Is the rear brake this bad or is there something wrong with mine?

[navid]

I just got a used 2017 with 10k miles, so I have no gauge for the feel of new brakes on this bike. I heard bad things, but is the rear brake this horrendous? It feels like my brake lines are filled with air.

I have a solidly pressing on the rear and I get worse decel than just engine braking. Should I try bleeding my brakes or is this expected behavior for this bike's brakes? Any advice is appreciated.

[ElGonzales]

step 1)throw away the original Yamaha brake pads
step 2)install Brembo SA sinter pads. Or TRW sinter pads.
step3)do a brake in ride --> ooohh wow we have a working rear brake! 

[M. Hausknecht]

You should be able to lock the rear wheel with the rear brake. If you can't, try bleeding first. Then check to be sure the caliper is able to slide on the greased pins. If the caliper cannot slide, some disassembly, cleaning, and apply fresh grease. If that doesn't do it, clean the disc with brake cleaner and an abrasive pad, and replace the pads. HH pads are available from a number of manufacturers and are a step up from OEM pads without needing to be heated up first like more track-oriented pads.Having said all that, when serious slowing is necessary, the front brakes are multiples stronger (80%/20% is oft-quoted). The brakes on the 07 are just fine for street riding, but they do need periodic maintenance.

[navid]

1 hour ago, M. Hausknecht said:

You should be able to lock the rear wheel with the rear brake. If you can't, try bleeding first. Then check to be sure the caliper is able to slide on the greased pins. If the caliper cannot slide, some disassembly, cleaning, and apply fresh grease. If that doesn't do it, clean the disc with brake cleaner and an abrasive pad, and replace the pads. HH pads are available from a number of manufacturers and are a step up from OEM pads without needing to be heated up first like more track-oriented pads.Having said all that, when serious slowing is necessary, the front brakes are multiples stronger (80%/20% is oft-quoted). The brakes on the 07 are just fine for street riding, but they do need periodic maintenance.

Thanks for the advice. Yeah, I use front brakes for emergency braking. Back is just for slow speed turning and stop and go traffic.

[Triple Jim]

For reference, I can easily lock my rear wheel with stock pads.  You're probably right about air being in the system.

[fzar]

On 5/18/2024 at 10:16 AM, Triple Jim said:

For reference, I can easily lock my rear wheel with stock pads.  You're probably right about air being in the system.

That is the only straight forward description of what needs to be looked at First.

[navid]

On 5/18/2024 at 8:58 AM, M. Hausknecht said:

You should be able to lock the rear wheel with the rear brake. If you can't, try bleeding first. Then check to be sure the caliper is able to slide on the greased pins. If the caliper cannot slide, some disassembly, cleaning, and apply fresh grease. If that doesn't do it, clean the disc with brake cleaner and an abrasive pad, and replace the pads. HH pads are available from a number of manufacturers and are a step up from OEM pads without needing to be heated up first like more track-oriented pads.Having said all that, when serious slowing is necessary, the front brakes are multiples stronger (80%/20% is oft-quoted). The brakes on the 07 are just fine for street riding, but they do need periodic maintenance.

I bled the brakes. They were yellowish brown and had some bubbles. I cycled through fluid until the color was totally clear. However, I think the brake is still spongy.

The pads didn't reach the wear indicator by quite a bit. Is there anything else I can do? I am thinking of cleaning the discs and grease the calipers, but I don't see that being the reason for this much of a mushy feeling.

Edited May 20 by navid

[Claude]

Whenever I bleed brakes, I find a way to press the (front) lever toward the throttle overnight. Some air bubbles find their way to the master cylinder and the lever becomes firmer.

For the rear brake, I find a way (usually a bungee attached to my work table) to press on the brake pedal overnight with the same result than for the front.

[Triple Jim]

@navid, does this FZ have anti-lock brakes?

[navid]

47 minutes ago, Triple Jim said:

@navid, does this FZ have anti-lock brakes?

Yup, it's the ABS model. The service manual showed the same procedure.

[navid]

1 hour ago, Claude said:

Whenever I bleed brakes, I find a way to press the (front) lever toward the throttle overnight. Some air bubbles find their way to the master cylinder and the lever becomes firmer.

For the rear brake, I find a way (usually a bungee attached to my work table) to press on the brake pedal overnight with the same result than for the front.

Do you do that after you are finish bleeding and close the bleeder nipple?

Also, do you keep both brake reservoirs completely sealed while having them pressed?

[Claude]

8 hours ago, navid said:

Do you do that after you are finish bleeding and close the bleeder nipple?

Also, do you keep both brake reservoirs completely sealed while having them pressed?

Yes and yes.

[Triple Jim]

9 hours ago, navid said:

Yup, it's the ABS model. The service manual showed the same procedure.

With ABS brakes you need to run the pump when bleeding or you'll never get the air out.  Have you done that?

[navid]

53 minutes ago, Triple Jim said:

With ABS brakes you need to run the pump when bleeding or you'll never get the air out.  Have you done that?

Ah that must be it, I haven't done that.

[Claude]

10 hours ago, Triple Jim said:

With ABS brakes you need to run the pump when bleeding or you'll never get the air out.  Have you done that?

Strange as I bled both brakes on my 2017 ABS using the "standard" procedure and both are "rock solid" (if I can use that expression...).

Edited May 20 by Claude

[navid]

2 hours ago, Claude said:

Strange as I bled both brakes on my 2017 ABS using the "standard" procedure and both are "rock solid" (if I can use that expression...).

Unfortunately, I think the service manual does say you should pump the ABS reservoir - I'm guessing 90% of people skip this. This is tough to do without a diagnostic tool. There's probably not much that much bubble in the ABS system, but there may be some.

[navid]

13 hours ago, Triple Jim said:

With ABS brakes you need to run the pump when bleeding or you'll never get the air out.  Have you done that?

If I may ask, is there a hack to do this or do you need an expensive diagnostic tool? I can engage ABS by riding rough on dirt, but how do I guarantee that I move all the bubbles out of the ABS loop?

Edited May 21 by navid

[Triple Jim]

For the rear brake I'd find a gravel road or some wet grass and lock the wheel a few times.  Not to tell you to try that, of course.  

There's a recent thread here with a description of a procedure a member used to do it in his garage.

Edited May 21 by Triple Jim

[navid]

7 minutes ago, Triple Jim said:

For the rear brake I'd find a gravel road or some wet grass and lock the wheel a few times.  Not to tell you to try that, of course.  

There's a recent thread here with a description of a procedure a member used to do it in his garage.

Thanks, that looks like the move. I'd rather not short my ABS connectors. I do suspect that my issue isn't the ABS bubbles. If my understanding is right, the ABS and regular system fluids only mix when ABS in engaged. I haven't engaged it since I bled.

Edited May 21 by navid

[Triple Jim]

3 minutes ago, navid said:

Thanks, that looks like the move. I'd rather not short my ABS connectors.

I found the video he made: 

 

Edited May 21 by Triple Jim

[clinical]

I just stumbled on this.  My 0.02 after helping a buddy bleed an ABS bike.  If you have have no air in your system, there's no problem just doing a bleed without activating the sensors.  But if you have a bike that's has a lot of air in the system (i.e. to the point you make this post, or ask your buddy to help you bleed the brakes), then you probably also have air in the ABS circuit as well that will require ABS actuation to bleed.

[AP996]

Replaced front and rear brake lines and front master cylinder on my abs equipped bike, so completely dry brakes, just bled in the normal way and no problems. I did make a point of activating the rear abs just by stamping on the lever on the first ride but didn’t notice any difference from doing that.

Just my experience with this.