[Jim O]

I searched for this but could not find the answer so here goes. I am about to inspect the pads on my front disc brakes and likely replace them. I have read in a lot of places that when I push the pistons back in to make room for the new (thicker) pads, the brake fluid may leak from the resevoir. What is not said is whether or not I am to remove the top of the resevoir before doing this work. It seems that I should but I'd like to know for sure.

Thanks!

 

[Nehalem Dave]

No. You crack the bleeder valve on the wheel end, then push the pistons out. Use a tube to route the fluid and keep out air -fluid is corrosive and toxic. Close the bleeder. After installation, and actuate the brakes till they seat then add fluid to the well as needed. Bleed system if brakes are spongy.

 

[vgreid]

I picked up a tube at the dealer that has a one-way check valve in it to keep air from going back into the line through the bleeder valve. You might want to consider something similar.

 

[oconeedan]

Nehalem Dave, I never did it that way, although maybe it is the correct way?

I remove the master cylinder cover, as you have to do that anyway, draw off some fluid with syringe. Squeeze pistons in the calipers, the fluid has to go somewhere so it goes back into master cylinder.

I suggest, when changing brakes, and since you will have to adjust the level of the fluid, go ahead and flush the brakes from master cylinder down to the bottom to the caliper. Too easy to do, you already opened a new bottle of DOT 4 brake fluid, right? And you are going to throw away the bottle when done, right? (I never use fluid from an open bottle, always open a fresh bottle since it's hygroscopic). Too cheap to not flush it.

I bleed the traditional way, squeeze lever, open bleed valve while squeezing, close valve, then release lever. You can reach both at the same time, easily. You can do the same with rear brake too.
Dan

 

[gat803]

If you haven't added any brake fluid since the last time new pads were put on the bike, there is no reason to bleed any fluid off.....it won't leak from anywhere when you push the caliper pistons back in.

 

[Scrapdog2grand]

If you haven't added any brake fluid since the last time new pads were put on the bike, there is no reason to bleed any fluid off.....it won't leak from anywhere when you push the caliper pistons back in.

No disrespect, but the fluid is hydroscopic, its designed to absorb moisture and disperse it throughout the system. honda recommends bleeding the system every 2 years for the bikes, every 3 for thier cars. I personally bleed them every year. Its cheap, and my brakes are very important to me .
1 moisture in the fluid reduces the boiling temp of the fluid.
2 the miosture can create problems within the system, deteriorate the system from the inside, corrosion things like that.

with the synthetic fluids dot5(which has a higher boiling point)the moisture does not disperse throughout the system but settles, and causes similar problems, within the system. something like that.

 

[Nehalem Dave]

Ditto ScrapDog's comment. I don't grasp why people resist losing 25 cents worth of fluid - I am a cheep skate too but, come on. The bleeder approach is an old habit with me from dealing with larger systems and check valves which allow small amounts of fluid to reverse but slam shut for larger volumes or higher pressures.

When I change pads, the entire system gets bled whether it likes it or not and usually the dark color coming out is witness as to why it was a good idea.

 

[wallasan10]

If you haven't added any brake fluid since the last time new pads were put on the bike, there is no reason to bleed any fluid off.....it won't leak from anywhere when you push the caliper pistons back in.

+1
That’s the way I do it too. I ride a lot and go through a lot of pads.
Every time you open the system you let a little moisture in.
If I only put new pads on every couple of years maybe I’d feel differently.

 

[Frogman172]

If you get new pads, you dont need to bleed the brakes. Just do as oconeedan said. Take off the reseviour. Suck some shat out with a turkey baster or somn. Put a flat head screwdriver in there and push the old pads apart to give you room on new pads. Make sure you put a rag or towel down under your reseviour in the event it spills over it doesnt screw your paint job up. Brake fluid is pretty corrosive. If you want to be even more Johnny on the spot take some sand paper and scorch up you rotor brake on both sides. Take your new pads and scratch them on the deck of a hard concrete floor. Throw those bitches on and pump your pads. Drive fast and jam on those brakes a few times at different speeds. Do that for a few minutes and your done. No drama. Do replace your brake fluid sometime. If its brown its time. I got speed bleeders. Easy peasy with speed bleeders. No worries. Use the new brake fluid when you replace it. Have fun. Its not all that hard. Now go ride!

 

[Lakota]

What Frogman said: Speedbleeders.
-john

 

[Scrapdog2grand]

What Frogman said: Speedbleeders.
-john

I personally use a soda bottle with a hole drilled in the top, and stick a piece of vecuum line in it till its just off the bottom. you have to add a little fluid to the bottle so the end of the vacuum line is submerged, works great. I'm not familar with the speed bleeder but I will look into them. Do they come chromed?

 

[gat803]

The question wasn't "Should I change my brake fluid?" For the question, as asked, my answer is correct.

I'm all for changing brake fluid when it needs to be changed, but that wasn't the question johern posed.

 

[Jim O]

I bought this bike in the summer of '09 and the brakes have never been bled. I will do that at the same time I replace the pads. Thank you to everyone for their suggestions. Damn, I love this site!

 

[Scrapdog2grand]

The question wasn't "Should I change my brake fluid?" For the question, as asked, my answer is correct.

I'm all for changing brake fluid when it needs to be changed, but that wasn't the question johern posed.

Agreed! see how easy it is to get taken off the subject. Still a good idea to bleed it while your there.
I always seat the pads with a dozen or so low speed stops with firm braking.
You dont want to over heat them while seating them.
this is what I do with my Wifes bike/car, or a customers car, dont nessicarily do this with my own stuff