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Discussion Starter · #1 ·
I have a weird and annoying problem on my front Oro Puro.
It seems that the master cylinder is not able to compensate for pad wear- to explain with an example:
I put new pads in, and after bedding'em and centering the calipers, I race a 50Km marathon event. The brake feels perfect at the start, but by mid race the lever throw is increasing (not related to overheating), and by the end of the race, the lever almost touches the grip – even when the brakes are completey cold.

At home, I pump the levers a few times, and the situation doesn’t change. So I remove the wheel, pump the lever a few times, and see that (obviously) the pads come closer to each other.

Now I space the calipers apart with a screwdriver, mount the wheel an recenter the caliper. After pumping the lever a few times, now the pads contact the rotor with a very positive feel and the lever throw is perfect: not too tight, not too "slack". So far so good, but during the next long ride the lever throw problem is occurring again. By the end of the ride, the lever is almost touching the grip.

At first I was thinking that the reason of this weird behaviour was a system underfill, so repeatedly bled the brake, with no result. The lever feel is very solid, so probably no bubbles in the fluid. I also tried to bleed the damn brake using an old set of worn-out pads, just to have some extra fluid in the system. No results.

The rear brake has a very consistent feel, and the lever throw remains the same throghout the entire pad life – as it shouldbe on any good disk brake system! The same pads -formula organic- are used front and rear.

Hope the problem description is clear.
Formula experts, any advice to trobleshoot this? Thanks in advance

PS
for simplicity, lets assume the FCS lever position wasn’t moved in the process, so let’s keep the FCS out of the picture
 

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Discussion Starter · #3 ·
Didnt think about that, I'll check if one of the piston is sticky, lubricating the seal/piston interface with a drop of brake fluid- It will take less than 5min.
Even though I don't see any direct connection between a sticky piston and the problem I described , it will be worth trying.
thanks
fab
 

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This very same thing happened to me with my Ones. Any word on the cause solution?
 

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Same here with The Ones. The bleeding instructions are also incorrect to get adequate power - follow them and you get 70% of the throw of the lever as useless dead space as you end up with insufficient oil in them.. well i was and was folllowing to the letter :(. Got it better by a bodge.. still not happy as i've still got to set the FCS and reach to maximum.

Basically these brakes are dangerous IMO as you can't trust them to function consistently over a ride as mentioned above. Had a nasty off the other day as at the start of the ride they were ok but later on even with the lever to the bar it couldn't grip the disc hence i couldn't slow down enough - result bottom of an embankment with the bike ontop of me :(.

I've bled them mysef - had them in the shop multiple times for bleeds and the shop guy is telling me he's seeing loads with the same issue!

Had them done again today - rode 7 miles or so and the lever was creeping towards the bars even in this space of time. Mine have also started sticking and/or are sluggish on return.... Are Formula gonna recall these before someone hurt - surely these are faulty?

Apparently if you speak to Formula they tell you your the first person with this problem and they've not heard of it!.
 

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Rocketmagnet:

That's very disconcerting. I bought these brakes not only because of all the positive reviews on their performance, but largely due to reports of Formula's excellent customer service.

Also, you mention Formula's bleeding instructions being inadequate.. can you elaborate on what should be done differently?
 

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Aye same thing here - I just think the reviewers didn't ride them long enough.
My pads have loads of meat on them but the pads hold so far away from the disc to begin with most of the lever travel is taken up closing this distance.

As for Bleeding I fiddled a bit with various things.. mainly the lever position at various stages. However i'm not going to advise directly as it goes against Formulas instructions hence if damage occurs or injury to the rider.. well I'm not going to make myself liable.

I suppose I could use the FCS to adjust for pad wear (which isn't really what it should be used for) but currently I'm setting it to max just to get them to bite so the FCS aswell as the reach adjust is absolutely pointless.

Just remembered in addition to my other problems my rear brake FCS seems to be siezing up also - but this is so minor to the brakes failing and the potential for serious injury it hardly matters.

My front is significantly worse than the rear and it's ultimately what caused my crash - luckily neither bike nor myself got badly hurt - just winded/dazed and a bit muddy.

I'm riding them and the brakes are totally ruining my riding - I just can't trust them to work consistently and now has me creeping into stuff i should be nailing. It's absolutely irrelevent how well a brake works if it can't do it 100% of the time.
 

