[j.les]

I bought my XT's last year and they're due for a bleed. Thing is I haven't bought a bleed kit yet. Can you just use the funnel to bleed them? My last set of Shimanos were bled by simply removing the reservoir cover and adding mineral oil. Was hoping I can just purchase the threaded cup thing and avoid buying a whole bleed kit.

 

[aerius]

Can be done. But will likely result in lots of cursing and thrown objects.
I've done it once before, I don't recommend trying it.

 

[One Pivot]

You can pickup a huge 30ml syringe from the grocery store in the baking section. They're used for injecting crap into meat. I think I paid 4 bucks. The little bike specific squeeze bottles really suck, and the bike specific syringes are the exact same thing but marked up.

aerius is right, dont bother trying without a syringe.

 

[Aglo]

I never have done it with the funnel. I brought a syringe from a local pharmacy zip tie a plastic hose to it and done. Total cost 3€, and a 100% success rate on the bleed.
But due to my Formula brakes I'm used to bleed with syringes, so if its your first time, maybe you will need a second try, but I bet you will do it in the first attempt.

 

[gbug]

Hmm, some interesting responses so far, or at least interesting to see what others are doing. With Shimano brakes, you don't necessarily need a syringe, in fact I have never used one on my XTs. For a full servicing, I do a gravity bleed on the lower caliper first, then a bleed at the lever using the funnel. If you are in a hurry and your brakes aren't horribly spongy, you don't even have to mess with the caliper, just do a bleed at the lever using the funnel.

 

[Cleared2land]

With Shimano brakes, you don't necessarily need a syringe, in fact I have never used one on my XTs. For a full servicing, I do a gravity bleed on the lower caliper first, then a bleed at the lever using the funnel. If you are in a hurry and your brakes aren't horribly spongy, you don't even have to mess with the caliper, just do a bleed at the lever using the funnel.

There's some misleading information being provided here. This can only be partially correct if the location of the air introduction is close by what you're attempting to do. If you've got air in your caliper and that's the source of the spongy brakes, chances are, conducting a 'Funnel Only Bleed' just isn't going to work.

Make life easier and bleed in the direction of the air source.

 

[gbug]

There's some misleading information being provided here. This can only be partially correct if the location of the air introduction is close by what you're attempting to do. If you've got air in your caliper and that's the source of the spongy brakes, chances are, conducting a 'Funnel Only Bleed' just isn't going to work.

Make life easier and bleed in the direction of the air source.

Agreed, that's why I made it a point to say for a full bleed do both a gravity bleed and a funnel bleed.

 

[frdfandc]

Funnel on the master cylinder. Syringe on the caliper. Push fluid in from the caliper side into the funnel. That's how I bleed my SLX brakes.

 

[Mr Pig]

If I had to do without a plastic object it would be the funnel, not the syringe. I've bled them without the funnel but refusing to buy a syringe for a few bucks is just obtuse.

 

[gmats]

Yes, it is possible. Cars are bled this way. The trick though, is to keep enough fluid in the master cylinder such that you don't introduce more air into the system. I have done this in a pinch with various brakes (Avids, Shimano, Hope). The other problem is being very careful not to leak fluid on to your caliper and contaminating the pads. Use a clear hose like those from aquarium air pumps. Use a small container to submerge the line in. Hope that helps. It's not the ideal way to do it but in a pinch, it'll work.

 

[Cleared2land]

If you elect to use a hose, remove the brake pads to ensure no fluid contamination.

 

[D Bone]

I only do my SLXs with the funnel, just like any other hydro brake system. I use a short piece of tubing with a plastic baggie taped to one end, and attach it to the bleed port. Then I screw the Shimano funnel into the reservoir and fill it up about 1/4 of the way, and then bleed....... My brakes are rock solid with zero issues.

Like this:

 

[jonshonda]

Yes, it is possible. Cars are bled this way.

lol wut?

I don't know how you bleed cars, but the syringe in this case is acting like the brake pedal in a car. You are forcing fluid into the system, which forces air out. Doing a bleed w/o some type of force to drive air out is not actually a bleed.

 

[D Bone]

lol wut?

Pressing the brake pedal in a car is the same as pulling the brake lever on the bike. The Shimano funnel on the bike acts as nothing more than a "reservoir extension" that prevents the reservoir from running out of fluid, and inducing air into the system.

 

[Cleared2land]

Some seem to get a little confused on this.

Pretty simply really...

Use of brake lever to force fluid down and out of caliper.

Use of syringe to bleed upwards and out of master cylinder.

I try and bleed in the direction of the air to minimize time and fluid needed to bleed. Keep it simple.

 

[gmats]

lol wut?

I don't know how you bleed cars, but the syringe in this case is acting like the brake pedal in a car. You are forcing fluid into the system, which forces air out. Doing a bleed w/o some type of force to drive air out is not actually a bleed.

The OP asked if this was possible. I know millions of people have bled brakes over generations by adding fluid to a master cylinder of a car and individually bleeding each of the brakes at each of the corners of a car. Is it the best way to bleed the brakes on a bike? No, not really but will this method work (only the funnel?). Yes, it will.

 

[KevinGT]

When you say "funnel only" are you talking about just filling the funnel, screwing into the master cylinder, and then opening the bleed port of the caliper to let gravity push fluid out (into a tube)?

 

[D Bone]

I don't believe that's what the OP had in mind.

1) remove wheels, remove pads, insert bleed block
2) attach funnel to reservoir and fill 1/4 with fluid, repeatedly flick the lever fast to burp any air in the reservoir / lever
3) attach hose / baggie to caliper bleed port
4) with bleed port closed, pull lever
5) while holding lever, open bleed nipple, lever collapses to grip as fluid and air is pushed out the tube, don't let go of lever
6) while still holding lever all the way to grip, tighten bleed nipple, release lever
7) check fluid level in funnel, fill if needed, tap caliper & brake line with something firm that won't scratch to release any air
8) again repeatedly flick lever fast to burp any air in reservoir / lever

9) repeat entire process until no air is seen in the tube, or coming into the funnel

After shortening my lines, I saw no air after the 2nd pass, yet I did about 8 more as to make sure I got it all. Both brakes combined took less than 5 minutes to do 8-10 passes each. Brakes are rock solid and have been for their entire life.

 

[Cleared2land]

D bone's shortening of the brakes lines is a classic reason to use a syringe and bleed up towards the master cylinder where the air was introduced.

Obviously, as D bone has articulated, it's an easy enough task to do in the downward direction if that where your comfort level is.

My logic is to bleed in the direction that's closest to where the air was introduced.

 

[D Bone]

Totally agree C2L. Had I of had the proper syringes, I probably would've done the Shimano preferred method, but I didn't, and my LBS gave me the Shimano funnel and I knew it could be done, so that's what I went with.

That being said, I was amazed at how much air came out of the funnel when I did the very first "flick of the lever" before ever cracking the bleed nipple. From what I saw, and the way the lever felt immediately after, I could've just called it a day there as I bet I got 95% of the hose shortening induced air out.

Along those same lines, after the 1st bleed, I had my wife tap on the caliper and then along the entire length of hose up towards the lever as I flicked the lever and that alone got more air out than the 1st bleed did.

Now I do the same thing after replacing pads (and having to open the reservoir to reset the pistons) and I usually get 1 small bubble out per brake........ EZ PZ