FJowners.com

General Category => Yamaha FJ1100 / FJ1200 Running Problems => Topic started by: Zwartie on April 03, 2015, 06:50:33 PM

Title: Hot Hot Hot! - caliper, that is
Post by: Zwartie on April 03, 2015, 06:50:33 PM
Sooo, after spending a good part of the day reassembling my '92 FJ (new rear sub-frame) I decided to take her out for a little spin. I checked to make sure the front and rear brakes were functioning by doing a little ride up and down the street and had also tested the rear brake after installing the rear sub-frame by making sure the rear wheel spun freely and then of course didn't when I applied the brake. No noticeable issues when I walked the bike or rode at slow speeds. I got onto a secondary road and did sense that the bike seemed to be hesitating a bit which I thought was odd  - it felt a little flat at the mid-range but I figured she just wanted to be opened up at highway speed to clean things out. So I hit the 401 (expressway) for a km and then rode for another 5 minutes or so and it felt better...and then I suddenly lost the rear brake - completely. Pulled over to check things out and this is what I found:

(http://fjowners.com/gallery/8/112_03_04_15_5_31_18.jpeg)

After taking the picture I was able to put the fire out which I believe was fueled mostly by the plastic caps at the top of the caliper assembly. I waited for a bit and rode gingerly all the way home and she's now parked in the garage. Next steps - find out what cause the rear brake to stick and then get a replacement rotor, pads, and likely a new caliper or possibly a rebuild.

Sigh...
Title: Re: Hot Hot Hot! - caliper, that is
Post by: X-Ray on April 03, 2015, 07:01:27 PM
Wow, there sure was some heat generated there. I don't see how replacing the subframe should have affected the rear caliper though?
Title: Re: Hot Hot Hot! - caliper, that is
Post by: FJmonkey on April 03, 2015, 07:02:40 PM
Smoking... (http://giphy.com/gifs/641arBi22PAty/html5)

Title: Re: Hot Hot Hot! - caliper, that is
Post by: Pat Conlon on April 03, 2015, 07:37:04 PM
Yep, a stuck piston will do that....

Ben, I have a low mileage rear caliper off my old '92 you can have if you want it.....PM me your address and I'll get her in the mail.

I had a brake arm come apart (broken weld) and that was exciting......your mobile bbq is much more dramatic.
Title: Re: Hot Hot Hot! - caliper, that is
Post by: fj johnnie on April 03, 2015, 08:30:13 PM
 You have an FZR wheel on your bike yes? Is the caliper the same as the FJ? If so I have a spare as well.
Title: Re: Hot Hot Hot! - caliper, that is
Post by: Zwartie on April 03, 2015, 09:45:32 PM
Here's a picture of the brake pads - something tells me they are not to be salvaged.
(http://fjowners.com/gallery/8/112_03_04_15_8_38_33.jpeg)

View of the Rear Caliper from the wheel side
(http://fjowners.com/gallery/8/112_03_04_15_8_37_58.jpeg)

Rear Caliper from the outer side
(http://fjowners.com/gallery/8/112_03_04_15_8_37_18.jpeg)

By comparing it to photos of FZR and late-model FJ rear calipers I'm thinking they may be one in the same. Pat, Johnnie, does it look similar to yours?

Thanks for your support! Again, this site and more importantly its members are proving invaluable!

Zwartie
Title: Re: Hot Hot Hot! - caliper, that is
Post by: yamaha fj rider on April 04, 2015, 06:15:27 PM
Quote from: FJmonkey on April 03, 2015, 07:02:40 PM
Smoking... (http://giphy.com/gifs/641arBi22PAty/html5)


I thought it would be something more like this.
(http://www.24-timepass.com/postimg/monkey-skill/smoking.jpg)

Kurt
Title: Re: Hot Hot Hot! - caliper, that is
Post by: Zwartie on April 06, 2015, 08:45:33 PM
Thanks John and Pat for your offers. My good friend (and colleague) Rob Hersey came through with a spare caliper off of his former FJ1100 - before the 17" wheel upgrade.

Looks like a perfect fit and it says "Yamaha" on the side so you know it's full of goodness!
(http://fjowners.com/gallery/8/112_06_04_15_7_36_08.jpeg)

Thanks Rob!

Next steps, cleaning and inspecting the rotor and replacing if necessary, installing braided brake line and charging it up again!

Zwartie
Title: Re: Hot Hot Hot! - caliper, that is
Post by: FJmonkey on April 06, 2015, 08:52:01 PM
Now try to keep the smoking to the tires...
Title: Re: Hot Hot Hot! - caliper, that is
Post by: yamaha fj rider on April 06, 2015, 09:02:34 PM
Quote from: Zwartie on April 06, 2015, 08:45:33 PM
Thanks John and Pat for your offers. My good friend (and colleague) Rob Hersey came through with a spare caliper off of his former FJ1100 - before the 17" wheel upgrade.

Looks like a perfect fit and it says "Yamaha" on the side so you know it's full of goodness!
(http://fjowners.com/gallery/8/112_06_04_15_7_36_08.jpeg)

Thanks Rob!

Next steps, cleaning and inspecting the rotor and replacing if necessary, installing braided brake line and charging it up again!

Zwartie
Looks good, glad it was not worse. With the Yamaha on the caliper, it's an upgrade.

Kurt
Title: Re: Hot Hot Hot! - caliper, that is
Post by: Zwartie on April 24, 2015, 09:25:02 PM
Update: I took the "crippled" FJ to East London Motorsports, one of the local shops to check out the rear brake and install a new caliper along with anything else in need of replacement. While they were at it I had them flush/bleed the front brake and clutch. Went with a new wave rotor and braided lines for the rear. They also checked out the rear brake linkage and determined that the brake malfunctioned when the master cylinder piston got jammed. Due to this particular bike having the much wider FZR1000 swing arm there's not enough room for the master cylinder assembly to be in the normal location. It was moved (by the first owner) to a location on the rear sub-frame with a bit of an elaborate linkage between the rear brake pedal and the master. Turns out that when I installed the new-to-me rear sub-frame I may not have aligned the master cylinder assembly and linkage as well as I should have (expensive lesson!). They have since tweaked things so the alignment is better and it won't stick anymore. Unfortunately the rear caliper with the Yamaha logo that Rob Hersey gave me had a seized piston so I took FJ Johnnie up on his offer - thanks to both of you guys and this forum as a community of support!

So here's the new assembly with the gold caliper, wave rotor and braided lines.
(http://fjowners.com/gallery/8/112_24_04_15_7_59_49.jpeg)

(http://fjowners.com/gallery/8/112_24_04_15_8_03_28.jpeg)  (http://fjowners.com/gallery/8/112_24_04_15_8_02_23.png)

Thanks again!

Zwartie
Title: Re: Hot Hot Hot! - caliper, that is
Post by: fj johnnie on April 24, 2015, 10:27:53 PM
 It sure looks good now!
Title: Re: Hot Hot Hot! - caliper, that is
Post by: FJmonkey on April 24, 2015, 10:29:40 PM
I think you need a bit more GOLD!!!