Drum to disc

[Doug G]

What is involved to change the existing drum (front and rear) to discs"?

[Tim]

Cubic money, especially if you want to convert the rear to disk.

The simplest method of converting only the front to disk would require sourcing a set of 8.4" disk brake front hubs, including CV joints, from a late model Mini and bolting them on. This can be quite expensive as they are heavy, which pushes the freight up. Most secondhand ones will require reconditioning which pushes the price up to close to what you'd pay for new ones. You also need to fit smaller rear slave cylinders or you will probably find that the rear wheels lock up too easily.

Converting the rear to disk requires either some very clever engineering to modify the brakes off something else, or buying some KAD rear disks (or something similar). I see Minimania list the KAD kit for $1,695.00. The only improvement that they'll give you is that they don't require adjusting.

I put metro turbo 4 pots on mine, but they are overkill, standard Mini ones (as used on late model Mokes) would have been fine. I think its a modification thats well worth doing, it does improve the braking and they need much less maintenance.

Tim

[PJ]

I put metro turbo 4 pots on mine, but they are overkill, standard Mini ones (as used on late model Mokes) would have been fine.

Tim,

What makes you say the Metro 4-pots are overkill? I'm not very impressed by the standard, fully reconditioned, 8.4" 2-pots on mine and am planning to upgrade - but not decided how far to go.

I believe the 8.4" set-up was originally developed for the 1275GT with 12" wheels and low profile tyres so our 13" wheels with relatively high profile tyres will exert a greater braking torque. All things being equal (which they never are!) one would expect them to be less effective on a Moke than in their original application. Admittedly, on the plus side a Moke is not quite as heavy and has a slightly lower speed potential but this has to be set against the fact that the larger diameter and wider tyres on a Moke give it a larger contact patch and tyres have advanced over the last 30 years so it would be reasonable to assume that a Moke could use a more powerfull brake set-up than the basic 8.4".

If anyone out there has upgraded brakes, please let me know what you've got and what you think of them before I go out and waste my 'hard earned' on a totally OTT set-up.

PJ

[Tim]

PJ, I agree with you regarding the wheel diameter, I had Cooper S 7.5" disks on the previous Moke and they were really not worth the money. They weren't hugely better than well adjusted drums, and cost a packet.

The standard 8.4" setup seems to be regarded as perfectly adequate by most 13" wheel moke owners I know. The metro discs are the same diameter as the standard ones, so there is no gain there. But they are fitted with 4 pot calipers. I guess the calipers help a bit, but the standard ones seem to be pretty good. Against that is the penalty of unsprung weight and the negative effects that can have on ride and handling. The metro calipers and disks (which are ventilated so have a lot more metal in them) are heavy, really heavy, as are my sunraysia wheels and big chunky winter tyres. I upgraded the suspension at the same time that I fitted the new brakes, maybe I'm imagining it but but I feel that it would have been even better if I hadn't added all that extra weight.

As there are very few late model Minis and no Metros here I bought the whole kit from Minispares in the UK
[img:200:159]http://www.minispares.com/images/produc ... J4029A.jpg[/img]

Tim

[Dean]

I transplanted a secondhand standard 12" disc setup from a Mini on to one of my Mokes (13" 998cc Cali) and was really impressed with the improvement over the drums.
The only niggle I had was under heavy prolonged braking at motorway speeds. I felt the brakes faded a bit but I put this down to the fact the discs were old and really needed replacing but they were still miles better than the drums which faded at even low speeds. I was planning on fitting uprated discs and pads but never got round to it.
Dean

[Steve]

All interesting stuff guy's as I have calipers, disc & drives in poly bags awaiting cleaning up prior to fitting. I bought them as 'off a Metro' and they have been in the bags since February, I'll be replacing the disc's (dunno what size they are) should I so stand by for some dumb questions! ..

[PJ]

The metro calipers and disks (which are ventilated so have a lot more metal in them) are heavy, really heavy

2 piston caliper, standard 8.4" = 3.46 kg
4 piston Metro caliper = 3.48 kg
Minispares billet 4 piston caliper = 1.15 kg (that's the old alloy piston version - they now have stainless pistons and seals more suited to road use and are fractionally heavier)

You could lighten both your wallet and your unsprung weight in one easy move , or ask santa.

I don't know how much weight you'd save by ditching the vented discs and going for drilled and/or grooved non-vented ones, but I've heard that you won't really get mini brakes hot enough on road use to have a problem with disc heat (alloy calipers will help dissipated heat, anyway), and that the normally available vented discs are pretty well ineffective for cooling because they don't allow unimpeded airflow through the 'vanes' from the centre outwards. Make of that what you will.

Another issue, which I don't intend to (publicly) take a stance on (liability ) is the removal of the disc shields. Those in favour of removing them suggest that they restrict cooling, are unnecessary weight and point out that street motorcycles, which have even more exposed discs, don't have them. The other camp point out that BMC/BL would never fit unnecessary parts because of the cost and that they keep the wet off which causes lag, an argument countered by the suggestion that the discs are shielded inside the wheel rim, almost all of whatever small amount of water reaches the disc will be flung off by centrifugal force, and any drops that may hang on would be pushed into holes or grooves!

PJ

[Tim]

I'm amazed that they were able to build the standard calipers so heavy, the metro ones seem to have a large amount of excess metal on them. Unless an unlikely lottery windfall comes my way I'll be staying with the cast iron ones.

I don't have any shields, they didn't come in the kit and my old cooper s setup didn't have them either. I've only ever noticed an issue with wet brakes once, and that was as I drove out of a car wash.

Tim