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Discussion Starter · #10 ·
I solved my problem in two ways.
First I lubricated the lever bushings and pistons seals with dry chain lube and DOTfluid respectively.
This step slightly improved the lever feel, and almost eliminated the sticky lever syndrome
The biggest problem (lever going to the bar) was troubleshooted by chance. I noticed that the reach adjusting screw of the rear brake was unscrewing a tiny bit at each lever pump. After a short ride, the lever had crippled toward the bar (short reach) thus giving the impression that the system was not working properly. Simple solution to a seemingly complicated problem: thread locker on the reach adjusting screw.
In any case the rear lever is still "stickyer" than the front, and I will order a spare master cylinder from Chain Reaction as soon as it's availabe.
fab
 

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Unfortunately it's not the reach adjust screw on mine. My LBS lubed up the other day as you said and it made no difference to the feel. The pistons are sluggish to return - they should spring back instantly - heck I found myself unconciously pushing the rear brake lever back out manually.

The main point like i've been making already - your reach adjust was bringing in the lever towards the bar but this should still bite at the same position relative to the bar for a certain extent - the bite point is what the FCS is for but i've also got to set this to max or they wont bite at all until some virtual point beyond my bars:(.
When you twist the knob it just moves the lever closer and not the piston - Formula have this as a Feature however - but if you can't get it to bite for 30-50% of the throw you need to have it wound all the way out thereby rendering the reach adjust as useless.

I'm not sure but I think this whole problem stems from the fact that the resevoir is too small and it's a fundamental design flaw?.

My brakes are new and should function out of the box - i've hardly ridden them as my bikes been in the shop trying to sort out the things. I do everything myself normally but these are a total nightmare.

I'm really frustrated with these brakes, Formula are no help and I really need to send these back so they can replace them and inspect mine to see whats wrong with them. I've contacted the EU Formula people and got a gibberish reply in pigeon english, then nothing from subsequent emails :(.
 

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RocketMagnet said:
Same here with The Ones. The bleeding instructions are also incorrect to get adequate power - follow them and you get 70% of the throw of the lever as useless dead space as you end up with insufficient oil in them.. well i was and was folllowing to the letter :(. Got it better by a bodge.. still not happy as i've still got to set the FCS and reach to maximum.

Basically these brakes are dangerous IMO as you can't trust them to function consistently over a ride as mentioned above. Had a nasty off the other day as at the start of the ride they were ok but later on even with the lever to the bar it couldn't grip the disc hence i couldn't slow down enough - result bottom of an embankment with the bike ontop of me :(.
I am going to absolutely disagree with you here. I have performed the Formula brake bleed procedure on my MEGAs and they are rock solid. I followed the procedure EXACTLY. If you follow the proceure you will have more than adequate fluid in the system.

As far as your comment that the brakes are dangerous, I think you are mistaken. And I am being polite. There are a large number of riders using ONES out there with NO issues whatsoever. This being the case, it would appear that you either performed the bleed incorrectly, or have parts that are in need of warranty service. More than likely it is the latter.

I also have a hard time believing you have a local shop that has seen "loads" with the same issue.

RocketMagnet said:
I'm not sure but I think this whole problem stems from the fact that the resevoir is too small and it's a fundamental design flaw?.
Seems to be plenty large for 99.99% of the riders out there.
 

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(I don't have the Formulas and am relating them to the Hayes, which I have.) Instead of pushing the pistons all with way in before you performed the bleed, you leave them partially out. That way you can slightly overfill the system.
 

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MikeDee said:
(I don't have the Formulas and am relating them to the Hayes, which I have.) Instead of pushing the pistons all with way in before you performed the bleed, you leave them partially out. That way you can slightly overfill the system.
This is what I was thinking also with a little extra, if the pads are grabbing or dragging the rotor you can put feeler gauges between the pads and rotor, I use .015 with Hayes, install a short length of hose to the caliper bleed nipple and loosen it this will allow the pads to adjust where you want them then snug closed. Remove the feeler gauges and check operation, if to sensitive then go up on feeler gauge size till adjusted where you want it. :thumbsup:
 

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Formula USA replied on this forum that if the lever feel has too much travel, you can remove the wheel and pull the lever *once* and replace the wheel. This will give a decrease in free travel that will be lost when the pads wear.

The issue being surfaced on this thread is not something I have encountered with my set of the Ones or the other set I fitted to a friend's bike.

This is what I do know. The Ones are very sensitive to good setup. That means facing the mountings on the frame and setting up the caliper clearance with feeler gauges. Because of the hydraulic ratio of the brakes, any opportunity for the pads to be knocked back results in a long lever feel. Set up correctly they do not do this.

