Floating Brake Discs - and bobbins
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- Опубліковано 15 жов 2024
- In this video we look at what floating brake components do, and the god horrible bullshit that has spread across the internet - that's right - rotating bobbins.
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I'd have never considered this because these are all that is holding the discs together. A guy at work told me I should do it while I was cleaning my calipers one day. I'm glad I came here first. This makes much more sense.
Very Good Explanation.
I might have missed you saying it, but another detail to point out is the center hub is typically a lightweight non-ferrous metal like aluminum, and the brake rotor is a ferrous metal for better strength, wear, ect. These two metals expand and contract different amounts when heated/cooled, and would be another reason to separate them with a button.
I first heard of cleaning bobbins when the discs of my new Monster began pulsing badly. Turned out it was warped discs. Then I had the same issue with another Ducati, then with a KTM. They all had one thing in common, Brembo brakes. I’ve rebuilt 4 sets of callipers because the pistons were sticky even though cleaned carefully every year. I’ve concluded that Brembos are maintenance heavy, they don’t like being left wet, or dirty. When they are working they perform brilliantly, but they don’t seem as reliable as Nissin.
My old boss miscalculated the expansion on the thickness when he developed some some floating discs on the rear brakes of cars we started manufacturing. The first test session we did at Donnington Park all 3 cars came back in with over half the bolt sheared off. The rest fell off when we touched them.
The discs in this video are typically referred to as semi-floating because of the spring washers. Race bikes often use full-floating discs which do not have the spring washers and I believe they have more clearance in the bobbins. Full floaters make a racket at low speeds. I believe the main reason for semi-floating discs is to make them quiet, and probably to make them last longer from them also having less rotational play.
I watched dellboys video on these bobbins years and years ago when I was starting out in biking. I have a bag of bolts in the garage which I specifically bought for his bobbins bs. However I'm lazy, thank fuck, so never actually did them. I've often wondered about them since, but any time I thought about taking a nut to them like he showed, my gut instinct just said 'no, if it don't seem broke'. This video has now settled it for me 😁. Thanks. My laziness, gut, and then your vids, also saved me from that evans stuff. I remember watching Dell's video on that too... I feel kinda stupid now thinking how impressionable I was/am, and how close I came to following his instructions, were it not for my laziness. Anyhow, I'd just like to say thanks again for your videos.
Just watched this as someone we know was cleaning his bobbins, this makes more sense than him. I thought it was for different materials used in the disk and hub assembly, but understand the expansion effect too now.
Going out to check mine now for movement.
Mattt.....I knew none of this (bobbins), you expained it very well.....Thanks
Just heard today that people mess around with their "bobbins" in the SVrider forum. Glad you had made a video about it already in your usual no holds barred style that I could post to counter the nonsense video there.
You had a fatal flaw in your diagrams, you didn’t draw the inch of copper slip you should paste onto the backs of your pads as described by EBC, come on Matt basics 🙄
AS DIRECTED BY EBC MATT !!!!!!!!!!!!!!!!!!!!
YEA!! this dripping off is what lubricates the bobbins. it's where scottoiler got the idea from
Fuck I was about to write the same thing!
When dellbs gets a floating disc hes gonna grease the bobbins
Diagram also misses chamfered brake pads, essential for optimal performance!!! :)
Another delbollocks distruction video, well done! Much appreciated. I can't believe I once watched that guy and thought he knew something.
So, you're sayin... Leave 'em alone??
All your vids are great bud. BUT! gotta point out something on this topic.
Everything you say is correct...OBVS...
But, rotating them sometimes isnt SO they rotate, but as a means for displacing brake dust and grit that can be holding the disc slightly out of alignment, (probably by filling in the recesses of some the bevel washers, so as the disc expands its pushed wonky??).
Now I have never had this on bikes ive owned for any length of time.
HOWEVER, I once bought an RSVR Haga rep off an old boy, and he rode it....gentle...
And he had replaced two sets of discs, because they kept 'warping'.
These were Brembos, so obviously designed for hard use.
Infact what it was, was because he never braked hard, the discs never expanded , but over the dry weather miles, dust built up in some of the bobbins, and eventually caused the disc to sit wonky.
And it got MUCH worse, when I bought the bike and actually put some heat in them. To the point that as you started applying hard brake from triple figures, the disc wobble would knock the pistons back in...NOT funny!
