Brakes? We don't need no steekin' brakes...

[Gregori]

Well, on my evening commute, I heard a strange 'scraping' sound as I was passing a truck, but after I passed him, the noise faded - so I attributed it to the truck.

 

Several miles down the road, when I exited at my ramp, the ABS lights started flashing. Uh-oh!

 

So I stopped, and went around back of the bike, expecting to find my taillight had come loose (as has apparently happened to others) and thus set the ABS alert off.

 

Rather than finding the light hanging loose, however, I discovered the ENTIRE REAR CALIPER hanging by the hose & ABS wire! (At least, I HOPE it's the entire caliper.)

 

Haven't had time to assess the damage - I just rolled into the driveway a few minutes ago. I pulled off the sidebags and hosed everything down with brake cleaner.

 

At the very least, I'm missing the 2 bolts that hold it on. Anyone care to guess what else is likely to be gone?

I'm hoping I can get parts, maybe I can button it up this weekend? I'll have to borrow a ministan, methinks...

 

Resignedly,

Greg

[No_Twilight]

Greg,

Ace hardware is still open. Go down and pick up a couple of bolts and ride it to work tomorrow. On my bike they are M10 by something short and get torqued to 40 NM. They aren't anything exotic and the bolts in the hardware store should be fine. --Jerry

[cjmkerns]

Greg,

 

If you are a pilot, as your avitar may indicate, you know a thorough walkaround (pre-flight) should be done before each flight. (can't afford to have an elevator fall off on us) As motorcyclists I think a thorough walkaround should be at least a weekly chore (check everything that moves or is critical). If you have your bike serviced by someone else, a walkaround should be done before riding away. But in any case I would examine why a caliper came completely off without being noticed.

 

And please, let us know what you find. Your experience and willingness to share it could save someone in the group a lot of pain. Maybe me.

[No_Twilight]

I don't know what Greg will find but there is only one possible (without very wierd things happening) explanation for the caliper coming loose--it wasn't torqued properly. I didn't ask who torqued it or when it was last checked. Greg will share that if he wishes. As for the "walkaround" loose bolts still sit in place and the loose caliper would not be obvious either unless you were moving and could see it wiggling. --Jerry

[cjmkerns]

Jerry,

 

On a pre-flight you don't just look, you "wiggle" everything.

 

Regards,

 

Carl

[No_Twilight]

Ok. I'll admit I've never done a preflight. I always keep at least one wheel on the ground...--Jerry

[russell_bynum]

On a pre-flight you don't just look, you "wiggle" everything.

 

I used to hang out at the local small airfield as a kid, washing planes and basically doing whatever I could to bum rides. One particular salty old guy had a 172 and part of his preflight was to grab each wing at the tip and shake the airplane. One day I asked what he was doing. "Making sure the wing isn't loose."

 

As he walked back along the fuselage, running his hands along a line of rivets I asked "Ever find one that's loose?" He didn't say anything for a while. He just kept going back, checked the horizontal and vertical stabilizers and the rudder and elevator. He walked foreward up the other side of the fuselage, again feeling the line of rivets, checked the baggage door, wiggled the flaps, moved the ailerons through their full range of motion, then went out to the wingtip and shook it vigorously.

 

Then he looked at me, smiled and said "Not yet."

 

We have lots to learn from old pilots.

[Gregori]

Jerry - Ace hardware? Nice idea - in a pinch (no pun intended, of course) that would work great. But while the hardware store may have a bolt that fits, I'd prefer to put the RIGHT bolt on. (And the left one as well.)

 

Unfortunately, since there was brake fluid all over, and the ABS lights went nuts, the system clearly needs fluid and a bleed. I expect it'll take more than simply bolting the caliper back on to set it straight.

In fact, I'm *even* giving consideration to getting it to the dealer, just for expediency.

 

That said, it's clearly the idiot who last serviced the bike who is to blame, and I am certain he'll pay dearly for this error. For that idiot is I. (And I *did* have the rear caliper off at the Tech Daze here last August.)

 

Carl - I'm no pilot (though I *am* the Indiana Jones looking guy in the jet - a long story best told over a glass of wine...)