Forcing extra fluid into them on a bleed without addressing brake spot facing and caliper alignment is a bodge. It isn't necessary. It isn't how the brake is designed. It isn't a suggestion that I'd take seriously. There is nothing wrong with Formula's bleed procedure when the brake is a) not faulty and b) installed correctly.

For RocketMagnet:

You're UK based. I don't know where you got the brakes. The shop you bought them from should handle warranty issues with the distributor (Propel) - no need to make it complicated by attempting to contact Formula directly. Propel are pretty responsive. You are correct that the lever position adjust means that the bite point moves in towards the bar. It just sounds like you have far too much free travel which is a setup issue. Mine started off with a bit too much pull on the lever but spot facing has made them perfect. I just use FCS to make the lever feel equal between front and rear. That means that the FCS is set to give the furthest bite on one of the levers and the other one is adjusted to match.
 

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Formula has a tendency of PM'ing people then dealing with them off forum so regulars dont know what the real deal is. When the consumer replies back it is a simple got a PM and they work. Personally I call that poor CS but there are allot of people seem to like it that way. :cool:
 

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I solve that problem trading the OEM Mater Cylinder Piston with a new one. The difference is that the one that came with the brake are all plastic and the one that I buy are in aluminum and plastic. And the plastic part is much stronger too.
No more problem ....
 

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TLL i'm just very frustrated with these brakes, they arrived with bits missing from the box (the shortening bits) and have been a pain to set up.

I've seen some latter comments and will pass them onto my LBS, however they deal with Formula brakes all the time as their dealer models have them fitted as standard. They have also been speaking directly with the Formula Tech guys trying to resolve the issues they have had with some The One's.

The LBS confirmed they were setup properly but reset them anyway - seems like mine could indeed be faulty. The LBS has been speaking directly to the Formula Tech guys about the issues he's seeing - so far they have not been able to resolve this issue.

As for the comment about a number of people with issues - i'm speaking to a dealership that has Formula brakes as standard and they are telling me they have had numerous issues with The Ones. In fact they told me they had two identical bikes in with The Ones on - one of them was fine.. the other was experiencing similar problems to mine.
So i'm not sure where your getting the info that nobody has problems with them.. if that was the case there wouldn't be any posts here or elsewhere.. yes it could be setup issues in many cases but a fiddly setup is intself an "issue".

As for the bleed proceedure both myself and the shop extended the piston out slightly to increase the oil.. makes sense - but it's still not adjusting itself for pad wear. IMO this is dangerous. I would guess mine are faulty out of the box and i'll need to get them looked at - sluggish non returning lever pistons on a brand new set isn't good QC.

I wasn't stating fact that the resevoir was too small - the clue is the question mark at the end ;)

TLL.. are you having to adjust your FCS during pad wear or are they just self adjusting ok themselves. What do you do when you replace the pads.. are you pushing the pistons all the way back in?
I do agree it sounds like not enough oil in but im dealing with an LBS thats got Formula as stock so they should be able to bleed em right?
Something which i'm not sure about is do you set the FCS to it minimum during the bleed.. the instructions don't say so maybe it doesn't impact?
Also can you wind your lever all the way in and still get them to bite before they contact the bar?

Cheers
 

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My K24s were terrible for this. I sent them back to propel (very nice chap, Toby, but 4 week turnaround is a bit long) who swapped the master cylinder (lever) pistons for the new metal ones. Apparently the plastic OEM ones on the older models decayed over time due to exposure to the DOT fluid.

BUT - mine are still cr*p at self-adjusting. I have to pump the lever seven times to reset the pads before a long ride, then afterwards they're back to where they were; with the lever travel way too long. This is a big problem for people with short fingers (like me) because, with lever reach adjusted, the bite point is about 1cm from the bars.

I'll try lubing the pistons with brake fluid but I can't see it lasting long. Failing that some silicone brake grease might be worth a pop.

I can't see how bleding with the pistons slightly out will make a difference; with a few stops the lever reservoir will just store the extra fluid and you're back to square one. It's the actual design that's at fault - the K24s have fantastic modulation because they have a lot of lever movement to move the pads a small distance.
 

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Oh forgot to say - I've now started to pump the brakes before a major 'stop'. It's now second nature to pump the levers a few times in the run up to the braking zone to move the pads a bit closer to the rotor. Which is great until I need to stop unexpectedly!
 
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