[max05pointy]

Over the winter I decided to upgrade the stock brakes with braided lines and 4-pot 03 GXSR600 calipers. I also cleaned and rebuilt all the calipers on the bike just for good measure (BTW For those that don't have an air compressor, I managed to pop out all the caliper pistons using a regular tire pump). Now I have to fill the whole system (front and back) with brake fluid, and this is the only tool at my disposal: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=98864 So... SVers can you critique my plan and give me some pointers? I've never bled brakes before so the more details the better

Rear:
Crack the bleeder, and attach 'the tool' to it. Start pouring brake fluid in the reservoir while pumping the brake pedal. Once fluid with no bubbles comes out the other end, tighten the bleeder.

Fronts:
Crack one of the bleeders and attach the tool to it. Start pouring brake fluid in the reservoir while pumping the brake lever. Once fluid with no bubbles comes out the other end, tighten the bleeder. Repeat for the other side.

I'm pretty sure I'm missing something cause this seems way too easy ??? Help me out guys!

 

[SilverK3]

Might want to get a speed bleeder, otherwise you'll be pumping levers for hours

 

[andyauger]

You're on the right track, but a Mitey Vac would speed things up a good bit.

For dry systems what I sometimes do is pull the caliper and put a wood spacer between the pistons. Then lift the caliper as high as it will go, then start the bleed procedure.

Open bleed nipple, pull lever, close nipple, slowly release lever, repeat. You can close the nipple finger tight during the bleed.

 

[max05pointy]

For the purpose of this post, let's assume I have no access to any other tools. What's the best approach using what I do have? I don't mind pumping the lever for a while.

andy: How does lifting the caliper above the MC help? Do you still add fluid to the reservoir? Then what's forcing the fluid up the lines?? What's the advantage over the method I described above?

 

[krw]

I see where you are going with the check valve in your bleeder tube. The check valve will help, but don't count on it for the final few bleeds. Air often gets sucked back in around the tube where you hook it up to the bleeder. Use andyauger's method:

Open bleed nipple, pull lever, close nipple, slowly release lever, repeat. You can close the nipple finger tight during the bleed.

Raising the caliper keeps the air from going toward the M/C when you are trying to get it out of the bleeder on the caliper, if that makes sense.

 

[max05pointy]

I figured I'd put a hose clamp around the bleeder so no air will get in, but it can't hurt to use andy's method to finish it off.

Let me see if I understand this right so far:

With the system mounted on the bike - initially the entire system is filled with air and open on both ends (open bleeder on one end, open reservoir cap/pulled in brake lever on the other). As I start to pour fluid into the reservoir and it starts filling the lines it displaces the air, and the air takes the path of least resistance i.e. down the lines and out the bleeder. Since theres a 1-way valve on the bleeder air cannot get back in that way (assuming its airtight) so once solid brake fluid starts dribbling out the valve, all the air has to be gone and the system is completely filled. Pump the brakes a few times and top off the reservoir.

This seems like it would work great for the rear (with only one bleeder), but what about the fronts (with two bleeders)? I only have the one valve...

 

[nevenelestate]

This seems like it would work great for the rear (with only one bleeder), but what about the fronts (with two bleeders)? I only have the one valve...

do the two lines seperately, open left and bleed the air out, close the left repeat on right

 

[30x26]

another option:
buy a big syringe (60cc are enough), remove needle , adapt diameter with knife and slowly fill the system from the caliper. usually it works at the first attempt

 

[Northwind]

another option:
buy a big syringe (60cc are enough), remove needle , adapt diameter with knife and slowly fill the system from the caliper. usually it works at the first attempt

+1 million. This is actually the standard approach for bicycle disc brakes, bleeding upwards is better than downwards as air inherently wants to rise. My own approach is to push the fluid up til the bubbles stop, then push it back down using the lever- this'll dislodge some air usually- then repeat the original "bleed upwards" with the syringe to finish. Perfect results in about 2 minutes per side, every time. Far better than my Mityvac, which I now never use!

 

[PunkinDave]

You're on the right track, but a Mitey Vac would speed things up a good bit.

For dry systems what I sometimes do is pull the caliper and put a wood spacer between the pistons. Then lift the caliper as high as it will go, then start the bleed procedure.

Open bleed nipple, pull lever, close nipple, slowly release lever, repeat. You can close the nipple finger tight during the bleed.

