Anyone had issues with handbrake caliper removal?
Discussion
Sorry - bit random - but it stopped me fitting some new disks to the Rapide as the bolts holding both handbrake calipers on were super tight and also when turned were pulling out the floating sleeve they sit in. Snapping it would have meant missing a ferry on Weds so caution meant a failed bit of maintenance!
Does anyone know if this is a common issue (calipers were off 2 years ago for new pads and were definitely greased on refitting by the Indie - you can see the grease). Maybe its just Locktite but the risk in snappingt he bolt was just too great.
Is there maybe a refurb kit that comes with the rubber boots (hence why a bit of heat couldn't be applied).
Or tell me to leg it to Practical Classics forum ;-)
Finally anyone know why the OEM Brembo pads have a bit cut off the back to reduce pad area???
Cheers
Does anyone know if this is a common issue (calipers were off 2 years ago for new pads and were definitely greased on refitting by the Indie - you can see the grease). Maybe its just Locktite but the risk in snappingt he bolt was just too great.
Is there maybe a refurb kit that comes with the rubber boots (hence why a bit of heat couldn't be applied).
Or tell me to leg it to Practical Classics forum ;-)
Finally anyone know why the OEM Brembo pads have a bit cut off the back to reduce pad area???
Cheers
The chamfering of the brake pad is just to try and reduce noise from brakes.
I had quite a wrestle taking my V8V handbrake calliper off. Just required lots of elbow grease and the right tool with plenty of leverage. Assess was easier with the wheel arch liner and toe link out of the way which was required as I was removing the damper also.
I had quite a wrestle taking my V8V handbrake calliper off. Just required lots of elbow grease and the right tool with plenty of leverage. Assess was easier with the wheel arch liner and toe link out of the way which was required as I was removing the damper also.
Thanks guys & thanks GenieChaser.
I have a Foxwell scanner running actual AM diagnostic software so will checkout if that will roll the handbrake pads back to create room for the new disk. Ohh for the straightforward days of TVR and Ford Escort maintenance!
On the main (old) Brembo pads it isn't a chamfer; its a definite unused section of pad that is recessed - loses about 20% of the total usable pad area. Is that a way of managing front to rear brake bias do you think?
I have a Foxwell scanner running actual AM diagnostic software so will checkout if that will roll the handbrake pads back to create room for the new disk. Ohh for the straightforward days of TVR and Ford Escort maintenance!
On the main (old) Brembo pads it isn't a chamfer; its a definite unused section of pad that is recessed - loses about 20% of the total usable pad area. Is that a way of managing front to rear brake bias do you think?
Just changed my rear discs today (V8V) .....and split the handbrake caliper, wound it back as the new discs were thicker (used some long nose pliers), bled the brakes and all good with no AMDS in sight! Only sod was the disc retaining screw that stripped so hammered in an Allen key socket and out in came.....very satisfying
It was likely done to help eliminate brake squeal. The front OEM Pagid 4-2-2 pads squeal sometimes, and it's a big complaint people have of the OEM pads (also, dust and cost). The squeal is the result of buildup on the leading edge. Chamfering prevents buildup and eliminates the squeal. Typically, pads are chamfered on both the leading and trailing edges. Whoever did yours did a more drastic angle and only on the leading edge.
The chamfer can also create a smoother brake feel since it creates an angled contact between pad and rotor, rather than a perpendicular contact. It's possible that unchamfered pads can pulse or shimmy a little under hard braking.
Here's a pic of a Porterfield R4-S and Porterfield R4.
The R4 (the new one) is not chamfered. It's a track pad so friction surface area is more important than noise.
The R4-S (the used one) is chamfered. Off the top of my head, I think it was a ~30% reduction in friction surface area. In normal-to-spirited driving, the R4-S is perfectly fine. If you drive on track, I would suggest getting something more aggressive than the R4-S because it does become a big limitation. But in normal driving, it's fantastic (no dust, no noise, and less costly than OEM). It's what I use on my red V8V. (I've written about this and other pads quite a bit, and even have a video on YouTube covering a few different pads.)
The chamfer of the R4-S is the same on both sides, and here's showing those two pads again, but from the side:
Both of these are 4-piston front caliper pads. The pads for 6-piston front calipers are much, much larger. Here's the Porterfield R4-S for the 6-piston and 4-piston calipers...