I rotated the bobbins, and got them turning (not because they need to turn, but to displace all the fine grit you could hear in there
Bam, they were like new. Wobble gone.
Also, after I did that I never needed to do it again, and I think it because I would use them enough to get them hot and use that expansion gap regularly so they couldnt get packed again.
If you go on the RSV forums, its a common problem with those brembos and steady owners.
Anyway great vid!
So my question to you is this. If just say like the Z900 the bobbins are solid when cold, there isn't enough room to for big bits of shit to get inside. But if were're talking dust then ok cool.
What you're talking about is people being pussies and like you said - after you got your hands on it then it never happened again.
On some brakes there is a lot of slop in there in the first place. But granted some 'special' people need to clean the shit out of their bobbins. The point that I'm trying to make is that it a very small amount of people who have to do it, because they should have a bicycle not a bike with an engine lol
This - as you said can also be down to shite discs etc.
Seen some of the same,.. My Brembos keeps building crud, and grime, then when going in wet weather.. Bhaam,.. Starts with a sick noise, and binding..
@@dirtygarageguy yeah, or shite in the disc holes,.. I put out a ton last autumn, grime lead to pads wear, noise and a shitty feel.. Neglecting service on the Brembos for years,.. Pads are different, roads are different..
WOW Matt massive respect at you I have seen videos form other youtubers rotating the bobbins but seeing the EBC oval bobbins proves beyond any doubt you do not need to rotate them. Great video ride safe bud thanks 😎
I didn't even know people were cleaning them...
Oh well, as long as it makes them happy
Learn something everyday.
People are cleaning them to try to stop brake squeal
So so so fucking glad you have done this video. I service some friends bikes from time to time and ALL of them must have seen the free your bobbins video as they always ask me to make sure i do it. I tell them its not how it works and try to explain what you have so eloquently put but its like im banging my head against a wall. Its that old adage, I seen it on the computer so it must be true 😂😂😂
I wonder how many people have warped their discs by sticking an impact gun on those so called stiff bobbins?
Excellent video Matt. I've been riding 30 years and never heard of this until recently. Think the internet has a lot to answer for!!!!
Old video but only just came across it. Agree with you that bobbins don’t need regular (or any maintenance), however, I recently worked on a vfr1200f with a binding front wheel. Callipers had been rebuilt, new pads, everything clean and moving nicely. Noticed unusual patterns on the front discs, like they were slightly warped. Never tried it before so thought I’d give cleaning the bobbins a go before replacing the discs. Plenty of salt/corrosion came out. Some started to move quite easily, others were really tight. Once all clean, none were loose, still a struggle to move by hand. Road tested and low and behold, binding cured and “warp” patent on disc no longer visible.
So while I agree with what you’re saying, I wonder if the bobbins could become tight to the point they no longer allow for even thermal expansion, causing your disc to warp slightly.
Then replace the disc...
Few hundred on new discs? Or half an hours labour? Think the customer preferred my solution....
@@rafaellozano8481 dgg is just wrong. Obvious build up of brake dust road grit could misalign moving parts. Slightly stuck off centre relative to the pad. Cleaned bobbins then binding puslating warped liked disc brake issue goes away. Must just be a coincidence .
The front rotors on my old Ducati 900SS jingle like crazy when pushing it about the garage, but work normally when under way. I've been told it is normal for the design (early floating design, 1995).
Great debunking vid Matt. That's one less job to put on the long finger!
Just for the hell of it, I dismantled my Ducati disc,s completely apart , all circlips away put them in an ultrasonic cleaner ( Bobbins ans clips) then used 3000 + grit and polished all Bobbins to a Mirror finish put them all back together and I still live and looks Awsom . I saw on your or an example that there where no circlips so dismantling is not possible.
I know this is a very old post, but thought I'd give my example. 20005 Triumph Rocket 3. One front rotor very hot after a ride, other side not. Replaced both calipers and pads, new wheel bearings, same thing. Cleaned my bobbins using a drill and simple green. Problem gone! Both sides stay same temp now. So, in my humble opinion. cleaning the bobbins DOES help
Well said Matt, I enjoyed the vid, way too many amateurs on UA-cam talking rubbish and putting people at risk.
Thanks dude. When I need to know something about how my bike works I come to you. Learning the theory helps so much more than the specifics. Although I should get a torque wrench, stripping my sump bolt collar was not fun. Keep up the good honest knowledge.
