update: been p*ssing about with them and ive made them better. but.....i dont think itll last :-/
why? well, i bled them as per the instructions, in fact i thought id messed it all up, because i was pulling on the syringe at the caliper, thinking i was pulling out any bubbles from that end, when i realised id taken all the fluid from the reservoir! so air had got in now!! grrrr.....
so i pushed it back hoping for the best, but resigning myself to the possibility id f*cked em up. obviously loads of little bubbles in the fluid, but once theyd calmed down i tried again. and as per instructions, the last thing i did was tube into waste bag, and opened bleed nipple and let it start draining into it, keeping reservoir topped up. ( i dont really understand that bit and why you should do it)
was expecting it to be real crap as id probably made it worse with the empty reservoir bit, but it was about the same, if not a bit better.
i did something that made more of a difference, but like i say, i dont think itll last. when id been putting that yellow spacer in between the pistons, it was loose, so kept dropping oout. which suggested to me that there was too much space between pads and rotor. and therefore too much lever travel before 'bite'.
so i took spacer out, and pumped the lever a few times to get the pistons out a bit further, so i had to force the spacer in. set it all up again, and obviously more of an instant bite. which is what i like.
am i right in thinking tho, that as the pads wear, the gap will just get bigger again tho, without compensating? and where does that free stroke screw come into this? i sort of thought that was what altered the lever travel.
sadex - you've probably read the posts froma few weeks ago when I was having similar probs with the same brakes from Ribble. Mine are now perfect 😛 I spent a good while bleeding them carefully - forcing fluid up from caliper with syringe, while reservoir horizontal, cap and rubber off and a makeshift dish tied to the bars to catch the fluid (It's new so reuseable as long as the dish is clean)I put through a load of fluid this way. I then did it reservoir down as per the Shimano instructions, which is the same as Hope (have a look on the Hope website which is very good). This sorted the spongy feeling. I then wound out the freestroke screw 2 full turns (as advised by bigyinn et al)and tweaked the nurled reach nut to get the initial bar/lever distance right. I am also running them inside my shifters, with the distances set up for 1 or 2 finger braking which also avoid lever/finger contact.
definately more of a footer than the older xt's I replaced, but much more powerful and better in just about every way. the only downside is that it is taking me a wee while to get used to not having indicator windows on rear shifter.
yellow spacer - was loose, so kept dropping oout. which suggested to me that there was too much space between pads and rotor. and therefore too much lever travel before 'bite'.
sorry, wrong (sorry).
the pistons pump out you know...?
if you pull the lever a little bit, the pistons move out a little bit, and then return to where they were when you let go.
if you pull the lever a LONG way, the pistons move out a lot more, but don't go back quite as far when you release the lever.
they automatically adjust for pad wear.
[i]when i realised id taken all the fluid from the reservoir! so air had got in now!! grrrr.....[/i]
🙄
ahwiles - you are correct, however if you bleed the system with the pistons a little further out (e.g a slightly thinner spacer) and then top up the reservoir, surely there is more fluid in the system and a quicker bite ?
no. it doesn't work like that.
(yes, you'll have a little bit more fluid in the system, but this will be represented by a higher level in the reservoir - which won't affect braking performance)
ok, I wasn't too sure about my theory anyway 😛
so theres practically nothing i can do to position the pads closer to the rotor and get a more immediate bite?
but i just DID do. it worked. or like i thought, will it just get worse as the pads wear, then back to original gap?
i wish i understood these open systems a bit more :-/
sadex - if you unscrew the freestroke screws 2 full turns this makes bite more 'instant'. It will also bring your levers in a bit, so wind them back to where you want as a starting point with the nurled nuts. Mine are now quite 'bitey' and feels better than my Hope mono mini's on the other bike, which in turn felt better than my older xt's. Shifting the whole unit in a few inches towards the stem made a big difference in the overall feel too, despite my initial scepticism !
[url] http://www.singletrackworld.com/forum/topic/who-rides-with-their-brakes-inboard-of-shifters-shimano-xt-content [/url]
iain, i use them on my singlespeed, so no shifters to consider 🙂
as far as the free stroke screw goes, i read in one of the many threads ive seen, that you had to have it screwed out to bleed them. is this right? whether it is or not, thats where they are now, so ive got no more to play with.
ta
I undid them about halfway as i wasn't sure if it would make a difference to the bleeding process. seemed to work !as far as the free stroke screw goes, i read in one of the many threads ive seen, that you had to have it screwed out to bleed them. is this right?
