Is there a trick to quiet the front discs?

[Dave334478]

So, the dual front discs are floating and it's normal for them to rattle when I hit a bump at low speeds but, I don't like it!

 

Has anyone tried to quiet them? 

 

I was wondering if some careful application of silicone adhesive in the gaps would eliminate the noise while still letting them float properly.
 

[Red]

Don't know exactly what your rattle is caused by.  I solved the rattle in my 96RT by replacing the bobbins.  

[wbw6cos]

Fishing line?   Use a line that fits and add some automotive goop and wrap it tight around the rivets.

[dirtrider]

6 hours ago, Dave334478 said:

So, the dual front discs are floating and it's normal for them to rattle when I hit a bump at low speeds but, I don't like it!

 

Has anyone tried to quiet them? 

 

I was wondering if some careful application of silicone adhesive in the gaps would eliminate the noise while still letting them float properly.
 

Morning   Dave334478

 

Depends on the motorcycle make & model. 

 

I doubt anything like silicone adhesive would  last as (depending on how hard you brake & for how long) those front disks can normally run up to 500°f or more with the possibility of reaching close to 1000°f + under severe braking. 

 

You don't want to use anything that could/would prevent proper floating. 

 

Again, depending on the BMW motorcycle, if the rotors use replaceable bobbins then installing new bobbins can quiet the rattle significantly.  

[Selden]

8 hours ago, Dave334478 said:

 

Has anyone tried to quiet them? 

 

Measure your rotors with a micrometer. If they are at or near minimum thickness, replace rotors and bobbins in one step. At ~110,000 miles the rotors on my 1999 RT were at minimum thickness spec, so I replaced rotors and bobbins. Noise gone.

 

With a heat gun to soften the Loctite, the job took less than an hour, one of the easiest maintenance tasks I performed in the 65,000 miles I owned the bike.

[Michaelr11]

I've used replacement bobbins from Cata Dan.  Very reasonable cost, nicely made.  Like Selden says, one of the easier maintenance tasks.

 

https://boxer-upgrades.webs.com/apps/webstore/products/show/3821625

 

[Bodag]

Replace the bobbins, problem solved.

[AndyS]

I'm with Bodag on this. 

Replacement bobbins are available from a variety of sources.

 34 11 2 310 086

https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51680&rnd=09082020   fiche 34_0660 items 2,3 and 4.

 

Also visit Motorworks:

https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=6&Q=+34+11+2+310+086&search=SEARCH  item BRA10086

 

Also visit Dan Cata: https://boxer-upgrades.webs.com/apps/webstore/products/show/3821625

[Bodag]

8 hours ago, AndyS said:

I'm with Bodag on this. 

Replacement bobbins are available from a variety of sources.

 34 11 2 310 086

https://shop.maxbmw.com/fiche/DiagramsMain.aspx?vid=51680&rnd=09082020   fiche 34_0660 items 2,3 and 4.

 

Also visit Motorworks:

https://www.motorworks.co.uk/vlive/Shop/Parts.php?T=6&Q=+34+11+2+310+086&search=SEARCH  item BRA10086

 

Also visit Dan Cata: https://boxer-upgrades.webs.com/apps/webstore/products/show/3821625

 

I got mine from Cata Dan, Excellent quality - at a very good price.

[Dave334478]

I'm confused now.

 

MAX BMW shows 9 regular bobbins and 3 bobbins with snap rings per disk.

 

Dan Cata shows 12 regular bobbins per disk. (Made from aluminum, which makes sense the way He explains it)

 

Motorworks show 12 regular bobbins  per disk. (Made from stainless steel) 

 

The picture in my OP is just one I grabbed off the web. On my bike I can clearly see that every 4th bobbin is different from the others. (per disk)

 

It's obvious the bobbins are wear items so they should be made of a softer material then the disk or disk mount. The disk may be harder then stainless steel but I doubt very much the disk mount is and MAX BMW does not specify what material the ones they sell are made from. 

 

Question 1 - Do I really need the 3 bobbins with snap rings or not? (per disk)

 

Question 2 - I should avoid the stainless steel ones yes?

 

 

[dirtrider]

Morning Dave

 

The picture in my OP is just one I grabbed off the web. On my bike I can clearly see that every 4th bobbin is different from the others. (per disk)-- 3 bobbins per disk have internal snap rings to cushion & center some of the rotor rotational movement so they don't rattle. (not absolutely needed but they do help prevent rotor rattle for a longer time frame)

 

It's obvious the bobbins are wear items so they should be made of a softer material then the disk or disk mount. The disk may be harder then stainless steel but I doubt very much the disk mount is and MAX BMW does not specify what material the ones they sell are made from. -- They need to be softer than the rotor or the carrier so all pieces don't wear out (just the softer bobbins wear). Anodized aluminum alloy is usually a good choice, or at least a better, choice.

 

Question 1 - Do I really need the 3 bobbins with snap rings or not? (per disk)-- Needed?=No, but they are still a good idea as they prevent rotor rattling for a longer mileage or time.

 

You can install Dan's kit (no internal ring bobbins) then if they still rattle install the BMW 3 snap ring bobbins on each side to help quiet them down. (depends on how loose they are after Dan's kit install. Personally a little rattle never bothered me as that way I know they are free & working correctly. 