EEK.....I was led to believe the more the floating discs rattled the better they were. Something along the lines of room for the disc to self centre between pads for a better grip.
Will my off roader stop better in deep water if i fit floating calipers?
sure if the water is really hot
Get wave rotors, they expel water well. Galfer actually invented them for this particular purpose then they found that they work well on street/racing bikes
Nice one Matt, today I have learnt something.
I always thought it was for brake alignment too. Holy shit, you keep bashing down a lot of my wrong theories on bike engineering. Thank you, I think lol. Always great sir.
Wished I’d watch this video first. I might have saved myself about an hour of breathing brake cleaner fumes. I “cleaned” the bobbins based on forum advice as a solution for slow speed brake pulsing.
Great video, thanks Matt. I'll never mess with those bobbins again!
Excellent video 👍 I'm not a biker, been looking for explanations about floating discs for sports cars, and indeed most videos on YT are either unclear or plain wrong. This one is all I needed. And I promise, if I ever mount floating discs on my car I will leave the f*cking bobbins alone!!! 😉
I don't get it. I would say, cleaning bobbins it is pretty much same case as cleaning your caliper pistons. Remove the dust/dirt, so the whole thing don't get stuck. When there is enough of dust or dirt between the bevel washer, bobbin and disc, it might limit the space to expand...leading to bending or w/e other problem. Isn't it?
We'll do a follow up on this, but you're talking dust here. The SV's bobbins have probably not been cleaned out in years - we'll have a look
So my question is why do brembo discs have free floating, fully rotating bobbins? Im holding a set in my hands now and the bobbins rattle about like a goodn. Also there is 0.7mm of sideways movement from disc to disc carrier so im presuming this is to allow the discs to float in all directions
"So my question is why do brembo discs have free floating, fully rotating bobbins?"
- Usually because they're intended for racing and therefore get hotter. The point its that bobbins don't have to rotate or in another way of putting it - bobbins don't have to rotate to work properly
You always make me laugh with your choice of words, but I reckon your a clever guy and know your subject well..thanks for your videos.
In the VFR1200 Owners world I have been arguing with loads of guys who are obsessed with cleaning the bobbins out. They are convinced that the small vibration many owners eventually feel in the front brakes are due to the bobbins "seizing," when in reality the pad clips and slide pins are overly contaminated with brake dust from the sintered pads. When my bike developed a small vibration, all I did was take my calipers off, took the pads out, and cleaned all of the brake dust buildup off all of the pins, pistons, and clips, put it back together, and lo and behold it was nice and smooth again. Maybe you should cover that concept in a video? My own words fell on deaf ears.
Already have.
@@dirtygarageguy I guess I better go back and pay more attention. Woops
Matt your channel is brilliant. never heard of a requirement to rotate bobbins either. Is their "logic" behind the concept to alleviate the result of wear caused by explanation at 15:50 ? because I could understand the thinking, and that obviously wouldn't be an issue with the EBC model. But my old 99R1 has 130K on the clock and original discs and there's no issue with the bobbins.
Great informative video, thanks for the upload. Maybe you can help me with an issue I have. I just replaced my 2 front discs as the old 2 were ridged and well below the minimum wear limit. 2 brand new MTX MDF05001 discs and EBC pads for both discs. Less than a month later the bike failed it's MOT due to excessive fluctuation in the front brakes. The Tester said he suspects the discs are warped but when I checked them with a Dial Test Indicator the run out is 0.09mm and the max permitted run out according to the manual is 0.3mm so well within spec. After inspection of the 4 pot callipers I noticed that the seals on some of the pistons are blowing out through the space between the piston and the aluminium calliper body. I've replaced both callipers and am taking the bike down to see if this has fixed the fluctuation before we retest it. Would the blown out seals (which were not leaking fluid) cause the pistons to hang and in turn cause the fluctuation in braking effort? I can not believe that the new discs are bad unless of course they were poorly surfaced during the manufacturing process and there are areas of rotor that are thicker than others. Bike is a 2007 Suzuki GSF650 SA. Thanks in advance for any insight.
You need to make a special video where you see how quick you can get round a bike pointing out parts of the bike and then do the people's stupid stuff so point to the brakes and be like no copper grease, no fucking about with floating brakes, engine no hard brake in, no stupid turbos, wheels, no car tyres.. etc.
