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Posted by: jesiv Aug 17 2013, 07:01 PM

Several weeks ago I replaced all the rotors, pads and flushed the brake fluid. I used the Motive pressurized brake bleeder using two quarts of fluid to really flush the system. The emergency brake works perfectly and the car stops great. However I can't get the brakes to lock up. I have brand new eagle GTs 195.65.15 with obviously lots of tread. I am wondering if something is not quite right since I can't lock the wheels. The brake pedal is hard but the won't lock. Should I be concerned? The pads have several hundred miles now.

Should I consider not locking up a good thing or do I need to consider this a harbinger of failures to come...

Thanks for your thoughts

Regards

James

Posted by: kg6dxn Aug 17 2013, 07:25 PM

You need to bed the pads per Eric Shea's directions...

Posted by: tracks914 Aug 17 2013, 08:04 PM

First find some gravel, might be hard to do in California, and try locking them up there. If they won't then you have problems. If they do then see above post.

Posted by: jesiv Aug 17 2013, 08:51 PM

If I do what sort of problem would I have?

Regards

James

Posted by: solex Aug 17 2013, 09:13 PM

Do a quick search your brakes should not lock up. If they do than you are no longer in control.

Posted by: jesiv Aug 17 2013, 09:34 PM

I don't mean that I want them to! I just want toknow that at some point they will. My 1971 914-6 did, my 1976 2.0 did and this one did until I replaced the wheels, tires, rotors and pads.

I am researching "brake bedding" but have not found Eric's thread. So anyone knows the link please post it

Regards

James

Posted by: FourBlades Aug 17 2013, 10:07 PM

I had the same problem after replacing my brakes with new parts until I bedded mine in using Eric's instructions:

http://www.pmbperformance.com/bedin.html

I can lock them now using pretty heavy foot pressure.

John

Posted by: Trekkor Aug 17 2013, 10:08 PM

914's are not equipped with anti-lock brakes.
Yes, they should lock up if you apply very hard pedal pressure.

Bedding is helpful, but not mandatory.

An aggressive pad will alter the feel and make locking the wheel easier.

This is how I know when my car has enough brakes.
Can I lock the wheels at will? If no, you need more brakes.


It's been said that a properly maintained stock 914 brake system is acceptable for any street application, regardless of engine conversion.


KT

Posted by: Andyrew Aug 17 2013, 10:43 PM

At lower speeds I dont think you have enough pressure with the stock brakes and master cylinder to lock the brakes up unless you really jab the brakes really hard violently and quickly. Basically giving the car no time to transition weight to assist braking.

Posted by: solex Aug 17 2013, 11:01 PM

Really they should not lock up unless you are doing it on purpose, they are very balanced stock system. Here is the link http://www.pmbperformance.com/bedin.html

Posted by: jesiv Aug 18 2013, 09:58 AM

I am trying to lock them up to confirm they are working properly. I think the issue is bedding. I got a higher performance pad from Rich at HPH and thought I had bedded them properly but obviously I have not. I will try again following Eric's recommendations. Hopefully by the end of the day I have brakes!

Regards

James

Posted by: r3dplanet Aug 18 2013, 10:07 AM

Watching with great interest. I replaced all of my components with new parts last year and have the exact same problem. Even after repeatedly following the break-in instructions. I really dislike how the brakes just feel suggestive instead of dead on positive.

Posted by: mepstein Aug 18 2013, 10:26 AM

Are you guys using 19mm mc's? 17mm is more powerful. Not a ton but there is a difference. Yes, the pedal can be slightly softer but everything is a trade off. Make sure your sqishy pedal isn't bad bushings or a rusty pedal area.

We used to talk about the firm/soft brake issue with the brakes on mt. and road bikes. Firm brakes feel good on a test drive. Soft but effective brakes feel good and are easier to modulate after a couple hours riding when your hands are tired and sore.

Posted by: Andyrew Aug 18 2013, 10:47 AM

High performance pads need to be beaded in with LOTS of heat and possibly multiple applications.

The rotors gets coated with the pad material and after it cools then the rotors have a small layer that gives them an incredible bite. You cant touch the brakes after you get them blisteringly hot though, and you have to let them cool down. I like moving the car a foot every 10 minutes to let the rotors cool evenly after getting the car back home.


Stock street pads dont need this but a small application does help.

Posted by: stugray Aug 18 2013, 08:30 PM

Just drove my hanger queen for her first few "laps" after 3 years on jackstands and new pads.

NO PROBLEM locking them up with just a quick jab on the brakes.

I was even trying to play it cool tooling around the neighboorhood , until the brake test.

Good news is: I can chirp the tires in first & second or jamming the brakes!

safety checks complete. ( funny I just did the same test with my trailer today, and they DONT lock, but 'work')

Stu

Posted by: jesiv Aug 18 2013, 08:49 PM

Well I try to do the bedding but it is hard to in the Bay Area. I didn't do it early am. However a big improvement. I will get up early next weekend and see if I can finish the job. In my opinion still not 100%. Any way the new tread on the eagle GTs is preventing lockup? Meaning they are gripping instead of sliding?

Regards

James

Posted by: stugray Aug 18 2013, 09:10 PM

I have had brand new Eagle GTs with the stickers still On.
They lock even easier when new.

You should have zero trouble locking the brakes.
You should be able to lock them at 10 MPH.

No brake pad bedding required.
You have a problem.

Stu

Posted by: Eric_Shea Aug 18 2013, 09:24 PM

Anything under a narrow body car should lock up. Just bed them again and make sure your venting clearance is set properly first.

Your rotors should have a grayish/blue hue to them and they should be stinking hot. Remember not to stop afterward until they have a chance to cool down. Get on the 5 and drive to SJ and back.

You didn't mention what pads you're using. For years people have been steered toward semi-metallic pads. Low dust no noise... no stoppy. What pads did you end up with?

A good set of organic pads like Pagid or Textar should do the trick if they are bedded properly, or spend a few dollars more and get Porterfield R4S compound. All of the above should be noise free and relatively low on dust if they are setup properly.

And echoing whats been said herein, you should be able to modulate your pedal to the point of locking easily and evenly. I do understand the desire to at least get them to that point, and you should be able to accomplish that after you really bed them properly but... you get the picture.