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Brake rotor pulsing - resolved

Re: brake rotor ?

Art
The rivets were struck from the rear because it was the peening over the spring washers which needed to be eased. The club hammer was used because more accurate force can be applied with a heavy hammer, not to apply a lot of force. The rivets were loosened just enough that they could be rotated between a thumb and forfinger.

Robert's advice is spot on. Brakes need regular excercise for good health, and it's the best way to clear a rotor of pad-material contamination.
 
Re: brake rotor ?

There is an even easier solution - I made up a mandrill from a bolt - straight through the bobbin and put the free end in a reversible drill. Rotate the heck out of each one for 10 seconds, then move onto the next one. Once freed in this manner, bad vibes gone altogether (once the buildup from the pads was worn off). Bike now up to 24,000km and still vibe free braking! You don't even have to take the wheel off!
 
Re: brake rotor ?

Oz1200Guzzi

Clever system.

Did you rotate the bolt/mandrel anti-clockwise so that there was a tendency for bolt-head pressure to pull on the rivet inner end?

After the operation were there witness marks or swarf evident?
 
Re: brake rotor ?

Some swarf but mostly dirt. Quick blast with compressed air will clean it all up. Sometimes the bobbins can be heard shaking/rattling if the disk is in the right position when idling - at least I know they are not too tight!
 
Re: brake rotor ?

Oz1200Guzzi said:
There is an even easier solution - I made up a mandrill from a bolt - straight through the bobbin and put the free end in a reversible drill. Rotate the heck out of each one for 10 seconds, then move onto the next one. Once freed in this manner, bad vibes gone altogether (once the buildup from the pads was worn off). Bike now up to 24,000km and still vibe free braking! You don't even have to take the wheel off!
Click to expand...

Now this sounds like my sort of fix.. my bobbins have very little movement at the moment even after a little persuasion. The description of the boddins rattling at idle tells me just how loose to aim for.

Just so I know exactly what works am I guessing right that the bolt needs to be just a little smaller in diameter than the bobbin hole so that when reverse rotating it vibrates agaist the sides and you also allow the bolt head to rotate against the backside fasteners ?

Art
B11
 
Re: brake rotor ?

The general idea of this method of loosening the rivets is interesting and appealing, but we need more detail.

Is the bolt fitted with a nut tightened about the rivet?
Must rotation be anti-clockwise?
Where is the wear occuring to produce the loosening?
 
Re: brake rotor ?

Yes, sorry guys, use a nut done up tight and drill the opposite way to the thread so it does not undo. You get the picture...

So easy and takes about twenty minutes for both sides of the front wheel - then GO FOR A RIDE
 
Re: brake rotor ?

Assuming a R/H thread, insert bolt from the inside out, tighten nut lightly, attach drill and (I think ) drill anti-clockwise. Undo and repeat till cooked.
 
Re: brake rotor ?

Not my idea - read it on the 1200sport.com forum - I think. I guess I am a tightarse mechanic and look for tools that are in the toolbox or the spares bucket (nuts, bolts, washers even BSF and BSW - harking back to the BSA days) and not to be specially manufactured
 
Re: brake rotor ?

Oz1200Guzzi

Modest too!

There are BSF and Cycle thread fasteners in my antique section.............

My loosening method does use common workshop items and is aimed at attacking the primary reason for the rivet tighness - the head peening being too severe. But I like "your" method better because it appeals to my lazy side!

There is a saying that "lazy men take most pains", and while that can be true, there's another saying that "a challenging task is best allocated to the laziest member of the team, because he'll find the easiest way to do it."
 
Re: brake rotor ?

After having had trouble with pulsating brakes for a while, my workshop dialed the discs. Right hand was 0,2 mm (cirka 0,008") and the left one was 0,7 mm (cirka 0,028").

What's the service limit?
 
Re: brake rotor ?

The service limit is indicated/stamped on the disks themselves.
 
Re: brake rotor ?

Thanks GT-Rx but I was a bit unclear.
I meant limit for warp, not minimum thickness.
 
Re: brake rotor ?

Oz1200Guzzi said:
Not my idea - read it on the 1200sport.com forum - I think. I guess I am a tightarse mechanic and look for tools that are in the toolbox or the spares bucket (nuts, bolts, washers even BSF and BSW - harking back to the BSA days) and not to be specially manufactured
Click to expand...


I'd love to see a photo of this setup....
but failing that, I think I will give it a go!

thanks for the tip!
 
Re: brake rotor ?

No more warped rotors, I found these and bolted the ABS disk on.
 

Attachments

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Re: brake rotor ?

Matteo said:
No more warped rotors, I found these and bolted the ABS disk on.
Click to expand...
those look cool!
what are they? where did you find them?
 
Re: brake rotor ?

They are on e-bay. Around $300.00 for the pair. Just line em up and drill holes in the ABS wheel to mount. I went with 3 panhead screws. They feel great and perform very well.
 
Re: brake rotor ?

Matteo said:
They are on e-bay. Around $300.00 for the pair. Just line em up and drill holes in the ABS wheel to mount. I went with 3 panhead screws. They feel great and perform very well.
Click to expand...

ah

Item number: 150475835290

very cool

thanks
 
Re: brake rotor ?

I am not a fan of stainless rotors, but the price is not bad.
Especially if they really are made in the USA and not China.
Are you using the stock Guzzi pads with them?
 
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