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Alright guys, I've done my search on the forum but couldn't find the answer that I want (Search is not my friend this time)

I've got a NB8A on 77kkms with OEM rotors (on standard nothing special pads). 16*7 rims on Toyo Proxies4 205/45 tyres.

Recently did a few rounds at Galston Gorge and Wiseman's Ferry area and found the brakes to be:

- Too mushy
- Doesn't stop fast enough and
- The amount of 'space' that I can push the brake paddle down before it reaches the bottom to deteriorate significantly (not that i would ever go to the bottom cause it'll just lock)

So... what I can do to fix it? (going from the most economical fix to the least...)

- Read about bleeding brakes - no idea what it means and how to do it.
- Maybe I need to change the pads? (If so, I would like something that lasts a decent amount of time and doesn't squeak for street use only)
- Read about the MC cylinder and upgrading the brake lines as well - not sure it's what i should do for what i need.


A little help please?

Bleed the brakes and then fit a Master Cylinder Brace, cheap and effective and it will provide you with a solid platform from which to work.
Greg.

When was the last time you had the brake fluid flushed and replaced?

Guran wrote:When was the last time you had the brake fluid flushed and replaced?

Agree with Guran, flush and replace the fluid.
Also get the brakes checked out and adjusted correctly

If you don't know what or how to check, adjust or bleed your brakes, pay someone who does.
Brakes are not something to 'have a go at'

IMHO, if all you are doing is spirited driving on the road, mods to the brakes are not necessary.

no idea when's the last time the fluid has been changed but I'm due for a service soon so I'll def let them know to check it out.

Any suggestions on a particular type / brand of fluid to use?

If changing the fluid doesn't work, what's next?

search for dot 3

I use Castrol Response Super DOT 4 or Nulon XBF Super DOT 4. Both have 286C dry 184C wet boiling points. Both cost around $10 per bottle. I flush it every six months including about 6-8 trackdays. It'd last at least a year with more sympathetic use. Brake fluids should be replaced after no more than two years. It goes off, absorbs humidity and causes brake fade.

Elf HTX115 is better again (290C dry 200C wet) but costs a lot more too. Next step up is Lucas TRW GP600 or PBR BF-600 (312C dry 204C wet). Premium stuff is Motul RBF600 (312C dry 216C wet). You're looking at around $60 a bottle for the Motul stuff. Great for the track but overkill for a street car.

Do not be tempted to use Castrol SRF in an MX-5. CT warned me off that stuff. Apparently the MX-5 brake system is not compatible with these silicon ester brake fluids.

You'll need two bottles to flush and refill the brake fluid.

Guran wrote:I use Castrol Response Super DOT 4

I use this as well, never had it fade on the track no matter how hard I try.

Since the symptoms described is a spongy pedel, I'd bet on replacing the brake fluid 1st. Especially if it is unknown what the current age of it is. It could be a safe bet that with only 77,000km on the clock, that it is the original fluid from new.

Getting the car into garage this Thursday and will test it out on the weekend - thanks guys

Better get this 'fixed' before the September 12th run...

Check for sticky caliper slider pins too, may mean that only 1 pad is pushing on 1 side of the disc.

Happened on my car, went from gear brakes, to crap brakes with spongy pedal in 3 weeks...

Rebuilt the calipers, swapped to hawk HP+ pads, added stainless lines and now can do 1.3G under brakes

Alright, got the car back from I.S. Motor-racing last week from servicing and they've suggested that I do change the brake fluid at the next service when my pads are due as well (so that i don't get charged double labour).

So here's the question - what kind of pads would suit me?

- Daily drive + occasional spirited driving (need better braking power than OEM)
- No squeak please. Don't like annoying other people on the road
- Prefer it to lasts 'a while'

Thanks for your thoughts

I use RB74's?? I think on Malibu and I really like them. Really the MX-5 has good brakes to start with, so standard stuff would be more than adequate for the type of driving you do.

I really believe all you need is a good flush and a rear calliper/handbrake adjustment if it has the screw adjuster, and the thing will be great.

Jules

BadBong wrote:Alright, got the car back from I.S. Motor-racing last week from servicing and they've suggested that I do change the brake fluid at the next service when my pads are due as well (so that i don't get charged double labour).

So here's the question - what kind of pads would suit me?

- Daily drive + occasional spirited driving (need better braking power than OEM)
- No squeak please. Don't like annoying other people on the road
- Prefer it to lasts 'a while'

Thanks for your thoughts

Are you, or perhaps I should say, I.S Motor racing, serious?! You're not going to get your brakes bled because of the labour cost? Mate, ABS brakes would change the fluid for you for only about $60 or $70. You don't have to change fluid when you change pads, so there would be no "double labour" charges involved in doing that now rather than waiting until the pads need changing. The more often the fluid is changed, the better. I change mine at least a couple of times a year, more frequently depending on track time - much cheaper and easier than replacing rusted brake components, or the front of my car which wouldn't stop because of poor brakes...

As for brake pads, the OEM (Sumitomo labelled?) ones are very good, especially if you're only using your car on the road. How do you know that your current pads are OEM? They also are better than many so called 'performance pads' which people buy for the track. If you think you need better braking than what you have now, start with changing the brake fluid and see how that goes. At the moment I'm using Hawk Performance Ceramic pads which work well on the road and track, purchased from MX5 Mania.

I agree with jules. Flush the brake fluid and change the pads. For your usage, nothing fancy is required for either. I don't expect you will be disappointed with Castrol Response Super and OEM pads. You should be changing the brake fluid at least every two years regardless of use - six monthly is ideal. DIY is easy and cost is about $20 each time (two bottles fluid).