mx5cartalk.com

Hi guys,

I went on a bit of a blitz on my brakes when I discovered one of the rear slider pins had seized solid. I ended up doing full rebuilds on all calipers, new pads (QFM HPX all-round), HEL Performance braided brake lines and bled the whole system with fresh Castrol Response DOT4.

I (think...) I have an issue with the brake pedal now. I feel initial bite is improved (as expected) but pedal travel seems to be reduced. I'm hitting a hard stop in the pedal when braking HARD and only occasionally triggering ABS. I don't recall ever hitting this stop before I did this work.

Critical information:
1. System is bled correctly
2. Handbrake adjustment at caliper is correct
3. Rotors are within serviceable spec and good condition
4. Pads have endured the correct bedding-in procedure
5. No fluid leaks in the system


Any thoughts? I'll double-check free-play in the pedal tonight but I didn't think that would need adjustment.

Thanks!

The less pedal travel then better. What is the problem? You are using less pedal but getting more braking power.

The problem is you now have a good pedal compared to what you had before.

The fluid probably hadn't been changed for a while, and the pads were worn, that all increases the travel you would have had before doing the work.

nhouison wrote:Critical information:
2. Handbrake adjustment at caliper is correct

Appreciate you indicate this was done correctly, but was the handbrake cable slackened right off, or disconnected from the calipers? If not, it should be before adjusting for handbrake at the caliper:
See toward end page 1 & start of page 2:
viewtopic.php?f=30&t=66092
viewtopic.php?f=30&t=66092&start=15
See note at bottom of page: http://www.miata.net/garage/ebrake/index.html

When I say hard stop I mean there is something mechanical stopping my pedal from going any further, not that the system has reached its limit and pressure is stopping the pedal from moving further.

@93_clubman - yep, definitely adjusted the rears properly.

Perhaps I just didn't notice the stop before... It's the only 5 I've really dríven so I'm learning new things everyday.

nhouison wrote:When I say hard stop I mean there is something mechanical stopping my pedal from going any further, not that the system has reached its limit and pressure is stopping the pedal from moving further.

so it is hitting the floor?

No, it's being stopped probably 3" from the floor.