brake bleeding

[RecentConvert]

During a brake fluid flush and installation of new pads, I have lost most of my front brakes.  Thinking I somehow introduced air into the system I started the bleeding process.  No speedbleeders and no vacuum.

 

I have now bled them multiple times and still have excess lever travel to engage the brakes, and they are very soft once engaged.  The lever very nearly hits the grip.

 

1. I have bled them from the top pulling the lever, opening the bleeder, closing the bleeder, releasing the lever, repeat.    Left caliper first, then right caliper.

2.  Pushed fluid from the calipers, pump them tight, spread pistons, pushing fluid back to the reservoir.

3.  Repeat #1, but inserting a step to push back from the calipers.

4.  Use GS911 to bleed the ABS.  That procedure includes repeating #1

5. Repeat #4.

 

I've used 24 oz of brake fluid so far.

 

I still can pull the lever nearly to the grip.  I have brakes but lots of lever travel and they are soft.  I've taken some short test rides between bleedings.

 

I haven't seen a bubble in the clear tubing since the first attempt.

 

What am I overlooking?

 

[Cap]

49 minutes ago, RecentConvert said:

What am I overlooking?

 

 

Maybe they are fine, but the pads are backed away from the rotors?  In that case, you need to pump the lever until the pads are reseated against the rotors, at which point the lever will feel solid.  

 

I do this every time I swap the front wheel, and need to back off the pads first.  

 

Cap

[Hosstage]

Try tying the brake lever to the bar overnight.

[Zara]

Almost every brake bleed I've done have been spongey at first,  Like Hosstage metioned.  I tie the lever back and leave it overnight that way if i see the reservoir is really low in the morning i can look for a leak.

[Motorhead1977]

If you somehow have some air in the system pulling the lever back to the bar and zip tying it in that position can allow any bubbles to travel up to the reservoir. Let it sit for up to 24 hours, then check. I've done this successfully many times. Good luck.

[dirtrider]

18 hours ago, RecentConvert said:

During a brake fluid flush and installation of new pads, I have lost most of my front brakes.  Thinking I somehow introduced air into the system I started the bleeding process.  No speedbleeders and no vacuum.

 

I have now bled them multiple times and still have excess lever travel to engage the brakes, and they are very soft once engaged.  The lever very nearly hits the grip.

 

1. I have bled them from the top pulling the lever, opening the bleeder, closing the bleeder, releasing the lever, repeat.    Left caliper first, then right caliper.

2.  Pushed fluid from the calipers, pump them tight, spread pistons, pushing fluid back to the reservoir.

3.  Repeat #1, but inserting a step to push back from the calipers.

4.  Use GS911 to bleed the ABS.  That procedure includes repeating #1

5. Repeat #4.

 

I've used 24 oz of brake fluid so far.

 

I still can pull the lever nearly to the grip.  I have brakes but lots of lever travel and they are soft.  I've taken some short test rides between bleedings.

 

I haven't seen a bubble in the clear tubing since the first attempt.

 

What am I overlooking?

 

Morning  RecentConvert

 

That's the problem with doing more than one thing at once, you now don't know if your problem is due to the bleeding process or due to  the new pads. 

 

If you have bled it that many times, using that much fluid & are not seeing any signs of air then that points to the pads, not the bleeding, as the problem (not 100% but good chance the pads are the issue).

 

New pads can be springy until fully bedded in & all the pad fluff is gone.

 

If you have enough lever force to stop the motorcycle (ie lock the front wheel at speed) then just riding the motorcycle for a few hundred miles using lots of normal braking will probably bed the pads & gain you less lever travel & a firmer lever)

 

Or, if you want to determine what is/isn't causing the problem then just toss the old pads back in, ride it a few miles then see if your lever feel/ lever travel returns to normal.  

 

If it does then the pads were the issue & your problem with the new pads will probably subside with normal brake usage & pad break-in.

 

If you STILL have the excess lever travel & a spongy lever with the old brake pads after a couple of short rides  then look to how you might have gotten  air into your brake system.

[RecentConvert]

The zip ties made a major difference!  I don't know why, but after 8 hours, the lever is firm and engages further out.  Not quite where I started, but a lot better than when I gave it up last evening.

 

I would like to get the lever a bit quicker to engage.  Dare I bleed them a bit more?  Should I quit before I lose what I have regained?

[Motorhead1977]

31 minutes ago, RecentConvert said:

The zip ties made a major difference!  I don't know why, but after 8 hours, the lever is firm and engages further out.  Not quite where I started, but a lot better than when I gave it up last evening.

 

I would like to get the lever a bit quicker to engage.  Dare I bleed them a bit more?  Should I quit before I lose what I have regained?

Try zip tying the lever overnight again. You may get more improvement. That's also worked for me.

[AndyS]

On 6/16/2020 at 2:08 AM, RecentConvert said:

  Dare I bleed them a bit more?  Should I quit before I lose what I have regained?

The question is...do you NEED to bleed them any more or are they working? Have you not got the brake feel you are looking for? Do they feel spongy, Do they fade?

 

If the answer is yes, then you need to continue. If not, you are good to go.

 

Bear in mind you have new pads fitted, so these will take a good while to bed in and then your braking performance will continue to increase as these settle in.

 

 

[szurszewski]

If you’ve got it working pretty well I’d ride it a few hundred miles and try to get the brakes a good workout. That may help you move any remaining air around. Only then would I consider bleeding again.