See how many you can get in an average sort of 15 minute video.
Having seen the breadth of your knowledge on this stuff undoubtedly you're right ..however ..years ago I had an FJR 1200 which failed MOT due to front brake judder. When I examined the disc it seemed slightly cocked due to what I thought was misaligned bobbins ( thought some had seized) Anyhow..cleaned them all up thinking the caliper will auto align the disc as a result . Took it back for a retest and it passed! Is it not possible for some disc/bobbin interfaces to seize after movement thereby resulting in what I thought had happened? Cheers anyhow Matt..... your Knowledge is rarely available to wannabee mechanics like myself and much appreciated . Bill in Exeter
I swapped my front tire and wasn't too careful with the rotor, and afterwards I noticed the outer part of the left brake disk now has a lot more play than the right outer brake disk (1-2 mm side to side). Is it faulty and do I need to change them or will it "tighten" over time and nothing to worry about? It brakes fine.. great content Matt, thanks
Push it down the street and pull the brakes to stop. Do this a few times and see if it gets any better
Glad to have found this channel
Hi Matt, I've an XJR1300 (twin discs, four pot callipers) and when I brake, the front end judders badly. The first thing I assumed was warped discs but I've ruled that out. I've seen the videos on cleaning the bobbins to eliminate judder so guess what..... I did it. I used tons of brake cleaner and spun the bobbins (they are still very tight). Result....... drastically reduced juddering. It's not completely gone though. Any ideas why it helped?
Loads of people say the opposite - so for your case I don't know, unless you had some real shit in there like a small stone of somthing that was causing the disc to flex. Did you clean your calipers at the same time
No, I'm gonna strip down and refurbish the callipers later in the winter.
Also had this issue on a 2017 GSXR with bad judderring : pulsating through the lever on hard braking. I cleaned the bobbins with massses of brake cleaner and has made a massive difference. But as per the above, I’m not clear why.
I'd been hoping you'd cover this. I recently got into an argument with a total cockend at work who was arguing you should remove the wave washers in order to, I shit you not, "let the discs float better". He'd replaced his bobbins, at great expense, and fitted them without washers, his front discs made the horrible rattling noise of impending failure.
I despise floating calipers. A great idea in an ideal clean, sterile world. As soon as there's so much as a mouse's pube on the pin, you get uneven pad wear. And binding. And squeaking
Bernoulli’ theorem, “an increase in the speed of a fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid’ potential energy”
A true liquid cannot be compressed.
I think I remembered that correctly please let me know if I screwed it up.
This is why I hate late braking when I see it. People believe that leaver or peddle will stop them without understanding the dynamics of braking systems.
These classroom videos are brilliant, thanks.
"A true liquid cannot be compressed."
- Anything can be compressed, like steel. The extreme of this is a neutron star
The Workshop,
Ok if I remember this correctly, once you apply enough pressure to a liquid due to thermodynamics and fluid dynamics (hand in hand with each other) with the pressure increased the fluid becomes a solid.
As we understand gas being compressed in to a liquid form this produces heat then as the gas becomes liquid it cools and eventually freezes in to a solid. If of course the pressure is still applied. (Fridges & freezers)
So within the braking system as the pressure increases, the fluid acts as a solid, Producing heat as a result. This is of course why the type of fluid used in braking systems has a low content of impurity’s “true liquid” (air water molecules) “and is why I want to smack the shit out of people when I see them pick up any type of hydraulic fluid and shake it.”
Did I remember it correctly?
And thanks for your time Matt.
Dell told me to put some olive oil on brake pads to protect them burning
I thought it was to make them taste better
Once the disks are burned and you've sanded your sidewalls it makes you look like you've won a few superbike races
@Slutty Mc'Slutface what about sunflower butter?
I understood that if it is an Italian bike then it must be olive oil
Makes sense, gravy is the national dish of Italy
I was under the impression floating discs are also used to help with pad knock off from high lateral cornering forces.
The effects of pad knock off / knock back are easily felt as a soft brake pedal on the first application after the knock back.
In older Subarus for example with the smaller hubs. When they changed to larger wheel bearings and hubs, the knock back was reduced as the larger bearings and hubs were more rigid to lateral deflection.
My understanding was floating rotors help with reducing the knock back as they can deflect laterally in opposition to how the hub/wheel/wheel bearing deflects due to lateral cornering.
Can you confirm if floating discs have this benifit???
