, BMW 2002, Some quicker than the Up GTi, some on a par, and some close behind in performance.
As I've said above, I've had no trouble with sticky rear brakes whatsoever, through 2 x High Up 75bhp, 2 x Tsi's, and a Gti, all sold at 3 years old, but with a cumulative 90,000 miles.
It's not clear whether the issue is on 3 year & older cars, and whether the cars with issues have ever had their rear drums / brake shoes changed.
Because I've not had this problem, I can't even say that the materials used are crap, or the design is poor.
Would like to have some more detail as to age of cars that have suffered, mileages etc.
 

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Well, one can dream about lower insurance...... :)

Would a pukka kit not include re-calibrated hydraulic valving to ensure the rears disks don't lock too easily (or indeed, to ensure they get enough hydraulic pressure to be effective)?

As I said somewhere, while binding may well be down to the shoes sticking to the drums, could it (possibly) be in some cases, the handbrake cable sticking at the brake end, the internal lever sticking, or weak/bad batch of springs, and maybe other reasons?... I haven't yet read any clear reports about what was found when the sticking drum brakes were opened up and inspected.... I'm just trying to keep an open mind on the issue....
It has to be the shoes sticking. You would not get that typical bang from a sticking cable.
Any kit cannot have modified valuing to suit the pulses sent by the ESPs brain. We can valve the pressures from the master cylinder as that is a constant where the ESPs pressures depend on how far the sensors tell it the car is out of control.
By replacing drums with discs we are effectively throwing away what the VW engineers designed and throwing away the parameters they engineered in.
As an extreme.
Say I’m driving really hard. Going downhill into a tight left hander too fast so hit the brakes. ESP sends a pulse to the rear inside wheel which then locks up because the power pulse was fine for weedy drums but to much for a disc and calipers ...

Bit extreme maybe but it is possible.

When racing motorcycles we used to increase the bore on the master cylinders to give far more braking power with more feel. A set up like we loved on track would be dangerous on the road. Yes far more power but extremely unforgiving,
 

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Not according to Toyota's spec sheets they don't. Rear discs don't come on any of the Aygo's. They become standard on the Yaris upwards.

There's nothing wrong with a well designed front disc / rear drum set-up for road cars. Don't forget all the older cars that were considered sports saloons and hot hatches :-
Opel Manta, Astra & Kadett GTE Mk 1 & 2, Vauxhall Chevette HS, Escort Mexico, Escort Twincam, RS1600, RS2000, Vauxhall Magnum, Avenger Tiger, BMW 2002, Some quicker than the Up GTi, some on a par, and some close behind in performance.
As I've said above, I've had no trouble with sticky rear brakes whatsoever, through 2 x High Up 75bhp, 2 x Tsi's, and a Gti, all sold at 3 years old, but with a cumulative 90,000 miles.
It's not clear whether the issue is on 3 year & older cars, and whether the cars with issues have ever had their rear drums / brake shoes changed.
Because I've not had this problem, I can't even say that the materials used are crap, or the design is poor.
Would like to have some more detail as to age of cars that have suffered, mileages etc.
OK Picky. 😂😂 We have a 2012 Toyota IQ here and that has rear discs not drums. Drums are out of date junk. Which is why so many dislike them.
 

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Late in here. Stuck on drums are common. I haven't had it yet on the UP! but both my Triumphs have rear drums, and in winter, the drums stick on (always parked with the hand brake off), just drive off, bit of a clunk, all done. Next time you brake the contact point is cleaned, no harm done ! 😉
 

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Not according to Toyota's spec sheets they don't. Rear discs don't come on any of the Aygo's. They become standard on the Yaris upwards.

There's nothing wrong with a well designed front disc / rear drum set-up for road cars. Don't forget all the older cars that were considered sports saloons and hot hatches :-
Opel Manta, Astra & Kadett GTE Mk 1 & 2, Vauxhall Chevette HS, Escort Mexico, Escort Twincam, RS1600, RS2000, Vauxhall Magnum, Avenger Tiger, BMW 2002, Some quicker than the Up GTi, some on a par, and some close behind in performance.
As I've said above, I've had no trouble with sticky rear brakes whatsoever, through 2 x High Up 75bhp, 2 x Tsi's, and a Gti, all sold at 3 years old, but with a cumulative 90,000 miles.
It's not clear whether the issue is on 3 year & older cars, and whether the cars with issues have ever had their rear drums / brake shoes changed.
Because I've not had this problem, I can't even say that the materials used are crap, or the design is poor.
Would like to have some more detail as to age of cars that have suffered, mileages etc.
Agree, nothing wrong with drums on the back of such a small car. The front discs are shared with Audi A3s AFAIK so well braked up front, and don't forget most braking effort is through the front anyway.

Mine sticks. Never liked driving and just letting them twang off. If I can, I reverse the car a touch and they come off without the noise.
 
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I agree, I also think that part of the problem is that over the past twenty / twenty-five years, almost all of the cars that are bigger & relatively more expensive than an Up / Aygo etc have had rear discs, so people forget that part of the maintenance involves cleaning out brake drums, like almost all of the older cars, and so they get caked up with dust and that contributes to the shoes sticking on.
 
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