The chamfer can also create a smoother brake feel since it creates an angled contact between pad and rotor, rather than a perpendicular contact. It's possible that unchamfered pads can pulse or shimmy a little under hard braking.
Here's a pic of a Porterfield R4-S and Porterfield R4.
The R4 (the new one) is not chamfered. It's a track pad so friction surface area is more important than noise.
The R4-S (the used one) is chamfered. Off the top of my head, I think it was a ~30% reduction in friction surface area. In normal-to-spirited driving, the R4-S is perfectly fine. If you drive on track, I would suggest getting something more aggressive than the R4-S because it does become a big limitation. But in normal driving, it's fantastic (no dust, no noise, and less costly than OEM). It's what I use on my red V8V. (I've written about this and other pads quite a bit, and even have a video on YouTube covering a few different pads.)
The chamfer of the R4-S is the same on both sides, and here's showing those two pads again, but from the side:
Both of these are 4-piston front caliper pads. The pads for 6-piston front calipers are much, much larger. Here's the Porterfield R4-S for the 6-piston and 4-piston calipers...
Rich it was Porterfield R4-S I put on it after your recommendation. They had no chamfer at all! This for the 4 pot rears - I think the Rapide has bigger brakes than a DB9 and Vantage... Definitely no chamfer and no squeal either as of now 
I need to source similar 6 pot front pads for a May fitment. Wonder if they will have a chamfer (kind of hope they will) . Its all a Brembo made caliper that is a common AMG fitment too I believe
I need to source similar 6 pot front pads for a May fitment. Wonder if they will have a chamfer (kind of hope they will) . Its all a Brembo made caliper that is a common AMG fitment too I believe
Ken Figenus said:
Rich it was Porterfield R4-S I put on it after your recommendation. They had no chamfer at all! This for the 4 pot rears - I think the Rapide has bigger brakes than a DB9 and Vantage... Definitely no chamfer and no squeal either as of now
I need to source similar 6 pot front pads for a May fitment. Wonder if they will have a chamfer (kind of hope they will) . Its all a Brembo made caliper that is a common AMG fitment too I believe
The dozens that I've seen have all been chamfered. Might be the vendor there not wanting that? I'm not sure why they wouldn't, though.I need to source similar 6 pot front pads for a May fitment. Wonder if they will have a chamfer (kind of hope they will) . Its all a Brembo made caliper that is a common AMG fitment too I believe
I think their s type jag handbrake calipers, try euro car parts , they do loads of "fitting kits" for various calipers, you never know the am dealer might sell them, ive often been suprised by the reasonable price of some stuff from am, we always assume everything is going to be over priced.
@Dungman did you find the bellows for the handbrake sliders? Mine are just missing from both upper sliders - just disappeared!! Am writing to Frentech to see if they can help, but if you tracked the right kit down it'd be great to know.
Also struggling with the pins and spring plate, they are rusty but function fine so I may just clean them up. Astonbits quoting £30+VAT for the pins per PAIR and £30+VAT EACH for the spring plates.
Also struggling with the pins and spring plate, they are rusty but function fine so I may just clean them up. Astonbits quoting £30+VAT for the pins per PAIR and £30+VAT EACH for the spring plates.
For future reference, by working with the excellent Dave from Frentech, we have found the gaiter boots for the hand brake sliders. They are;
Part number 51837 from Frentech via eBay (they aren't on eBay but Frentech can supply them if you contact them via eBay). £3.49 each plus posting.
The pins are very similar to the Range Rover Sport (2005-2013) Front Brake Pad fitting kit, but they don't fit quite so well so I'm re-using the old pins. They have a slightly shorter reduced diameter engagement piece machined on the end of the pin although a tiny drill out of the pin receiving hole in the caliper by 2-3mm depth to 6mm diameter would mean they fit, if you are desperate.
Part number 51837 from Frentech via eBay (they aren't on eBay but Frentech can supply them if you contact them via eBay). £3.49 each plus posting.
The pins are very similar to the Range Rover Sport (2005-2013) Front Brake Pad fitting kit, but they don't fit quite so well so I'm re-using the old pins. They have a slightly shorter reduced diameter engagement piece machined on the end of the pin although a tiny drill out of the pin receiving hole in the caliper by 2-3mm depth to 6mm diameter would mean they fit, if you are desperate.
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