Rear brakes

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I went to the abs block, loosen the connecting hoses from the block.

1st the master cylinder, pressed on the brake loosened the hose bolt and oil came out and the brake lever tightened, did this two time. I am now back to where I started from. Brake lever has no travel. by that I mean stuck or frozen no movement. I found the hose going to the rear brake cylinder loosened it up and nothing came out.

Also before i did the bleeding of the hoses I bled the front brakes, every looks good there.

I think I know where this is going but any input to differ I will try.

 
I went to the abs block, loosen the connecting hoses from the block.

1st the master cylinder, pressed on the brake loosened the hose bolt and oil came out and the brake lever tightened, did this two time. I am now back to where I started from. Brake lever has no travel. by that I mean stuck or frozen no movement. I found the hose going to the rear brake cylinder loosened it up and nothing came out.

Also before i did the bleeding of the hoses I bled the front brakes, every looks good there.

I think I know where this is going but any input to differ I will try.
RUH-ROH!

scooby_doo_scared.jpg


 
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I went to the abs block, loosen the connecting hoses from the block.

1st the master cylinder, pressed on the brake loosened the hose bolt and oil came out and the brake lever tightened, did this two time. I am now back to where I started from. Brake lever has no travel. by that I mean stuck or frozen no movement. I found the hose going to the rear brake cylinder loosened it up and nothing came out.

Also before i did the bleeding of the hoses I bled the front brakes, every looks good there.

I think I know where this is going but any input to differ I will try.
OK, so what happened is that when you loosened the hose from the master and pumped the pedal you purged any air from the line. Now when you attempt to push the pedal it is hydraulically locked. There is something blocking the flow inside the ABS Hydraulic unit, but just in the rear brake circuit.

Here's the diagram of the 1st Gen ABS

ABSHydraulicUnit.jpg


It's pretty much got to be item #6 - The Hydraulic control valve, and it must be stuck in the actuated position, which is where it goes instantaneously when it detects wheel slip. The block really can't be disassembled or repaired. You could try to activate the solenoid a few times and see if it will come loose, but I would think that you are going to need a new Hydraulic unit.

BTW - There have been some others who have had this valve stick on them, but it has always been in the default position, where you still get normal braking but no ABS action. You seem to be the first who has had one stick in the closed position.

 
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I went to the dealer and found the price for a new block, $1300.00 I sure am going to enjoy taking this out and finding out what makes it work.I dont think I have any ting to lose.

I'm looking at having a spool piece machined at work and remove the rear ABS. Leaving the front intact.

 
I went to the dealer and found the price for a new block, $1300.00 I sure am going to enjoy taking this out and finding out what makes it work.I dont think I have any ting to lose.

I'm looking at having a spool piece machined at work and remove the rear ABS. Leaving the front intact.
If you wanna keep your ABS functional on the front, don't screw with the metering block, if that appears to be the problem.....just run a brake line direct from the rear master to the rear caliper. Just bypass the ABS...no machining needed...just a new piece of brakeline.

 
Before I would entertain the idea it was Item #6 I would do one more testing.. I would try to push some air through the brake line and check all the electrical componets and connection before I spent $1300.00. I would lower the air pressure down to about 10psi and go no higher than 20 psi. make sure yo have your key turned on do there is power and i would also step on the rear brake pedal to make sure the air flows through...

 
If you wanna keep your ABS functional on the front, don't screw with the metering block, if that appears to be the problem.....just run a brake line direct from the rear master to the rear caliper. Just bypass the ABS...no machining needed...just a new piece of brakeline.
You might even be able to join the two ends of the existing rear brake line together, after disconnecting both at the hydraulic block, just using a double long banjo bolt and a nut?

Before I would entertain the idea it was Item #6 I would do one more testing.. I would try to push some air through the brake line and check all the electrical componets and connection before I spent $1300.00. I would lower the air pressure down to about 10psi and go no higher than 20 psi. make sure yo have your key turned on do there is power and i would also step on the rear brake pedal to make sure the air flows through...
I think that has all been tested, but using brake fluid instead of air.

But one thing that may free up the stuck rear brake spool valve would be sending pressure backwards through that rear brake circuit. In other words, hook the brake lines up backwards and press the brake lever.

 
....one thing that may free up the stuck rear brake spool valve would be sending pressure backwards through that rear brake circuit. In other words, hook the brake lines up backwards and press the brake lever.
Dang, Fred, that's a helluva idea!

 
Well I swapped the master cylinder hose to reversed the flow,Ignition was turned on, and fluid came out, slow but it was moving. pump a bowl full through it backwards.

returned the hose to there correct positions, and no good! Bummer!!Going to make sure the electrical is working, after that I am going to purchase a hose for a none abs and plug the other lines and start riding again.

Surgery tomorrow, need to be there by 5:00 am. Have to start my clean out procedure right now, if you don't know what that means you are lucky.

Glen

 
Damn!! I sure was hoping that we could get that thing freed up for you.

I'm sure that you can use the rear non-ABS as you are planning, but you're gonna want to fix it eventually, right?

So listen everyone... I know that ratman hasn't asked for anything other than for some technical advise with his problem. And although he's a long time member here (joined back in '05), he hasn't been a real active one. But we are a forum community, aren't we? And here's a guy that is obviously going through a lot in his life, he sure doesn't need this kind of crap from his bike.

Does anyone have a known good first gen ABS hydraulic block laying around that we could get some folks to chip in on and buy for the ratman?

Either that or we could just find one on fleaBay, but then there is no guarantee it would work when he got it. There are two units on fleaBay right now, but they are both for a second gen, and I don't think they are the same since the part numbers are different (first gens are 5VS-85930-09-00 and 2nd gens are 3P6-85930-09-00). One has a buy it now of $200 and the other is $700 (which seems a bit wacked)

edit - looking at the parts breakdown pictures they are definitely different. Probably due to the linked brakes on the 2nd gens.

I'll pledge $25 toward a replacement unit. Who else wants join in? You know it will make you feel good!! :)

And ratman, don't go thinking too much about my little proposal. It's the kind of thing that we do here on occasion. We've done it with whole engines and even entire bikes before. So please, just roll with it, OK? ;)

 
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The Gen II linked brakes ABS unit has 1 rear input from the master cyl, and 2 outgoing. One goes to the rear caliper, the second goes to the front (unified brake) piston. I don't know if it would work right if the unified brake port was plugged.

 
Damm guys, I just need some input, great offer but let it go towards some body or some thing that needs it worse then me. I hope to be done with my C and moving on..

I'm putting on a new hose and plugging the abs module. I will be quite good with that.

Can't work on it for awhile, but can't ride it ether.

Thanks again for the kind juster.

I am humbled...

 
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