 

If you go with the 3 (snap ring containing) bobbins per rotor you REALLY should  rotate the snap ring bobbins one hole from where they are now. They live longer & stay quieter longer that way, but the big gain is at next removal, if you install the snap ring bobbins in the same hole they will be a REAL PAIN to remove next time due to the ring sticking in the worn hole.   

 

Question 2 - I should avoid the stainless steel ones yes?-- Yes, if possible.

 

 

[Dave P]

Don't think you ever mentioned what bike you are on. My 1100 RT I think had 12 bobbins (that I replaced with a Dan Cata kit). I bet the 1150s, since they have different wheels used a different kit. Anyway, my 1100 had 12. Also, I painted them black so they would blend in a little better. Dave

[dirtrider]

4 hours ago, Dave P said:

Don't think you ever mentioned what bike you are on. My 1100 RT I think had 12 bobbins (that I replaced with a Dan Cata kit). I bet the 1150s, since they have different wheels used a different kit. Anyway, my 1100 had 12. Also, I painted them black so they would blend in a little better. Dave

Afternoon Dave

 

Once he mentioned  "9 regular bobbins and 3 bobbins with snap rings" that pretty well tells us what motorcycle he is working on.

 

The 1150 free floats the entire one piece rotor on 5 spools (roll pins) so uses a one piece rotor not the 2 piece rotor with bobbins that the 1100 uses.

 

 

[Dave334478]

Thanks Dirtrider, that covers everything. 

 

I only ride it occasionally and never very far so I'll just go with the kit Dan Cata sells to start.

 

All noises bother me! I'm still getting used to being able to hear the injectors.

 

6 hours ago, Dave P said:

Don't think you ever mentioned what bike you are on. My 1100 RT I think had 12 bobbins (that I replaced with a Dan Cata kit). I bet the 1150s, since they have different wheels used a different kit. Anyway, my 1100 had 12. Also, I painted them black so they would blend in a little better. Dave

 

I only have the one bike that is my profile picture but yeah, I should be more specific in my posts so, I made created a signature specifying what bike I have.

[AndyS]

16 hours ago, Dave334478 said:

I only have the one bike that is my profile picture but yeah, I should be more specific in my posts so, I made created a signature specifying what bike I have.

So Dave, it still isn't clear what bike you have.  Your profile picture infers it is NOT and RT.

[Dave334478]

2 hours ago, AndyS said:

So Dave, it still isn't clear what bike you have.  Your profile picture infers it is NOT and RT.

 

Do you have signatures turned off?  My signature now reads "1997 BMW R1100R ABS ". I see it at the bottom of every post I've made now. Many others have similar ones.

 

 

[Dave334478]

So, update. 

 

The parts arrived from the other side of the planet. (I got them from Dan Cata)

 

I just finished one side with nothing but a screwdriver. No need to take the wheel off. I just did them one at a time in a cross pattern. I'll do the other side tomorrow and then post again after I take it for a test drive.

 

Left side, before...                                                                                       ... and Right side after.                                                                     

 

 

  

[Dave334478]

So, armed with only an extra long flathead screwdriver (I stuck it through the holes in one side for leverage to push the new c-clips on, on the other side) it took about an hour total and I can't hear the front disks rattling when I ride over bumps any more ;)

[King Herald]

The discs are not a floating design, the callipers are twin opposing piston, that deals with pad wear without the disc having to move. The bobbins are there purely to allow thermal expansion.

Mine were pretty tight from corrosion when I bought my '97 1100r and so I loosened them up, by sticking a nut and bolt in and rotating with a battery drill a few revolutions, after seeing a mechanic in a bike shop doing it to some Japanese race replica....

Next time I rode it they were rattling all over the place.  

 

So, I replaced them all with neat little stainless steel ones bought from Motorworks in the UK and all is well now.

[dirtrider]

1 hour ago, King Herald said:

The discs are not a floating design, the calipers are twin opposing piston, that deals with pad wear without the disc having to move. The bobbins are there purely to allow thermal expansion.
 

Morning King Herald

 

That doesn't agree with most motorcycle brake rotor suppliers as most if not all call call their  brake rotors, the ones that have a fixed center (spider) with the outer braking ring attached by rivets or bobbins,  FLOATING rotors.  

 

Technically they are probably more of a semi-floating rotor but most just call them floating without using the "semi"  or "full". 

[King Herald]

23 hours ago, dirtrider said:

Morning King Herald

 

That doesn't agree with most motorcycle brake rotor suppliers as most if not all call call their  brake rotors, the ones that have a fixed center (spider) with the outer braking ring attached by rivets or bobbins,  FLOATING rotors.  

 

Technically they are probably more of a semi-floating rotor but most just call them floating without using the "semi"  or "full". 

 

I've always considered a 'floating' rotor as being designed to allow the disc to move sideways to accommodate brake pad wear. You can physically shove it a 1/16" to the side with ease. There is no actual movement on the BMW, zero sideways clearance.  Maybe semi floating is the correct term.

[Dave334478]

I've put about 20 mi on the bike since installing all new bobbins in the front. Though they make much less noise now, the front rotors are still "floating".

 

PS: Can someone explain to me how to control the actual display size of the video?

 

 

 

[King Herald]

Mine rattled like before I changed them. After I'd fitted new bobbins there was zero movement. Theres always a chance your bobbins have been manufactured undersize, as I very much doubt the holes stainless disc/centre have worn.