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Old 05-14-2012, 06:06 AM   #1
Jonny042 OP
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Joined: Mar 2012
Oddometer: 71
Formula Brakes Fiasco - Fixed!!

Hello all, I posted the following to trialscentral last night and thought I should share it here as well:

I am posting this here in the hopes that it prevents someone else from the same frustration I went through... .and also to help dispel the myth that the Formula brakes are crap because they`re not, necessarily. But they are certainly getting a bad rap.

Let me start by saying I`ve been optimistic about these brakes from the beginning - I always though the AJP stuff was in need of an update and in particular hated the plastic lever bushes and the reach adjustment. So along comes the formula stuff with a proper monoblock caliper (current state of the art for racing, prevents caliper flex by eliminating the need to `split` the caliper into halves) and an ingenious reach adjustment that does with one thumbwheel (no tools!!) that used to need two threaded adjusters, a 10mm whrench, and an allen key. Also gone are the plastic lever bushings, replaced by a stainless steel pivot pin. Engineering wise there is a lot to like about these components, not to mention they are a bit lighter than even the latest and greatest AJP kit on my 2011.

So the brakes are trick, but they didn`t work right!! First impressions were good but it soon became clear that something is rotten in the province of Bologna.....sort of a `notchy` feel to the brakes. I started by taking apart the Master cylinder and found it to be `graunchy`` so took it apart, cleaned it up, and it improved it immensly, and also I found the pivot pin was dry as a bone from the factory and lubed it a bit. This certainly improved things a bit and my first couple of hours on the bike were happy ones, but by the second time I rode the bike I found the brake to be getting worse - poor feel, short on power, too much lever travel, etc. this was a few days ago and today I finally had some time today to fiddle and made up my mind to fix it once and for all.

I literally spent all afternoon completely disassembling the front brake caliper, cleaning it all up (an ALARMING amount of aluminum filings), polishing the bores, reassembling, took apart the m/c and cleaned it for the second time, and basically got everything as close to perfect as I could…. Put it back on the bike, and same crappy brakes. Mushy, weak, but sort of grabby at the same time under low braking force, awful!!

What is particularly troublesome about this is there’s no reason that I can see that these brakes shouldn’t be wonderful, its not rocket science, just basic physics, and there is nothing “wrong” here, although I would say there was an unacceptable amount of crap/crud inside the calipers, I don’t recommend taking them apart, it is just too much work for no gain. After all that work I feel I basically wasted a number of hours I could have spent riding!!

So I’m staring at it watching the rotor move in and out probably a 1/16” while I apply the brake, puzzled by this, because it didn’t make sense then I realized the rotor was actually moving the other way at the other end of the pad…. And even to my eye it looked as though the caliper was flexing but this can’t possibly be it – there is no way you are going to flex a casting as stout as that caliper!!!

Turns out that the powder coating on the forks, where the caliper mounts, was sort of chipped/peeling off, but unevenly, and causing the caliper to mount slightly “off” by a few degrees – a few minutes with a file to clean up the mounting surface fixed this up, and instantly improved matters by 100%. I have yet to ride anywhere other than the backyard with them, but am almost sure the problem is 100% fixed. I went from barely being able to lock the front wheel, and basically being able to pull the lever all the way to the bar, to being able to do nice controlled rolling stoppies, and having a nice firm lever. These brakes are every bit as good, now, as the AJP’s on my 2011. I think – I will know for sure on Tuesday!

So to summarize, if you are not happy with the Formula ABS brakes, I would recommend the following steps:

- disassemble and clean the master cylinder.
- lube the lever pivots
- adjust the levers inwards - they are quite a bit shorter than standard AJP levers, you can`t have room for more than two fingers on these.
- make sure the caliper is straight to the rotor and the rotor is not deflecting as the brakes are applied (and conversely springing the pads out when you let off the brakes) - this used up a lot of lever travel on miine and the misalignment was affecting performance too.
(edit - I have also heard from a more than reputable source that switching to dot 5 silicone fluid helps clear things up too - but that does require a complete clean/flush of the system)

I`d love to hear any feedback on this - good luck and keep your feet up!!!

Jon N.
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Old 05-14-2012, 01:47 PM   #2
lineaway
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Joined: Oct 2011
Location: nm
Oddometer: 2,283
Thanks for that! Not the first time that I`ve seen an easy fix that the factory should of caught. The `93`s came with the wrong length of shoulders on the caliper bolts causing an air leak every time you pulled the lever. Quite frustrating to have to figure things like this out on new bikes!!!
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Old 05-14-2012, 02:08 PM   #3
2whlrcr
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Joined: Jan 2005
Location: Dubuque, Iowa
Oddometer: 5,623
I have a 12 GG with Formula brakes. I had similar issues. Front brake seemed to have good feel and it would lock up the front, but not without extreme lever pressure and the authority I liked. I was coming off of a Beta with Grimeca sp?, that worked great out of the box.

I figured the brakes just needed bedding in and gave it about 5 hours with no change. Finally took the master cylinder cover off and it looked like muddy water for hyd fluid. I concluded it was also contaminated with aluminum dust, although I could not see any actual particles. I just flushed the system with new oil and the brakes work as they should now. I also shot some WD40 on the pivot point too smooth out the action. I didn't have to do anything with the caliper alignment.

I should also check the rears, but they work well so I have ignored them so far. I have about 10 hours on my bike so far.
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Old 05-14-2012, 03:10 PM   #4
Twin-shocker
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Joined: Jan 2012
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Sorry if its a stupid question, but if these brake problems are on new bikes, is there any reason owners need to mess around sorting them out?
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Old 05-14-2012, 03:44 PM   #5
2whlrcr
gooligan
 
Joined: Jan 2005
Location: Dubuque, Iowa
Oddometer: 5,623
Well, you would have hoped the manufacturer would have sorted them out, before they got into the hands of the public, but stuff like this happens occasionally. And when the closest dealer is 4 hours away, you can't go running back for every little thing that's wrong.
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Old 06-08-2012, 12:45 PM   #6
Jonny042 OP
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Joined: Mar 2012
Oddometer: 71
Another tip.....

Another pro-tip on the Formula stuff for those who are interested - the thumbwheel type adjuster on the levers is a little "loose" and will actually turn off the detent and drastically change the clutch and/or front brake biting point, with no warning. I am pretty sure I took a few points (and at least one crash) in CO from this, by the end of the day Sunday I developed the habit of checking both levers before entering a section.

So, here is the tip (stolen from whoever thought to do it on Pat Smage's bike) - wrap the adjuster threads with a few turns of teflon tape, just enough to provide a bit of resistance to turning so the slot on the adjuster stays lined up with the lever.
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