Bram Biesiekierski The force required to deflect the disc is WAY higher than that required to push the Pistons back in their bores. Also, have never had noticeable pad knock off on a track bike, that wasn't caused by a bent/warped disc. That is on OEM brake discs in good condition. I can't speak for GP bike brakes, no one will let me on one 😂
Max Power
I was more specifically speaking about cars hence the Subaru example.
When bikes turn, they tend to lean into the turn, so there arent the same lateral forces that an upright wheel like on a car would see.
Bikes go round corners better than cars, but bikes can lean over, so the largest component of the force is inline with the bike vertically. Cars wheels have to stay near vertical when turning, and there is such massive lateral loading because of the vehicle wieght.
In cars pulling higher G corners, this loading can cause massive deflection within the bearing/hub relative to the upright the caliper it is connected to. This movement can cause the disc to knock the pad back inside the caliper as everything flexs. So the next time you apply the brakes, you have to give the pedal a double pump to take up the slack.
@@BramBiesiekierski which car has floating brake discs? never heard from one
Pad knock back is another load of b*llocks. The disks should run true otherwise there would be judder or lever/pedal pulsing.
Bob Barrett, Pad knock off is not a myth, it only takes a barely perceptible warp to push the pads/Pistons back far enough into the bores that the initial bite point is further into the stroke of the master cylinder, especially on cars due to the long brake lever (pad) travel.
Saved me a job to do this winter....cheers
Thanks, very interesting to know how things are made and what they are made for.
I discovered your channel recently but already watched many of your videos.
Greeting from France
Welcome to the channel dude
I agree but there exceptions , I own two Triumph Trophy’s one I’ve owned for over 12 years and never cleaned the brake bobbins , no linked brakes , the other is another trophy with LINKED brakes if only operates two pistons on the front calliper when operating the rear brake , you have to clean the bobbins in a regular basis or the disks will warp . So even though matts correct in this circumstance he isn’t .
I found videos on cleaning bobbins from searching for brake pulsing. My 2003 Kawa Z1000 has 6k miles on it. What's the most likely problem for brake pulsing? You can feel it throughout the stop, not just slow stops. Thanks from West Virginia!
Pulsing is usually a mis-aligned caliper or shit on the disc. In very few cases its a warped disc
@@dirtygarageguy thanks for your reply. Looking forward to a UK visit someday. I've also seen a variety of "cleaning" recommendations anywhere from 800 to 150 grit sandpaper. What say you Sir?
150 would do
I love your content when you're not fucking around with certain wankers and actually teaching us. Keep it up 👍
Another thing I didn't know I didn't know 😀
Great explaination.
is that dirt and shit in your rear caliper? or that paint already shite the bed?
You are amazing and take away a lot of my concerns raised by these other channels (not naming anyone in particular....) thank you Matt!
Another reason why I'm glad you have a channel...to weed through all the shite people are putting out there that could possibly get you killed or injured. Bravo my friend
Thank you guy at cadwell park track said about doing that bolt thing glad I’m too lazy and never got round to doing it roll on Mallory park on me Zx9r
Really good info. Thanks
I dont think Matt mentioned them specifically but if you have EBC SD floating rotors you will likely BREAK something if you attempt to turn them as they arent a circular 'shape under the bobbin cover ( which is actually the unique selling design point ), they can only move outwards or inwards.
They're in this video
@@dirtygarageguy I 'm a muppet, I kept watching and saw the section where you did mention them now ...
I just bought a 2009 Concours 14. When I hit the front brakes the bike shakes pretty bad. Oddly enough, I don't feel any pulsating in the brake lever. The rear brake feels just fine. The motorcycle does stop and stop well, I don't get why it shakes only when I hit the front brakes. Do you have a suggestion for me?
When you say the brake shakes, what shakes exactly?
@@dirtygarageguy I mainly notice the windshield vibrating when I hit the front brakes.
That could just be a dodgy windshield, does the whole front end shake?
@@dirtygarageguy yeah it does. Apologies for the late reply. UA-cam never notified me of your reply.
