1200 DVT Dealer Wont Offer Solution To Pad Or -disc Issue = Vibrations Under Braking

I always use the brake lever, but use the cable tie method to stop the pistons coming all the way out. That said, it's not that bad to have them right out and give it all a proper clean. They pop back in easily enough.

 

I used a bolt and drill but as I didn't want to damage the wheels or tyres at all, I used Cillit Bang instead of brake cleaner. I didn't bother with washers and didn't damage the bobbins at all. I too used kitchen towel and lots of it because I kept going on each one until no more muck came out. There was a lot of muck...
It made a huge difference. The brakes are both much more progressive and much more powerful now.

 

Yup ask any middle aged woman.

As a matter of coarse I'd give the whole system a service from cleaning the callipers and bobbins to flushing the old fluid out with new stuff. also check your brake line where it runs down the fork leg for wear, I saw one a few months ago with a big shiny inner fork leg and the wire showing on the brake line.
+1 on the copper grease.

 

Copper slip and pads ?? I've read a few things on this from Brembo and Tmd friction and the likes ,and they recommend not to use copper slip .
If you have an aluminium caliper with a metal pad backing and use copper grease will this start off galvanic corrosion ?
They say to use a non metallic based grease like Ceratec , it does not start and diss similar metals reaction .
I see copper grease used all the time with car stuff , it seems to work but something to take note of for all the OCD squad

 

Don't spin the bobbins with a drill when you clean them .. there's no need for such speed and it just wears out the bobbin holes, or at the very least degrades the anodising so that corrosion sets in later.
Turning by hand is perfectly adequate.

Many supposed cases of "warped" discs are not warped at all .. its often down to the surface conditioning (sometimes called "tempering") of the discs.
Its a complicated subject but basically it is claimed that pad material is deposited in a micro-layer on the disc surface.
If this becomes degraded in one particular spot, or is not effectively carried out in the first place, pulsing is the result.
Often, the cure is simply to put them through repeated cycles of heavy use followed by cooling, to "condition" the surfaces.
I've had many mot advisories about my own front discs, which pulsed gently under light braking at slow speed.
Having cleaned the bobbins thoroughly and checked them for runout (none found) I cleaned the surfaces with scotchbrite followed by a light (and even) rub over with fine wet and dry paper on a small, flat block.
They still pulsed, although less so perhaps.
Then I noticed a slight improvement after a trackday when heavier than normal braking was the norm .. so I continued to use them more aggressively from time to time in my road riding.
The eventual result is that I have had no pulsing whatsoever for the last year or two.
Btw .. I have used the same pads throughout .. they're the originals (after 22k miles).
This possibly suggests the cause of the problem in that I tend to be a light, one finger only braker, relying much on engine braking on the roads and not using the brakes particularly aggressively.
I think I simply mollycoddled the discs too much and never properly conditioned their surfaces in the first place.
Anyway, they're fine now .. and the mot man agrees.

 

Fit fully floating bobbins,I've just done it on my 851 and the difference is amazing,it's went from about 4rpm with a gentle spin to 15-20 rpm with the same spin method! You'll not get any pulse as the disc moves to suit the pads!
I tried this on a old pair of discs I had stopped using because of a slight pulse,the experiment cost me about £55! I've now got less drag on the discs so more hp in theory ?

 

Fully floating bobbins are a good upgrade in my opinion .. but they shouldn't really be able to cure pulsation issues unless your original bobbins are sticking.
I've considered them myself though, but for other reasons.
Cheaper, stainless ones are available but Brembo make hard anodised, ally ones (with benefits to unsprung and rotating weight, so worth doing). I got mine from JHP, though you may need to order in advance (not forgetting the clips and shim washers too). I haven't fitted mine yet.
One good reason to go this way is that it would make it a bit easier to thoroughly clean/abrade the rotor surfaces (though it is perfectly feasible to do it without removing them).
Drilling out the old bobbins is tricky though (but then subsequently fitting the floaters is child's play).
I mention all this because I happen to know someone who is setting up to do exactly that, removing the rotors, honing them on a rotary table to restore the surface, and refitting to the carriers using fully floating bobbins.
Between us we strongly suspect that this will be a total cure for pulsing discs, as well as a performance upgrade.
Unfortunately it will be some months yet before the process will be up and running, but if you're not in a desperate hurry it might be a good solution.
Or, you could do it yourself, cleaning the discs up with wet and dry as I did (on the bike in my case).
Whichever way you go, I would recommend that you then put the refurbed discs (or new ones for that matter) through a conditioning/tempering process to ensure their continued smooth, pulse-free operation.

I suspect that a dealer is likely to quote "warped discs" and try to sell you a new pair.
In fairness, although the analysis may not be correct, its probably the easiest quick cure, so I can't criticise too much.

Oh, and the other issue with full floaters is that some mot testers don't like the way that they rattle and may be tempted to fail them on that .. although they probably shouldn't.
One way around this might be to keep a few of the old spring washers from the semi floating set up and fit them for mot time .. its easy enough and just requires removal of the circlip (assuming that the clearances are approximately the same on both types of bobbins .. you'd need to check that).

 

Riko, you need 100kms or more to get the pads properly bedded in before they will work at full capability, that bedding in period is longer if your discs are old/grooved/badly worn

 

You can't wear an offset into the disc? Well, only a fraction difference either side - but to be 3mm away from nominal offset there wouldn't be a disc left at all - or am I misunderstanding you

 

So it's warped 3mm! 'Lateral Run-out' is where the disc pads touch the disc face - the discs cannot be 3mm warped! Usually 0.1mm is normal. If you take your discs off and lay them on a flat plate with 3mm of warp you will see a minimum of 1.5mm gap under the disc in places. This would be unridable! The floating bobbins could be worn giving your 3mm reading as the disc itself would be 'tilted over' when measured - not warped. When you remove the disc try this and see what you find.
What did the other disc measure?
6 to 9mm on the edge of the disc - 'axial runout' - is also not possible - so very confusing.

Offset is how far the disc is away from the hub where it mounts and equates to the design of the system - to centralise the disc to the calliper centre.

 

How does 0.3mm suddenly become 3mm? This thread is nothing but mass confusion and conjecture