paul 22 Posted January 3, 2014 Report Share Posted January 3, 2014 Just bought a 2012 sherco 300 cabastany an it has formula master cylinders! Hav a real problem gettin the brake to hold my weight it just slips through! Flushed out the fluid witch was really dirty an replaced it with fresh stuff still no better! Could anyone suggest anything that would help me get a decent brake!?? Thanks Quote Link to comment Share on other sites More sharing options...
chris west Posted January 3, 2014 Report Share Posted January 3, 2014 Have you checked the condition of pads .. If good maybe clean down both sides with some light sand paper and try again Quote Link to comment Share on other sites More sharing options...
paul 22 Posted January 3, 2014 Author Report Share Posted January 3, 2014 (edited) Took pads out an heat them an cleaned them still no difference!! Few ones I spoke to changed the master cylinder an hose but surely that's a bit extreme or maby there rite and formula is a poor brake???? Edited January 3, 2014 by paul 22 Quote Link to comment Share on other sites More sharing options...
steve_earle Posted January 3, 2014 Report Share Posted January 3, 2014 Firstly, what does the lever feel like, Is it spongy or is it solid? If you lever is solid and positive and adjusted properly then I'll bet the pads are your problem. You can do the old trick of riding the bike with the break on and getting them hot then pouring water on them but the best way is to chuck the pads away and stick a set of Galfer pads in. I have never had to bed in a set of Galfer pads just stick em in and instant front brake. If you already have the red backed Galfer pads then you have a problem, We will need more info to sort it out over the internet. There is hundred of threads on breaks and all the answers are there just do a search. Quote Link to comment Share on other sites More sharing options...
paul 22 Posted January 3, 2014 Author Report Share Posted January 3, 2014 It's really spongey! Can pull it to the grip! There's no adjustment on the lever to set the plunger only an adjuster for reach! Had a 2010 gasser before this an brakes were amazing! Quote Link to comment Share on other sites More sharing options...
steve_earle Posted January 3, 2014 Report Share Posted January 3, 2014 Hi mate, Pads may not be to blame just yet then. I would do a complete strip and thoroughly clean the master cylinder and the caliper. It could be crap or corrosion under the caliper seals or a knackered master cylinder seal. Has the brake always been spongy or only after the fluid change? I think the formulas had an update on the push rod pivots, Give Splat Shop a call. Quote Link to comment Share on other sites More sharing options...
copemech Posted January 4, 2014 Report Share Posted January 4, 2014 Get a pint bottle water and try the water trick first. I usually run up to 5th gear and do 3-4 god stop attempts to heat the rotor, then douse it ti steam off, repeat a few times then let cool to normal. If the lever feels firm initially, yet there is still some compressibility, this is not an indication of a problem. All brakes have some. Quote Link to comment Share on other sites More sharing options...
lineaway Posted January 4, 2014 Report Share Posted January 4, 2014 This is what you need. http://www.trialscen...-2013-upgrades/ Quote Link to comment Share on other sites More sharing options...
anotherfive Posted January 4, 2014 Report Share Posted January 4, 2014 I have formulas on my gasser and they were variable at the beginning but great now. One problem I had was that one of the ceramic pistons was chipped ( they are v brittle) from previous owner squeezing it back in. The two pots on the other side were in the wrong way round with the cavity facing the oil. I stripped them without undoing the access caps. It can be done gently and using old pads to protect the faces of the pistons. Air is also a bugger so this need to be got rid of. Watch v closely in the master cyl for pinpricks of air when beeding, and ensure the hose is always on the rise and not higher than m cyl at any point. Quote Link to comment Share on other sites More sharing options...
jojjas Posted April 13, 2014 Report Share Posted April 13, 2014 (edited) Not sure if I should start a new topic or just hijack this one but I'm having what seems to be exactly the same issue on my 2012 Sherco 2.9 so I start here. I have read both treads by jonny042 (#1, #2) about the Formula brakes but I just can't get what's wrong with my front brake. Just as paul 22 describes the brake is spongy and won't hold my weight, it's worlds apart from my friends -08 gasgas. I feel the pads engages when lever is about half way in but then I can continue to pull it to the the grip. I have disassembled the master cylinder and caliper and cleaned with isopropyl alcohol and also flushed the hose (old oil was grey, almost black!). Putting everything back again I have the same poor brake. I pulled the lever 75% in and locked it with a zip tie over night. Preassure didn't drop, meaning there is no leakage. I'm using galfer pads and have also sandpapered the pads to get good grip. I've cleaned the rotor with isopropyl alcohol. Still no improvement. This video shows what I see when pumping the brake (between "engaged" and almost in to the bar): I find this very interesting. It seems the force that is applied is enough to deflect the caliper but not enough to lock the brake. If I push back the pistons I can see that the two outer pistons (banjo connection side) engages first, then the inner front piston and the last one to engage is the one closest to the bleed valve. Could there still be muck in my caliper causing a pressure drop at the fourth piston? I'm really tired of this now Edited April 13, 2014 by jojjas Quote Link to comment Share on other sites More sharing options...
copemech Posted April 14, 2014 Report Share Posted April 14, 2014 So did you use the WATER as I suggested above? Quote Link to comment Share on other sites More sharing options...
tony27 Posted April 14, 2014 Report Share Posted April 14, 2014 Looking at the video it looks like some serious caliper flex going on, are the bolts holding the 2 halves of the caliper together tightened up fully Quote Link to comment Share on other sites More sharing options...
jojjas Posted April 14, 2014 Report Share Posted April 14, 2014 The Formula caliper is a mono-bloc construction, so there are no bolts to tighten. My only conclusion is that the force applied to the pads is more then enough (based on the fact that the caliper is flexing). This would mean there is not enough friction between pads and disc due to contamination or bad caliper alignment. I will give the water cooling method a shot tonight and see what happens. copemech, should I pour water on the rotor AND caliper or just the rotor? Quote Link to comment Share on other sites More sharing options...
copemech Posted April 14, 2014 Report Share Posted April 14, 2014 (edited) Pour the water over everything! Edited April 14, 2014 by copemech Quote Link to comment Share on other sites More sharing options...
jojjas Posted April 14, 2014 Report Share Posted April 14, 2014 Tonights update: The water method definitely helped a lot but still not as good as it should be. Got some advice from splatshop today on how to bleed the caliper properly, so after re-fitting new piston seals and bleeding I hope that the pistons will move evenly and add that last bit of force needed. I'll keep you updated! Quote Link to comment Share on other sites More sharing options...
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