Dude you are riding the struggle bus. Take the day and start again tomorrow lol
Best video about " Floating Brake Disc " Thanks 🍕🍻
I have 4 or 6 pairs of perfectly usable original RGV 250 disks from 1989/ 1992. However the bobbins are all loose and rattling. Are the disks usable if not is it worth doing anything with them? Do I need to bother / worry, get a brain?
eBay them - make it someone elses problem
@@dirtygarageguy that's how I got the fecking things ;) Ok new brain it is then ;)
Great vid. Quick question and hopefully you can help me. I have the Arlen Ness G3 Floating Brake Rotors. I happened to notice the other day that the Front Brake Rotor hardware kit (Screws, washer and lock nuts) are loose (Some play) while installed, I figured I'd tighten the screws and that'd be it. However, this did not work as they are all in (Tightened to the max) Bottomed out. They are still lose and flimsy which makes the disc wiggle quite a bit. Aren't these supposed to be firm and sturdy while installed and doing their purpose between the brake disc and the carrier? Please advise..ty
Sounds like the bolts are not fit for purpose You need to contact Arlen Ness
@@dirtygarageguy thanks brother
Ive just fitted brand new Brembo Serie Oro disks to my fazer and the buttons/bobbins rotate freely. In fact, the whole outer portion of the disk can be rotated by hand there is so much free play on the buttons. I assume this is a design feature and not a faulty set of discs, but you have me worried now saying that they aren't meant to rotate. HELP!
For race type discs the clearance is great because of higher temperatures etc.
"but you have me worried now saying that they aren't meant to rotate."
- you've misunderstood. They're not designed to rotate - in otherwords bobbins don't need to rotate to function. If they do, they do and that's fine. The point was if they don't they're not borken or anything.
The Workshop that’s reassuring. Thanks so much for the reply, much appreciated.
@@dirtygarageguy.. Could it be brembo has 2 systems of rotors /bobbins.. Have an 15 year old Brembos, and have a such noise in the calipers, that I can't stand it.. No ride for years.. Always from New these Bikes with Brembos have the shitty noise.. They did get fixed just after a couple k miles.. Then the noise appeared.. Worsened in rain also.. Today, useless..
Thank you Matt ❤😊
I tried this on my semi-floating bobbins due to a pulsing brake sensation that was glaring at low speed and it fixed my issue. Wondering how come it worked? The braking feels much better now with no bouncing/pulsing.
Semi floating?
@@dirtygarageguy not sure tbh.. they're not as laterally free moving as some rotors ive seen. all i know is the pulse is gone.
you are clearly a smart guy
Hi Matt
Thanks for the explanation much appreciated , i just got a Tiger Sport with 14,000 miles on the clock pads are fine no grooving of the discs but i get vibrations as soon as i pull on the front brake lever whether on first braking on setting off on a run or whether later on when everything warmed up , any thoughts on what could be causing this and how to fix it ? Thanks .
Warped
So my motox has quite a lot of slack in them, is that bad and i should replace them?
It depends on how old they are, who made them and what they were like to begin with
Best explanation - EVER. Thanks.
Great explanation, always thought about how they were designed to work properly 👍
Great stuff... Learned so much today.. Thanks.. Keep the good work coming💪👍
I’m guilty of seeing one of these bobbin cleaning videos and believing I need me some of that early on in my biking career. Took an age....... did fook all........ never did it again
Matt you need to be a teacher your drawing are mint
He is my teacher
Do fixed calipers work noticeably better than floating calipers? I've never ridden a bike with fixed calipers.
Good vid. I've actually seen posts from guys doing the nut, bolt drill thing and about the crap that comes out when its flushed with brake cleaner. Thats metal thats being removed! Anyway good vid.
If it was metal coming out, it would be bright. If it's anything else, it's a combination of road salt and oxides of one or more of the metals which the component parts are made from. These will build up over time and reduce the parts ability to freely move back into their original position under the tension of the spring. They come from a process called 'galvanic corrosion' which occurs as a result of 2 different metals being held together.
PFM floating discs, no bobbins, brilliant design and (British) made in the Isle of Man.
Gotta love your no nonsense approach 👊🏻👊🏻 must be a northern thing! 😎
Question. From new the bobbins are free.
With time, dirt, rust and grime will seize the bobbins in place. Not allowing the disc to move expand etc. It's bad to free the bobbins times to times? Would this not avoid the discs to warp?
Cheers and thanks for the video.
"From new the bobbins are free."
- But they're not...
"With time, dirt, rust and grime will seize the bobbins in place."
- Again they're not, some are but not all.
"Not allowing the disc to move expand etc."