+1...
Flush through at least one complete system's worth...

 

[Roadstergal]

another option:
buy a big syringe (60cc are enough), remove needle , adapt diameter with knife and slowly fill the system from the caliper. usually it works at the first attempt

That is absolutely the way to go. It eliminates the frustration I always used to get trying to fill a dry system from the top down.

I picked up a plastic syringe at the local hardware store. No modifying necessary - I fill it with brake fluid, stick it in the bleed nipple at the caliper, open the nipple, and fill that puppy. Keep going until fluid comes out at the reservoir. Just a quick bleed once it does to make sure all is copacetic, and you're done. As said before, it's making the air go up, the direction it wants to go.

 

[briderdt]

Edited because I realized it truly was a stupid question...

 

[herbn]

I set up a system with a brembo lever ,stock calipers, and braided lines. i used clear plastic syringes to try for suction and/or pressure to pump fluid in, i tried gravity feed,no amount of gravity feeding, pumping and opening and shutting the bleeder valves (on the calipers) did anything , Vacuum ,syringe suction on the bleeder valve of the lever finally got things started, less than five minutes later i was essentially done, i left everything hooked up and bled things a couple more times over the course of a few days, i have slight softness at the lever now that might go away if i bled things again but i like the position of the lever and the power of the front brake really is pucker inducing.

 

[max05pointy]

That is absolutely the way to go. It eliminates the frustration I always used to get trying to fill a dry system from the top down.

I picked up a plastic syringe at the local hardware store. No modifying necessary - I fill it with brake fluid, stick it in the bleed nipple at the caliper, open the nipple, and fill that puppy. Keep going until fluid comes out at the reservoir. Just a quick bleed once it does to make sure all is copacetic, and you're done. As said before, it's making the air go up, the direction it wants to go.

That does sound easier... What kind of syringe is this exactly, anybody have a link or pics? This thing is sold at home depot?

Doesn't air get in as you pump in brake fluid? I'd think just sticking the tip of the syringe in the bleeder isn't exactly airtight.

 

[Vspec]

Would this work with the ABS pump on an ABS model?

 

[BossMan]

That does sound easier... What kind of syringe is this exactly, anybody have a link or pics? This thing is sold at home depot?

Doesn't air get in as you pump in brake fluid? I'd think just sticking the tip of the syringe in the bleeder isn't exactly airtight.

I haven't tried this yet, but I am going to use a small amount of hose and hose clamps.

I got my syringe from mcmaster. it should be resistant to brake fluid.

 

[Roadstergal]

That does sound easier... What kind of syringe is this exactly, anybody have a link or pics? This thing is sold at home depot?

Doesn't air get in as you pump in brake fluid? I'd think just sticking the tip of the syringe in the bleeder isn't exactly airtight.

It's just a random plastic syringe I got at OSH. It isn't on their site, but it's a lot like a 10mL lab syringe with a tapered tip instead of a luer lock. I can take a pic tonight.

You don't stick just the tip into the bleed nipple; you shove it all of the way in and press hard so that the fluid goes up instead of dribbling out. Then air doesn't get in. I could make some really bad sexual metaphors, but I think you get the idea.

 

[mattsavage]

It's just a random plastic syringe I got at OSH. It isn't on their site, but it's a lot like a 10mL lab syringe with a tapered tip instead of a luer lock. I can take a pic tonight.

You don't stick just the tip into the bleed nipple; you shove it all of the way in and press hard so that the fluid goes up instead of dribbling out. Then air doesn't get in. I could make some really bad sexual metaphors, but I think you get the idea.

So I tried this method this evening. It seems like more fluid seeped back out of the caliper around the bleed screw than went up into the lines... I had it just barely loose, not even an 1/8th of a turn and I could see it just seeping out around the base of the bleed screw from the caliper... I've done this a hundred times on mountain bike brakes, never had this problem.

...Oh, and then my shim holding the pistons in place slipped out and piston popped, dumping all my fluid so I had to do it all again...

What a royal PITA....

 

[Northwind]

That can happen sometimes, if you want to stick with this method you can get a wee bit of plumber's teflon tape and wrap it round the threads- remember the threads aren't actually designed to be fluid-tight.

 

[Vspec]

For those using the syringe technique, has do you ensure you don't introduce air in the system? I see how I can make sure there is no air in the syringe but what about the tubing between the syringe and the caliper?