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Kelly over at Trackstar got my parts in to fix my MC on Monday. I also ordered a SS line and adjustable shorty levers. I picked them up on Wednesday and swapped them out the next day. I used my little vacuum pump to clean out my old MC and line. I pulled them off and put the new parts on. Then I used a giant syringe and back filled the system. I re-attached the vacuum pump to get the air out of the top of the caliper. I sucked out a bunch of bubbles and after several minutes of vacuuming the bubbles were still coming. I decided to try it the old fashion way and pumped my lever while opening and closing the bleeder valve. I did this for a long time and no bubbles were coming out. I put the cap back on the MC and take it up and down the street. The brake feel is terrible. Very squishy. What further steps can I take to finish bleeding my brakes?
 

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Stick a hose on the bleeder and put it in a glass jar. Fill the master and pump it with the bleeder open. Keep the master filled so you get no air in the system. Do not close the bleeder at all just let it flow fluid rapidly, but keep the master from going empty.

regards
Badger
 

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And leave it overnight with the cap off.
 

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And leave it overnight with the cap off.
Aufitt has got it except he left out 2 important points. Make sure the master cylinder is level, and, tie off your front brake caliper with something in the squeezed position else the air will just get trapped UNDER the check valve in the master cylinder.
 

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30 years working on cars here. The fluid accumulating in the glass jar will keep any air from getting back into the circuit. On the 90-96 300ZX Nissans we could not get the clutch bled using normal procedures. Also on my 76 280Z rear disc brake conversion.
It was due to lines that had upward loops and allowed the air to accumulate in the high spots. Normal bleeding would just not get that air out of the system. The power flush method worked perfectly in every case when normal procedures would not get the job done.

Allow enough fluid to accumulate in the glass jar to keep the end of the hose submerged so it can not let air back into the system. Using the process I recommended earlier I have flushed 4 wheel automotive systems by myself with 100% success.

If the fluid is clean in the jar, you can pour it back into the master cylinder to save fluid if necessary. Just make sure the end of the hose is always submerged in some fluid to act as a check valve to keep air from back flowing into the circuit.

regards
Badger
 

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30 years working on cars here. The fluid accumulating in the glass jar will keep any air from getting back into the circuit. On the 90-96 300ZX Nissans we could not get the clutch bled using normal procedures. Also on my 76 280Z rear disc brake conversion.
It was due to lines that had upward loops and allowed the air to accumulate in the high spots. Normal bleeding would just not get that air out of the system. The power flush method worked perfectly in every case when normal procedures would not get the job done.

Allow enough fluid to accumulate in the glass jar to keep the end of the hose submerged so it can not let air back into the system. Using the process I recommended earlier I have flushed 4 wheel automotive systems by myself with 100% success.

If the fluid is clean in the jar, you can pour it back into the master cylinder to save fluid if necessary. Just make sure the end of the hose is always submerged in some fluid to act as a check valve to keep air from back flowing into the circuit.

regards
Badger
This is "unconventional" how? That's the only way I've ever bled brakes
 

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Slipping a transparent tube onto the bleed nipple and running it UP into the master cylinder allows the pumped out (bled) fluid to return to the master cylinder. As this sort of pipe has a larger diameter than the brake line, it also gives an idea as to how much fluid as been circulated through the line.
 

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This is "unconventional" how? That's the only way I've ever bled brakes
The real question is, does it help the OP solve his problem?

I did it on a 73 Alfa Romeo I bought at a salvage auction in 1976 and drove it a 100k before I sold it. Best way to change fluid with my own two hands.

35 years ago

Started driving in 1966.

45 years ago.

regards
Badger
 

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30 years working on cars here. The fluid accumulating in the glass jar will keep any air from getting back into the circuit. On the 90-96 300ZX Nissans we could not get the clutch bled using normal procedures. Also on my 76 280Z rear disc brake conversion.
It was due to lines that had upward loops and allowed the air to accumulate in the high spots. Normal bleeding would just not get that air out of the system. The power flush method worked perfectly in every case when normal procedures would not get the job done.

Allow enough fluid to accumulate in the glass jar to keep the end of the hose submerged so it can not let air back into the system. Using the process I recommended earlier I have flushed 4 wheel automotive systems by myself with 100% success.

If the fluid is clean in the jar, you can pour it back into the master cylinder to save fluid if necessary. Just make sure the end of the hose is always submerged in some fluid to act as a check valve to keep air from back flowing into the circuit.

regards
Badger
Exactly where in this post is the word "unconventional" that you used, in quotes, indicating that is what I posted.

Nowhere.

regards
Badger
 

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If you havn't fully bled it yet? you could try a reverse bleed...
get a 10ml syringe with a bit of pipe the same dia as brake bleeder nipple and attach to syringe, draw up 10ml of fluid attach to brake nipple, crack it and inject it (slowly), then lock again, just make sure your master cyl is low to start with.

Be very careful none is spilled, so lots of rag around the Master cyl area.
 

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Unless its ABS?
 

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Kelly over at Trackstar got my parts in to fix my MC on Monday. I also ordered a SS line and adjustable shorty levers. I picked them up on Wednesday and swapped them out the next day. I used my little vacuum pump to clean out my old MC and line. I pulled them off and put the new parts on. Then I used a giant syringe and back filled the system. I re-attached the vacuum pump to get the air out of the top of the caliper. I sucked out a bunch of bubbles and after several minutes of vacuuming the bubbles were still coming. I decided to try it the old fashion way and pumped my lever while opening and closing the bleeder valve. I did this for a long time and no bubbles were coming out. I put the cap back on the MC and take it up and down the street. The brake feel is terrible. Very squishy. What further steps can I take to finish bleeding my brakes?
The brake fluid on a CBR250R Combined ABS model has to be changed / bled in a different way as on a non ABS model! It is not enough to do it the common way, only just by pumping.

Take a look at my thread, please:

http://www.cbr250.net/forum/cbr250-service-maintenance/8705-how-change-brake-fluid-cbr250ra-cbr250r-combined-abs-model.html
 

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Kelly over at Trackstar got my parts in to fix my MC on Monday. I also ordered a SS line and adjustable shorty levers. I picked them up on Wednesday and swapped them out the next day. I used my little vacuum pump to clean out my old MC and line. I pulled them off and put the new parts on. Then I used a giant syringe and back filled the system. I re-attached the vacuum pump to get the air out of the top of the caliper. I sucked out a bunch of bubbles and after several minutes of vacuuming the bubbles were still coming. I decided to try it the old fashion way and pumped my lever while opening and closing the bleeder valve. I did this for a long time and no bubbles were coming out. I put the cap back on the MC and take it up and down the street. The brake feel is terrible. Very squishy. What further steps can I take to finish bleeding my brakes?
Here is what I assume:

There must be brake fluid in the ABS valve unit, so you have to open the valves and pump out the fluid, which is inside the unit.

I suppose air has come into your valve unit and to pump it out, you have to open the valves first, for example by short-circuiting the valve unit. If you don't do that you will pump out the fluid and air out of the hoses, but not the ABS unit. Air will stay inside. The same with changing the fluid, the old one will stay in the ABS unit.

But that is only an assumption and I won't give anybody advice how do do something if I am not 100% sure, and that's the case here.

I hope someone in the forum knows how to change the brake fluid in a CBR250R Combined ABS model, respectively bleed it, and will specify a description.
 
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