- But this is where the problem lies. The expansion is radially outwards - if the clearance is reduced then the brakes expand in the other 5 degrees of freedom...
"It's bad to free the bobbins times to times?"
- The shit in the bobbins is brake dust mainly, an abrasive material. Twisting the bobbins in their clearance grinds the clearance larger, which isn't a good thing.
"Would this not avoid the discs to warp?"
- warping the disc requires heat, a shit load of it. And like I show in the video some bobbins aren't round, so they can't be rotated.
My issue with this is that not all things are the same. So if u have a disc with free bobbins from factory and they get seized it's normal to leave them seized??
And some are solid others need to move from side do side once they have a type of spring wash to allow movement. But as u showed there's a new type created by ebc that doesn't move.
It's just a bit of everything and makes a lot of confusion not for me but for many people out there.
Another thing I understood and you mentioned is the gap gets bigger once u start spinning the disc each obviously can make the disc to move excessively.
But for the discs that originally come with free bobbins should u keep the bobbins clean so they don't seize.
Thanks for your time and help.
"My issue with this is that not all things are the same. So if u have a disc with free bobbins from factory and they get seized it's normal to leave them seized??"
- You say seized. Seized means not moving, which implies that it should in the first place...
"And some are solid others need to move from side do side once they have a type of spring wash to allow movement."
- The wave washers are there to stop the bobbins moving. This is how it breaks down.
The disc will expand in all 3 dimensions which includes axially. The bobbins have to have clearance otherwise if they were tight they'd pop of wheb the disc heats up and expands. So there's clearance. But this clearance means that they can rattle around due to the disc vibrating when the pads clamp on.
So to stop this from happening wave washers are added to apply a pre-load. This stops or supresses the vibration by absorbing the energy. When the disc expands it compresses the wave washer with little resistance.
"But for the discs that originally come with free bobbins should u keep the bobbins clean so they don't seize."
- But again that word seize.
Matt, is it possible to use floating rotor with floating calipers?
Yeah, because they're not the same thing.
@@dirtygarageguy thanks for your reply! yeah, I know... Just asking It floating+floating could cause any issues.
Hey!! Hang about! fuck off!! LMAO 3:21 awesome! Great Video Matt thank God someone gets it right, shit drives me mad!
Wasn't the whole point of rotating dusk bobbins to clean out road shit so the bobbins don't seize and cause the disk to warp? Even in Del's video he specifically said this. I've watched other videos on this too and it's all about cleaning them, not "giving the bobbin the ability to rotate with normal use."
My front brakes vibrate like hell, as i brake the front light bumps up and down when riding in the dark (for example. Are my calipers twisted for some reason or doesn't the bobbins just let the caliper move at all? bike is ninja zx6r original brakes just like in the video
Can you send me a video by any chance?
@@dirtygarageguy yes i have some gopro footage I'll find a good clip to demonstrate! Thank you
@@dirtygarageguy ua-cam.com/video/lIVA5zuHccw/v-deo.html here is 2 clips the last one is little better explaining the wiggle. I ride on a steady road and press stably on the brake lever
Do you mind if I use the footage. Would make a great video - First things first - take the pads out and look for a build up of shit on the surface, then look at the rotor. Black shit stains are what you're looking for. You can use 400 grit sand paper and lightly remove at the shit. Try that and if you can send me some pictures of what you find. This usually happens if you brake hard and keep the brakes on when stopped.
@@dirtygarageguy You can use it sure! But alright I'll take a look, pad are fine but not sure about the rotor
I always had a feeling it did nothing, I cleaned them out once it took ages and ultimately made zero difference lol
At the risk of being 'picky'. Is that scratches against the bleed nipple? On a brand new bike?
LOL no. That's paint marker - there's a few spot around the bike like this - this is for inspection at the factory to makes sure these fitting have been torqued and then checked before testing - so in this case for the brake system before brake testing
there is one in the bleeding screw/valve that doest look like paint for torke-check.
How do I tighten the bobbins mine have alot of play
You can't and don't.
please help. i have floating calipers hovever the floating pin stuck in the caliper.. and no force can move them again. any idea how to free them? special tool to push it.. ??
A punch and a hammer
"Just fucking don't" thank you i am delighted to learn there's something on my bike i wont ever have to fuck around with - halleluljah
Does it matter if they’re rusted?
"Does it matter if they’re rusted?"
