Martin PJ Posted June 20, 2016 Posted June 20, 2016 Exactly that. Pressuring the system by pumping the lever shows there's definitely air in the system. Problem is how quickly it is going from being perfect to needing a fix. The new shop I took it to says it needs to be 'bled under pressure'. Not quite sure what that means relative to the normal way the other shop did it, but we'll see. Like I said above, the old XT on my 26 didn't need it at all. Not sure I understand what the shop means. With the Formula one you can bleed it, after bleeding the brake still goes almost all the way down. Pump the brake lever with the wheel out, the brake will come right up when you put the wheel back. It will stay like that for a month or two, until the brake pads start to wear. Then you need to do it again. It is not air in the system. If you want the Formula ones tight after a bleed, then you need to bleed with old brake pads, then put the new ones in after bleeding. Maybe let out a few drops of brake fluid to get the new pads in. I have heard reports that other brake pads can be like this, as I said, the problem is the brakes are not really self adjusting.
Lefty V Posted June 20, 2016 Posted June 20, 2016 Ok, we might be onto something. Bike is almost a year old. Have done 1500 km of which most of it was in the last 3 months. I have not done any maintenance on the brakes yet.Is this the point where I can mention how many 1000s of km I go between bleeds on my Elixirs?...or should I wait 4 days?
Jewbacca Posted June 20, 2016 Posted June 20, 2016 Use your brakes like ABS brakes. Short bursts tuktuktuktuk.. Pulling on them consistently engaging the rotor will boil the brake fluid. I ride a lot of dodgy stuff, long descents, super steep hiking trails and other silly adventures with SLX brakes and haven't had any issues. Guys also use their back brakes a LOT trying to regulate speed where the front brake will do it faster...... Most people cook their back brakes and their front remains good to go. Getting to grips with the right technique is as important as equipment. Also, you might want to check the olives and banjo seals now that you have cooked the brakes.... The shimano hose can get brittle after all the heating/cooling and cause air and contamination quicker. Good luck.
Thor Buttox Posted June 20, 2016 Posted June 20, 2016 This is not always the case with Formula. They tend to have a large amount of lever travel for the related piston travel. Thus as the pad ware down the lever has more and more free stroke. It is not that there is air in the system or the brakes are not bled properly. I normally over fill the reservoir to solve this but then your brakes can pump up if they left in the sun.Thanks Spoke - forgive my cluelessness but what is 'Formula' and is it related to XT? I quite literally have my bike being bled today and would like to ask them for future reference?
JXV Posted June 20, 2016 Posted June 20, 2016 Thanks Spoke - forgive my cluelessness but what is 'Formula' and is it related to XT? I quite literally have my bike being bled today and would like to ask them for future reference?'Formula' is a brand of MTB brake. Not related to Shimano.... Sent from my SM-G900F using Tapatalk
Thor Buttox Posted June 20, 2016 Posted June 20, 2016 Not sure I understand what the shop means. With the Formula one you can bleed it, after bleeding the brake still goes almost all the way down. Pump the brake lever with the wheel out, the brake will come right up when you put the wheel back. It will stay like that for a month or two, until the brake pads start to wear. Then you need to do it again. It is not air in the system. If you want the Formula ones tight after a bleed, then you need to bleed with old brake pads, then put the new ones in after bleeding. Maybe let out a few drops of brake fluid to get the new pads in. I have heard reports that other brake pads can be like this, as I said, the problem is the brakes are not really self adjusting.Thanks, Martin. Not sure if I have the knowledge to explain this but am going to find out about the self-adjusting. But: in summary, Are you saying that if I pull my lever repeatedly and fast and it retreats further from my bar to catch, that this is NOT due to air in the system, or may not be? Edit: as two different LBSs have said it is due to air, and I've now bled them three times in two months, I would appreciate the advice if there is something odd with the XT's I need to look at. (Sorry, totally misunderstood about Formula)
Spoke101 Posted June 20, 2016 Posted June 20, 2016 Thanks Spoke - forgive my cluelessness but what is 'Formula' and is it related to XT? I quite literally have my bike being bled today and would like to ask them for future reference?http://www.rideformula.comItalian brake and fork manufacture. There top end brakes a known for being some of the lightest, most expensive and very fiddly pain in the ar$e.
