Got some new XT 785 brakes last week but the hoses are miles too long.
Did a trial fit and I think I managed to bolx the front piston in some fashion 🙄 :(. I've had a 183 rotor on the front with the Elixr's and whilst prating about with mounting adapters I think the pads were too high as the pistons seemed to close up too much and oil has appeared out the caliper.
Q 1
Would the pistons opening too much pliss oil out, and if so, is this just a case of just topping them back up?
Q 2
I understand you shorten the hoses at the lever end but again have seen different instructions on the matter. Can you also re use the little barb if you get it out cleanly? - I'm not sure I can get spare barbs and olives today and need to get this sorted tonight.
Q 3
I'm going to get a 160 rotor for the front and should have enough adapters, bolts etc. What else do I need spares wise? I see a cheap Shimano mineral oil kit and a bludy expensive one, both being separately referenced in different instructions? ❓
Happy to do just about every bike maint task going but have never done brakes and I don't really want to spend all night on't job. - Two LBS are full booked otherwise I'd just cough up to get it sorted .
Cheers
A1) yes, and oil-out will probably mean air-in (probably needing a bleed)
A2) i shorten at the lever, but it's the same thing really, good luck digging out the barbed pin without damaging it, i wouldn't recommend it, but it might work (good luck)
A3) spares? - pads.
bleed kit = 1x50ml syringe, 1x10ml syringe, 2x5" lengths of clear hose (windscreen washer hose works well)
the big syringe is for forcing the oil in from the bottom/calliper, the little syringe is for hoovering the oil from the lever/reservoir before it overflows.
if you're tight, you don't need shimano brake fluid, you can use LHM fluid (for some citroen brakes i think), but it's green instead of pink, and a little 'thicker' - you can just about notice that the lever action is a little slower on brakes filled with LHM fluid.
A2, Whilst you may get the barbed fitting out of the hose, the olive will be compressed onto the hose and is not re-usable.
That is why Shimano sell the pair together.
CRC usually have them available....next day delivery?
Cheers folks
I'm not that fussed about a few quid here or there so it'll be a trip to Evans for the bits though they don't appear to list the olive and barb.
ahwiles
I have an Avid bleed kit with syringes so can use them but I still can't get my head around what the [url= http://www.evanscycles.com/products/shimano/disc-brake-bleed-kit-ec012166?query=bleed%20kit ]expensive Shimano kit[/url] does that's different? ❓
hmm, i'd make sure the avid syringes are VERY clean before using them on your shimano brakes, i've got no idea what will happen if you contaminate shimano brakes with a little DOT fluid... (?)
the expensive shimano kit includes a clamp that holds onto the brake lever, and seals against the rim of the reservoir. there's a little tube through the lid so that you can easily collect the excess fluid as the reservoir fills.
personally, i just use a little syringe to hoover the oil out of the reservoir. (making sure i don't empty the reservoir)
With the 785 brakes you don't need a fancy clamping bleed kit. All you need is the small yellow pot that screws into the reservoir hole.
[url= http://techdocs.shimano.com/media/techdocs/content/cycle/SI/Deore-XT/SI_0116A/SI-0116A-001-00-Eng_v1_m56577569830746864.pdf ]BLEED INSTRUCTIONS[/url]
When I have bled these I have worked bottom up with a large syringe pushing fluid in and another syringe taking the excess out of the cup.
[i] i've got no idea what will happen if you contaminate shimano brakes with a little DOT fluid...[/i]
If the seals come into contact with DOT fluid they go kind of mushy then stop working. Any contamination with DOT will mean your nice new brakes are fit for the bin and nothing else.
ahwiles
The Avid kit hasn't been used so no worries about contamination.
Mr P
That's the destructions I've got. I got a 50ml tube of oil earlier but where do you get the pot etc etc? - These don't seem to feature in the expensive bleed kit?
How difficult is it to do a single all singing and dancing kit? 🙄
Ask your LBS to order an SMDISCBP from Madison for you. This is the little yellow pot you need. SRP is £3.99
There will be a complete bleed kit for these new types of reservoirs coming soon, but not soon enough if you want your brakes working this month.
Sorry , back again
My LBS (the HQ of a big firm beginning with E) have said 10 + days for that funnel! 😆 🙄 but I can source it elsewhere for Thursday though.
I'm going to try trimming the rear hose tonight but the front still has oil residue on the caliper so is it possible that the I did knack the pistons by over extending them? - A bit of conjecture on my part but I think I somehow didn't have the disc in fully and the pistons may have closed at an angle?
I'm fully aware that this [b]is[/b] world class stupidity on my part and I don't want to waste oil by refilling them only to watch it all come straight out the bottom because the piston isn't sealing or whatever.