- yes its called clean your fucking bike - buy some new ones and this time stop being a lazy bastard
But Matt, I wanted to replace my bobbins with gold ones because Gold conducts heat better!!!!!!!!!!!!!!!!!!! 😜
Just donemine on the big zed as was worried I had warped discs, so I did clean then out, and rotate them...just me...fubard! (must say the discs seem better and now can move under thermal expansion,,, loads of crud in them.
I believe there is a spec for the bobbins in regard to how much free play they have to be safe
where? Its a geniune question.....
@@dirtygarageguy Its probably one of those mythical quotes that always goes "refer to the service manual" but a google around does come up with an EBC page with a reference ebcbrakes.com/product/floating-mc-rotors/ "Both Floating MC rotors feature mill hard stainless steel high friction rotor blades for maximum brake effect and are direct size for size replacements for OEM rotors. Both designs are also true ful"ly floating units, offering more inside to outside float tolerance than any other rotor on the planet.
Do not confuse floating rotors with rotors that feature loose rotors blades or buttons. You should not be able to move either the buttons or rotor blades from side to side, if you can, it is highly likely that pad “Knock Back” will occur and you will end up with spongy brakes. Float means outside to inside heat expansion ability. That is what EBC X and XC rotors deliver and no other rotor can.
Always use new pads when replacing rotors, the use of old or worn pads can cause hot spots or glazing of the rotor and will promote brake fade and loss of brake.
I tried to tell a mate this once, even showed him the solid bobbins on my Ducati discs. But because curls for the girls Ari said you should do it, he takes that as gospel
You should teach Matt , your lectures would become legendary !
Completely unrelated in any way whatsoever, but I’m interested in what a 2 Stoke doxer engine would be like if it would even be possible at all it would probably be very flooded and unreliable but I think it would be something magical.
i think the germans in world war 2 had a 4 cilinder 2 stroke boxer engine on a motorbike, so i guess it could work?
One word, Konig.
The most orgasmic sounding Engines on the Planet, and yes, that includes the Norton Rotaries.
Get to a Classic Bike Race Meeting and hear one for yourself . . .
ua-cam.com/video/A0BwMeRTQ0E/v-deo.html
Just an extra comment but it does seem weird that there are so many stories of people successfully fixing "pulsing " at the lever by freeing the bobbins? Just an observation that seems odd from what you are saying.
This is probably because they cleaned their brakes at the same time
"The Workshop" mentioned brake disc expansion. He ignored that brake disc expansion is not uniform in all directions. A brake disc can expand. and get slightly curved. The bobbins help account for errors of a warped disc. When the warped part of the brake disc enters the brake pad surface, a un-seized brake bobbin will shift left or right to account for the warped disc position.
Now imagine if the brake bobbin is 100% seized. And the warped brake disc is now entering the brake pad region. The bobbins are 100% seized, no movement. The warped disc enters the brake pad region, and because the disc is warped and curved and the bobbins are seized, the brake disc does not shift left or right, but instead keeps its misaligned position and presses harder against one side of the brake caliper for a split second. One side of the caliper is now complying and getting pushed in slightly and causing a pressure jump if your brake line. and you feel it in your brake lever.
My Personal Experience below :
Problem: Pulsating front brake lever under repeated hard braking.
Fix: Un-seize the front rotor bobbins using the "bolt through bobbin" technique to loosen what ever cause it to seize up. The bobbin shouldn't be 100% free spinning, but you should be able to spin it with a T-handle or a screw driver. (You cant spin them like he did in the video using your fingers, no ones fingers are that strong. and the bobbin will be too loose at that point).
Test Drive: After loosening up the seized bobbins go for a test drive on the same road. Front brakes are no longer pulsating.
1 Problem . 1 Repair. 1 Problem solved.
I would of loved db's to try an get that fact oot!!!🤣👊
What about my rsv mille rear brake solid mount caliper and disc get leveled out by the pistons?
Levered out? I don't get what you mean? RSV calipers are floating calipers - on sliders......
@@dirtygarageguy leveled as in how the floating caliper would centre itself do they just push more fluid to whichever side
They are solid no floaty rubber bit solid mount on bracket that goes through axle I'll send some pics
I remember on me bandit. The bobbins were really stiff and it cause my disc to
Stop floating.
Stop floating where? LOL
One disc was ridget. Until I got the bobbins moving. Then there was slight left/right movement
from the disc.