front brake issue

[weaselnoze]

#7 here  is rubbing the rotor.  its flush with the pad.  WHY?!  is the pad too thin?

[werase643]

you installed it wrong......

obviously you got the brgs in

[weaselnoze]

yes i did get them in.  thanks to everyone who posted.  so am i really installing the pads wrong or something?

[werase643]

i'd go with the or something

[werase643]

why did you rip the caliper apart....while changing the wheel

[weaselnoze]

it fell apart when i put the wheel back on.  well the metal clip came off a little.  i dont see its purpose.  i removed it all together and now the thing it sits on hits the rotor.  i've thought about it and dont even see how the pad thickness would make a difference.  im so fed up with this i quit.

[Kerry]

You didn't say whether you thought you got it back on right.  

Here is my '99 unit from the (right) side:




And here it is from the front, with its reflection in the rotor:



Sorry about that second shot - it was lit only by my PrincetonTec Pulsar:


PS - Next time try a diagram from the MrCycles fiche.  Not only do they have lower prices, but their drawings are more sharp.  

[raylarrabee]

Sorry about that second shot - it was lit only by my PrincetonTec Pulsar:

Kerry, did you learn about that on the "Flashlight Enthusiast" forum you claimed to have stumbled upon?  

[Kerry]

Heh heh.  Good one!  

Naw, it came packaged in with the Aurora headlamp that I take on long trips:



But now that you mention it, maybe I am a junky.  I carry a 2-AA MagLite in my jacket at all times....  

Say, has anyone made a mini-MagLite holster out of Kydex?  Can I get your pattern?  :mrgreen:

[Kerry]

Hey weasel!  Did you ever figure this one out?  I remember that you started another thread about it ( :x ) but I can't remember whether you ever arrived at a solution.

Anyway, I'm writing to report that I had the same problem over the weekend, and that I found out WHY last night.  It had nothing to do with the caliper itself!  Here's a hint: I'm going to remove the following picture from the HOW TO: Front Rotor Replacement thread in the FAQ forum.

Read on....



About a week ago I noticed three things on my bike:

• Both of the front fork tubes were "yucky" with oil and road grit.
• The "yucky-ness" extended to the surrounding area: fork brace, fender, etc
• There was a visible "drip" of dark liquid where the front brake hose meets the banjo bolt.

In other words, my fork seals were blown and fork oil had been dripping onto my front rotor! No WONDER I had noticed a marked decrease in front brake performance lately. So I removed the forks, took them apart, replaced the seals, cleaned everything, etc. etc.

The point here is that I HAD to slacken the right fork pinch bolt like in the photo above, because I HAD to remove the axle spacer trapped in the fork, because I HAD to get to the fork damper bolt so I could take the fork apart.

OK ... fast forward to reassembly time.  I don't remember the exact sequence I followed, but the spacer was put back in and the pinch bolt tightened without thinking about the spacer's exact position.  MISTAKE! When I started the bike up and rode it from the shed in my back yard out to the driveway, I heard (and felt through the handlebars) a loud "TAT TAT TAT TAT" that varied with my speed.  I immediately thought about this thread.  It was after dark though, so I put off diagnosis until last night.

It turned out that the "guide" (see pictures at the top of the thread) was rubbing on the front rotor and then catching on the drilled holes as they came around. ("TAT!")  I took the caliper off at least 3 times, trying to figure out what had changed.  Every time I put it back on and spun the wheel: "TAT TAT TAT!" :x

Finally ... finally ... I turned my attention to the forks themselves.  I wondered whether they were too close together somehow, and pinching the "guide" against the rotor.  It took me long enough, but I finally looked at the axle spacer in the photo above ... and realized that it was sticking out farther than I remembered it doing in the past.  That's when the light came on.

The positioning of that spacer is critical, because it helps determine the distance between the forks.  If you look at the parts diagrams and think it through, you will see that the right fork is not directly involved in the axle-tightening sequence like the left fork is.  The final position of the right fork is dictated by the position at which the "trapped spacer" is clamped into it.

In the end I:

• Loosened the pinch bolt
• Did what I could to pull the right fork a little farther from the wheel (or to get the spacer to move farther into the fork)
• Retightened the pinch bolt.

I only moved things about a millimeter, but that was enough.  Now the wheel spins with no "TAT TAT TAT!" - only the regular "whisssshhhhh" of the pads slightly contacting the rotor.

MOTTO: Don't move / remove that spacer unless you have to!  Certainly not for standard wheel removal.  If you DO need to (re)move the spacer, mark its position and make sure you get it back in the same place before tightening everything back down again.

[Cal Price]

I  carry a 2 x AA Mag at all times, and I have one of those headlight thingys, and a single cell led on my keyring, spooky or what??

Flashlight / Torch junky that I am I have just bought one of those wind-up flashlight gismos that I don't really need.

[weaselnoze]

kerry, no i didnt ever get teh problem fixed completely.  when the bars are turned far left or far right i get teh tat tat rotor sound.  i figured it was beyond my abilities so i threw the whole bike in the garage and havent touched it since.  in fact i rarely come here anymore too.  i just cant deal with the stress i guess.  i have a new throttle cable ordered; should be here in a few days, then i'll take a look at this guide thing.  thanks for keeping me in mind!

[purplepeopleeater]

It's took me ages to find this post after i replaced my front wheel and found the caliper rubbing on the rotor.
I eventually found this and will yet again spend all day today probably causing more problems than ever.

"In the end I:
•Loosened the pinch bolt
•Did what I could to pull the right fork a little farther from the wheel (or to get the spacer to move farther into the fork)
•Retightened the pinch bolt."

Not tried this yet but i can't understand that there will be freeplay at the fork and spacer, or does the pinch bolt determine the width of space between the forks?
Cheers

[the mole]

The whole axle assembly tightens up to the left fork, the spacer pinch bolt should be loose when you put it all together, then bounce the forks up and down and make sure the fork legs are parallel. Last. tighten the pinch bolt.
If you tighten the pinch bolt first, then the axle nut you will likely pull the fork legs together at the bottom. This will cause brake problems and binding and undue wear of the fork sliders.