Brake Bleeding Tip

[RJ]

I recently did a GSXR front end swap on my '82 1100E. As part of the deal I bolted up the 6 piston Tokico calipers. Even using braided steel brake lines I could not get all of the mushiness out of the brake lever after bleeding. Long story short, I removed the pads, stuck a large screwdriver (gently) in between the rotor and pistons, and twisted the screwdriver towards the pistons to push them deep into the calipers. I did this with all 12 pistons, replaced the pads and wow, brakes are now totally mushy even though I did not crack open the bleeder valves or brake lines. I bled the brakes one last time and bingo hard as a rock brake lever. Moving the pistons back and forth released air that was trapped in some corner of the calipers that bleeding with pads in place could not have dislodged. I LOVE these brakes now. This same technique can be used on any other type of caliper, mine probably have more spaces to trap air into than calipers with fewer pistons. Good luck!

[8trackmind]

I'm going to try this.
I have been bleeding mine all day and still have a mushy lever. The thing is, I know the master is good because running one caliper, it does fine. Rock hard in fact.
When I swapped to two, single piston calipers, mush.
I'm using a 97 Katana master.

I even bought a vacume bleeder. Still mush.
Bench bled the master. Still mush.
Bled every fitting starting from the master down. Still mush.
Tied the lever up and left it overnight. Still mush.

Frustrating to say the least.

[mlaalm]

Thanks for sharing, I have the exact same setup and still have 'that mush'ie feeling'. Never thought about doing such. Appreciate - Mike

[Nerobro]

Yaknow, I have the same problem. I'm going to try the "pushing the pistons out" trick with skreemers and my bike.

I still need to post pictures for ya 8track...

[mhardig]

Easy power brake bleeder

I had trouble with my old Land Rover until I figured out how to power bleed brakes. It's incredibly simple and cheap to do.

1: Get spare master cylinder cover and gasket.
2: Attach hose barb to spare cover and plug any other holes.
3: Buy new cheap plastic garden sprayer
4: remove nozzle from garden sprayer and attach to spare cover hose barb
5: Fill sprayer with proper brake fluid. Put spare cap on master cylinder.
6: pump up sprayer a couple pumps
7: Bleed caliper. If necesary, remove caliper and invert and rotate to ensure all air is removed.

This worked like a dream on my old Land Rover. Never tried it on a bike, but i bet it would work as well.

[5RON5]

Bleeding tip!

Wow, this is a weird way to get the air out? Isn't it a lot of work? I mean, I take it, the sprayer is for a pressure or power bleed of the system? Glancing over the way to do it, I guess the pressure goes through in a hurry? Where did it say to hook it up to? It says to bleed the caliper. What does it mean when it says to invert the caliper to make sure all bubbles are out of it? Where exactly would I hook up the end of the hose, on the caliper? Is that where I would start the pressure bleeding from? Not the M C itself? Please don't think I am a bit, let's say, thick at times! I may be. Well, actually, pretty much of the time. Seeing a picture is usually the best way for me! HA! But I almost get it. This sounds like a pretty good way to go, if I can not find the problem by just looking at everything. Like the bulging lines. I thank you so much for giving me a way out with this, & for doing so, it is a way of saving me a lot of money I do not have! For that, I thank you greatly!

[Harvey Norman]

It looks like he's using the garden sprayer to pressurize the system instead of having to pump the brake lever. He gets two hands free this way.

[Nerobro]

I REALLY like this idea. time to buy a garden sprayer...

[mhardig]

it worked fine for my land rover

and I also use it to power bleed the brakes on my travel trailer every year. I have been very pleased with this very rube-goldberg device, let me know if it works as well on bikes.

As an aside, Snap On sells the EXACT thing, for $200. I have $9 invested in mine. Snap on uses an adapter that consists of a flat plate with one rubberized side, and a bunch of what looks like zip ties. I can see where this would work on a car, I don't know about a motorcycle.

http://buy1.snapon.com/catalog/item.asp?P65=&tool=all&item_ID=56237&group_ID=1671&store=snapon-store&dir=catalog

[Mike_H]

wow...thats a pretty good idea. thanks for the tip. I still wonder if that method would have gotten ALL the air out from behind all six pistons... Do you know how much pressure you can put on the system with a garden sprayer? Seems like the lever would give you more pressure. Maybe I'm missing something here.

[mhardig]

Pressure vs flow

You can empty a 3 quart garden sprayer in about two minutes with this method. I wouldn't pump it up too much lest you overstress the handlebar reservoir.

I always looked at it this way: someone lets a fart in a long hallway. What do you do, put a big fan with a lot of flow to clear the fart out, or close all the doors and pressurize the system and hope the fart escapes when you crack the door. The brake fluid flowing freely under low pressure carries bubbles along with it very easily, where with high pressure the bubble can stay stuck in one place. Just my humble opinion- but in the Land Rover with it's thirty-odd feet of line, it was a ginormous pain in the ass to bleed by hand, I did it with the pressure system, by myself,. in five minutes. Same with my trailer- I could get that thing bled and ready to go in no time at all.