I do, however, 'preflight' the bike at least weekly. (Usually twice a week, or before any 'real' riding.) While I don't grab and shake every bolt on the bike, I do the obvious fluid and tire checks, look for leaks, make sure the BIG stuff isn't loose, ensure the lights operate, and that the controls do what they're supposed to. But in a recent thread someone else nearly lost the final rive (or torque arm?) while riding - so maybe I (we?) SHOULD take a look at all the bolts more often than semi-annually.

 

In any case - I took some pics, and will upload them later...

 

Grins,

Greg

[russell_bynum]

If you've also dumped brake fluid, that's a problem.

 

I'd guess you either damaged a brake line, or maybe you ejected a piston out of the caliper. I can't see how else you'd be dumping brake fluid.

[Gregori]

Oh yeah, it's dumped fluid. Ejected piston, I think, though it appears to NOT have been lost. But the system is unquestionably open.

 

Dang - I just filled up yesterday, so that tank is gonna be HEAVY.

 

G

[russell_bynum]

Are the pads still there?

[KMG_365]

That said, it's clearly the idiot who last serviced the bike who is to blame, and I am certain he'll pay dearly for this error. For that idiot is I. (And I *did* have the rear caliper off at the Tech Daze here last August.)

Damn, Greg!!!

 

Didn't we do your bike the second day--just the two of us? I feel sick about this.

 

As a novice wrench myself (and slowly losing my powers of concentration) I ALWAYS try to double--even triple check my work before moving on--when I'm working on my bike or when I'm assisting others. Was I still there when you were buttoning things up at the end of the day? The only other thing I can think of is if there was some grease on the bolts. You've put some hard miles on that bike since August, but I guess if they were just tightened, but not torqued down ALL the way, it might've taken this abount of time to work themselves all the way out. I always worry about putting bolts back in "for now" or "temporarily" for fear that I'll forget to do a final, proper torque and in just looking think I was finished. The front axle pinch-bolts are like that in that you torque the one side and then compress the suspension a few times before torquing the other side. I'm always so paranoid that I'd rather check them again than risk having my front wheel come off in a fast sweeper in the middle of nowhere.

 

I know it can be distracting at a tech daze (especially one where you're the host) where everyone is talking, eating, laughing and having a good time while wrenching. I'm sure sorry if I played any part in your mishap and you can come by and get the Mini-Stan any time you want, of course.

 

Glad you're okay and there were no other (non-monetary) consequences. If the local dealers don't have the parts you need in stock, give Mike at www.beemerboneyard.com a call and if he's got some used ones, he can sometimes overnight the parts you need (and you'll save a bundle buying used). I've had VERY good luck dealing with him and he's a heck of a nice guy.

 

As far as just the bolts go, I would be VERY leery of just putting any old bolt in there. Metric are hard enough to find, but those with the proper hardness are even harder (to find ). You might be able to find them at Marshall's Hardware up off of Miramar Rd. (about midway between the 805 and the I-15). They might even have the proper Torx headed bolt--it's amazing the stuff they stock for cheap! They've got Metric, SS, all kids of stuff and you can buy just ONE screw or nut or washer if that's all you need!

 

Best of Luck!

[Gregori]

Russell - the pads ARE still there - but there is a through bolt, IIRC? (On looking at pix - yes.) They're not in 'position,' but are hanging from the caliper.

I think the tensioner springs (or whatever they're called) are laying out on Hwy 52, however...

 

Jamie - we did torque them down - front and rear. Obviously, the torque value (or the wrench) is inadequate. It's either that, or the guy running the wrench is! (I'd much rather blame the hardware than the hard-head...)

 

Should get pix up in a few minutes... My hardwood floor was installed this week, and we went out tonight to get a 'holiday fir' to decorate.

 

Grins,

Greg

 

(Edit - added pix.)

 

[lithoman]

Man your lucky the whole thing didnt go into your spokes!! and rip your brake line off if it was just dangling there

hope you get it fixed soon, let us know what you find , if anything!! from the pix, it's hard to tell

[No_Twilight]

Clean the brake fluid off the paint ASAP. Brake fluid eats paint. If you can get the piston back in w/o damaging the seals and clean everything up, you should be ok. I think you'll want new pads that aren't soaked in brake fluid. Before I took it to a dealer I'd just pick up a new caliper from beemerboneyard. Used ones are relatively cheap because they don't fail often on BMWs because people change the fluid. Good luck, Jerry