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Discussion Starter · #1 ·
Been running k18's for about a year. In that year the front (with 180mm disc) has been spot on. Faultless.

The rear is another story. Re-bled about 7 times, twice done by "pro" shop mechanic. It seems to last a week or so, then I get a spongyness at the lever end, where it was a firm and positive bite. The brake still works, it stops the wheel, it just never seems to be as spot on as the front. Gone through the process time and time again, even using brand new o rings.

I can't even do a warranty on them, as they were off the 'bay and are OEM's that were brand new in bags but not covered by UK warranty IIRC.

It's bugging me. Why is the front so rock solid - it's the brake I use most, and the one that has the larger disc.

Any ideas before I try another re-bleed? Is it worth winding the lever throw all the way in (or out) before the bleed? Running out of ideas now!
 

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Thats funny i have the exact same problem with my front k24 brake, I have to pull it all the way the handle bars before she starts to bite it was never this bad so idk whats wrong with it cause I have not had any wrecks or anything. I have bled it 3 times now.
 

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dogonfr said:
Have you tried replacing the hose insert and compression fittings. :)
What would this random piece of advice help, especially if there's no external leakage. One bit of advice I do know you're not mentioning (which makes your post even more strange) because you were in those threads, is the possibility of needing a new MC piston as some were sent out of the factory made of an inappropriate material that doesn't function well with brake fluid. The only way to know is to speak to Formula. I personally know of one person that bought Formula, bled them over and over, had the same symptoms and then sent them back to Formula USA who changed the pistons, but didn't really say much about it. They seemed to focus more on speaking about bleeding (with changing around some parts).

I don't know if this will be your experience, but you're likely going to have to go to your Formula distro. For this year, these are not the brakes to buy without a warranty.
 

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Discussion Starter · #5 ·
Jerk_Chicken said:
What would this random piece of advice help, especially if there's no external leakage. One bit of advice I do know you're not mentioning (which makes your post even more strange) because you were in those threads, is the possibility of needing a new MC piston as some were sent out of the factory made of an inappropriate material that doesn't function well with brake fluid. The only way to know is to speak to Formula. I personally know of one person that bought Formula, bled them over and over, had the same symptoms and then sent them back to Formula USA who changed the pistons, but didn't really say much about it. They seemed to focus more on speaking about bleeding (with changing around some parts).

I don't know if this will be your experience, but you're likely going to have to go to your Formula distro. For this year, these are not the brakes to buy without a warranty.
These are not the batch that had the problems with the MC pistons - totally different serial numbers.

Can't send them to Propel (the UK distros for Formula) becuase although I bought them brand new off a reputable eBay seller, they are OEM and IIRC not covered by a UK warranty. (Which serves me right I guess for buying them cheap off eBay! Had I known they weren't covered I might not have bought them). However.... When the back works, they are probably the nicest feeling brakes I've ever used - the bite and stopping power is incomparable to anything at the same price point and above, and the modulation is superb.
 

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You can send it to them. You need to speak to them about a procedure and will likely have to pay. Having to pay for a repair is not the same thing as "I can't send it back".

Dude, these are your brakes, your life is potentially in danger with unreliable brakes. Fix them, get them fixed, or replace them.
 

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aphex2k said:
These are not the batch that had the problems with the MC pistons - totally different serial numbers.

Can't send them to Propel (the UK distros for Formula) becuase although I bought them brand new off a reputable eBay seller, they are OEM and IIRC not covered by a UK warranty. (Which serves me right I guess for buying them cheap off eBay! Had I known they weren't covered I might not have bought them). However.... When the back works, they are probably the nicest feeling brakes I've ever used - the bite and stopping power is incomparable to anything at the same price point and above, and the modulation is superb.
Check with these guys and see if they can offer any assistance or advise :thumbsup: , http://bythehive.com/
 

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Jerk_Chicken said:
What would this random piece of advice help, especially if there's no external leakage. One bit of advice I do know you're not mentioning (which makes your post even more strange) because you were in those threads, is the possibility of needing a new MC piston as some were sent out of the factory made of an inappropriate material that doesn't function well with brake fluid. The only way to know is to speak to Formula. I personally know of one person that bought Formula, bled them over and over, had the same symptoms and then sent them back to Formula USA who changed the pistons, but didn't really say much about it. They seemed to focus more on speaking about bleeding (with changing around some parts).

I don't know if this will be your experience, but you're likely going to have to go to your Formula distro. For this year, these are not the brakes to buy without a warranty.
Jerky they can draw air without leaking out. :eekster:
 

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stealthbombers
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Make sure the shop mechanic pulls the air out of the caliper with the syringe, prior to pushing the oil towards the lever. I forgot this step and after a few bumps the brakelever touched the grips.
 

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knef said:
Make sure the shop mechanic pulls the air out of the caliper with the syringe, prior to pushing the oil towards the lever. I forgot this step and after a few bumps the brakelever touched the grips.
how do you do that cause I never have b4 I dont think? that might be my problem cause i can pull them almost all the way to the handle bars.
 

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stealthbombers
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clvlc4door said:
how do you do that cause I never have b4 I dont think? that might be my problem cause i can pull them almost all the way to the handle bars.
Get the bleeding instructions pdf here: http://www.formula-brake.it/en/support/downloads/k18
It's step 9 that is really important. But unlike I said earlier, apparently, this step is past the step involved pushing the oil towards the lever. It's a pretty clear manual.
 
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