Bleeding SLX!

tnwoolley

Had these brakes for 3 months now and love em.

Rear brake started to feel a bit spongy and eventually stopped gripping the rotor so I got some Shimano mineral oil, baggie and tube and followed the instructions (combined with tips from the workshop articles).

No joy. Went through the entire bottle of oil and witnessed many an air bubble coming out but once they'd stopped and I tied everything up, topped up the reservoir blah blah it was even spongier than before!

Back to the LBS for me tomorrow.

Anyone else despair at bleeding Shimano brakes? My Juicy 5s were a joy to bleed!

toasty

I've bled 4-5 of these beasties so far (if you include XT too! ). Without looking at the article here's what I do:

1: Stand the bike up straight, preferably in a work stand. Adjust the brake lever so the reservoir is level.
2: Remove the wheel and brake pads, put the little yellow block of cheese you got with your brakes in there.
3: Remove the top cap off the brake reservoir and ensure it's topped up, attach a tube to the little outlet bit at the bottom on the brake, lead the little tube into a bag or something. I put mine into an old water bottle.

4: Loosen the bolt at the bottom, then squeeze the brake lever in fully and keep them held down. Oil (and the odd bubble) will come out of the tube at the bottom.
5: Tighten the bolt at the bottom, now release the lever. This will suck oil in from the top, ensure the reservoir stays filled up at this stage.
6: Go to 4 about 20 times over.

7: Finally make sure everything is filled up and put the top cap on. I wash it all down with Fairy liquid, it noms off the mineral oil really easily.

One thing I'd note, air bubbles float upwards obviously. If the tube arcs downwards into a bag, you might get some stuck in the tube trying to go the wrong direction. Hold the tube upwards to coax them out!

tnwoolley

Cheers Toast,

Still...think I'd rather bung the mechanic £10 and not deal with the hassle. It cost me about £10 just for the worlds smallest bottle of oil and a crappy tube!

toasty

hehe true, I bled a mates set when I was up his end of the country last. Infact my crappy little bottle and tube has bled all of the brakes I've done so far, although I do reuse it if it's from unused brakes (hence using a water bottle to catch it).

They seem to be really badly set up out of the factory, absolutely tons of bubbles were coming out of his with every squeeze. Mine weren't much better when brand new either to be honest.

It's a handy thing to know though, my SLX definitely get air in the system much worse than my XT ones. If you have to take the wheels off your bike for transport ever be really careful of squeezing the levers.

dunker

can't you back bleed them like older lx/xt ones?

monster-mash

Sounds to me like you are drawing in air from somwhere, have you checked the security of the brake line bolt ?

pdid

I back bled my XT's:

1. Level up reservoir and remove cap.
2. Remove dirty mineral oil from reservoir with medicine syringe.
3. Attatch a length of tubing to a medicine syringe or similar and fill with mineral oil.
4. Attatch syringe and tubing to bleed nipple at caliper taking care to avoid air in tubing.
5. Open bleed nipple and inject mineral oil till reservoir is full.
6. Remove oil from reservoir.
7. Repeat 3 to 6 till you have clean oil with no air bubbles.
8. Brim reservoir with oil, close bleed nipple, replace top cap.
9. Replace wheel and pump brakes a few times. Should be all sorted.

tnwoolley

Interestingly when I got the bike out to check the brake line bolt at the reservoir (ta tony.w) the lever felt a bit stiffer. Held the lever back for an hour or so with some elastic bands and now I think its working pretty well.

Cheers everyone. Will try harder/be more patient next time.

bobbydickjohnson

Over new years, I put my bike into a LBS to have some new bits added and get it out the way while I moved apartment. Among the new parts was a Shimano Deore front disc. I got the bike back and the lever feel was spongey, it came into the handlebar. I pointed this out, the mechanic said it just needed wearing in and that it wasn't air in system, but Shimanos new modulation spring... I wasn't up to date on new bike technology after concentrating on studying/pursuing women etc, so gave him the benefit of the doubt. Rode about, pads broke in, and still brake performance was v poor, <40% that of my old, cheap Diatech Anchors, the lever feel was spongy. Put bike back to shop, they rebled it begrudgingly. Picked bike up, lever was still spongy. They said nothing was wrong with it, to which I offered to take a gamble and demonstrate that I could cycle flat out in front of shop and pull lever on full (with a bit of leaning back) and I wouldn't go over the bars. As I thought, the brake was still pathetic. They rebled it on the spot, This made it worse, I got a refund and fell out with that particular shop.

Today I took delivery of a new SLX front brake from Evans shop in Waterloo. It feels spongy too. Not as bad as the Deore, but pretty boaby. I just wanna ride the bloody thing.

Can anyone recommend somewhere in London where I can get this brake bled by someone who is familiar with these fiddly brakes?

cooldad

They are about the simplest brakes to bleed, and not at all fiddly. Any bike shop should be able to do it.
But no way should they need bleeding out of the box. Probably just needed a few minutes riding.

And awesome thread resurrection.