Bateleur1 Posted June 20, 2016 Author Posted June 20, 2016 http://www.rideformula.comItalian brake and fork manufacture. There top end brakes a known for being some of the lightest, most expensive and very fiddly pain in the ar$e. Italian = some of the lightest, most expensive and very fiddly pain in the ar$e
Martin PJ Posted June 20, 2016 Posted June 20, 2016 Thanks, Martin. Not sure if I have the knowledge to explain this but am going to find out about the self-adjusting. But: in summary, Are you saying that if I pull my lever repeatedly and fast and it retreats further from my bar to catch, that this is NOT due to air in the system, or may not be? Edit: as two different LBSs have said it is due to air, and I've now bled them three times in two months, I would appreciate the advice if there is something odd with the XT's I need to look at. (Sorry, totally misunderstood about Formula) No, if you pump it and it comes up with the wheel in place, then that is air. With the Formula One brakes, the deterioration is because of brake pad wear. With most brakes as the pads wear with each pump of the brake more fluid will go into the line and maintain the feel of the brake, so the brakes self adjust as brake pads wear out. With the Formula One brakes this doesn't happen unless you take the wheel out and give the brake lever a few big pumps, this pushes more fluid into the brake line. I am not an expert on XT brakes, I would try another bike shop. Maybe they are bleeding the wrong. From what I see, bleeding brakes is not rocket surgery. If you do it every day, then you should have it taped.
Martin PJ Posted June 20, 2016 Posted June 20, 2016 http://www.rideformula.comItalian brake and fork manufacture. There top end brakes a known for being some of the lightest, most expensive and very fiddly pain in the ar$e. The Formula One are OK, but if you can get XT, then take them. I think XT are miles better.
Thor Buttox Posted June 20, 2016 Posted June 20, 2016 No, if you pump it and it comes up with the wheel in place, then that is air. With the Formula One brakes, the deterioration is because of brake pad wear. With most brakes as the pads wear with each pump of the brake more fluid will go into the line and maintain the feel of the brake, so the brakes self adjust as brake pads wear out. With the Formula One brakes this doesn't happen unless you take the wheel out and give the brake lever a few big pumps, this pushes more fluid into the brake line. I am not an expert on XT brakes, I would try another bike shop. Maybe they are bleeding the wrong. From what I see, bleeding brakes is not rocket surgery. If you do it every day, then you should have it taped.In theory. Before I put the XT on my 26 the bike came with Elixir's. They had a design flaw where it was impossible to seal the reservoir at any angle without a little fluid dripping out and causing a bubble. Basically as a result the reservoir shape and where the screw was. Just hoping the new XT's aren't similar. Can't find anything though - just hope it can be fixed.
Spoke101 Posted June 20, 2016 Posted June 20, 2016 The Formula One are OK, but if you can get XT, then take them. I think XT are miles better.XT's are way to heavy R1 Racing all the way
Thor Buttox Posted June 20, 2016 Posted June 20, 2016 So I have been informed I have a leaking master cylinder. And now I will be without a bike for a while as it goes for a warranty claim. Eish... Not sure which is worse, the brake giving grief or not having a bike.
HappyMartin Posted June 20, 2016 Posted June 20, 2016 So I have been informed I have a leaking master cylinder. And now I will be without a bike for a while as it goes for a warranty claim. Eish... Not sure which is worse, the brake giving grief or not having a bike. Not having brakes on steep decents is definately the worst.
Thor Buttox Posted June 20, 2016 Posted June 20, 2016 Not having brakes on steep decents is definately the worst.True. But thinking 'As long as the front one is one the bike i'll be ok' is also fair thinking. Especially if I need my *wrong thread* Disco points!
Bateleur1 Posted June 20, 2016 Author Posted June 20, 2016 Not having brakes on steep decents is definately the worst.Due to recent experiences I can agree
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