CBR 600 FX front brake problemo

[sunbear]

Hey fellas

Some of you may have seen my ad in the bikes and accessories listings. Here's a quick run down of what I am experiencing :

Front brake slows the bike down fine. At around 20mph and lower however, the front of the bike judders which gets worse as speed decreases and sometimes a "grinding" noise comes from the front wheel. Now, I thought it could be warped discs, however I get no pulsating through the lever. I have also had the front wheel in the air and the discs seem straight when turned. Everything is nice and tight.

The problem very temporarily disappears after I have removed the calipers from the disc and pushed the pistons back to get them back on to the disc. But after a mile or so they go back to the juddering business. With the front wheel up it does not spin very freely.

Any ideas where to start looking ? I have no idea about calipers and stuff.

Cheers
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Bikes had : BMW F650, suzuki tr50, gt125, SV400, GSXR600 SRAD. Honda CBR900RRP, CBR600FX, CBR1000F, VT600, Transalp 600, mtx125, nsr125r, CB500T, Yamaha fy50, tzr125, tdr125, XV535, Diversion 600, Fazer 600, TDM850 MK1 & MK2, Majesty 400, XV 1100. Cagiva mito evolution, Aprilia rs125, Piaggio x9 125. DNA 125 . Suzuki Bandit 600, GZ125 Marauder, RF600 , RF900RS2, Kawasaki ZZR400, ZX6R Ninja, ZZR600 . Ducati 750 Sport . Triumph Tiger 955i. CURRENT : 2004 Kawasaki Z750 and LOVIN IT !

[Noxious89123]

I have an F-Y and have EXACTLY the same problem. Had the problem with the standard discs and pads, and again with my EBC discs and pads.

Then front wheel will always have a little bit of drag as the pads are always in contact with the disc.

What pads are you using? I'm using EBC HH Sintered pads atm.
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'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[ZaphodBeeble]

Probably corrosion built up in the calliper dust seals. The pistons are not returning fully when you let go of the brake lever. Personally I would pump all the pistons out and remove the dust seals to scrape all the corrosion out. Use red rubber grease to lube them back up when re-fitting. Remove a calliper and take some pictures with the brake pads removed from said calliper.
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Current bike: VTR1000F Firestorm. Previous: Firestorm (written off) - XJ600 Divvy - NSR125 - DT125 and a load of offroaders.

[Noxious89123]

Doubt it's that, I had my calipers split and cleaned just before winter, a few weeks after I'd had new discs and pads fitted and it was still doing it then.

I also recently had my calipers off and cleaned some of the crap off the pistons and put a little silicone grease of them. Doesn't seem to have made any difference.
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[alun111]

Are you sure it's not tyre grip/headstock bearings/suspension/wheel bearings problems?
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Summer: '00 Honda CB600F Hornet
Winter: '93 Suzuki GSF 400 Bandit VP Variable Valve
Past Bikes: Lifan LF100-5 Lifan LF125-A Honda C70

[sunbear]

Tyre grip is fine, new wheel bearings just before I had the bike, headstock bearings seem OK to be honest. The handle bars turn freely with no notchiness with it off the ground.

I am stumped !
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Bikes had : BMW F650, suzuki tr50, gt125, SV400, GSXR600 SRAD. Honda CBR900RRP, CBR600FX, CBR1000F, VT600, Transalp 600, mtx125, nsr125r, CB500T, Yamaha fy50, tzr125, tdr125, XV535, Diversion 600, Fazer 600, TDM850 MK1 & MK2, Majesty 400, XV 1100. Cagiva mito evolution, Aprilia rs125, Piaggio x9 125. DNA 125 . Suzuki Bandit 600, GZ125 Marauder, RF600 , RF900RS2, Kawasaki ZZR400, ZX6R Ninja, ZZR600 . Ducati 750 Sport . Triumph Tiger 955i. CURRENT : 2004 Kawasaki Z750 and LOVIN IT !

[Noxious89123]

[Noxious89123]

Done a bit of searching on Google, and there seems to be quite a few ideas floating around about this.

The main thoughts seem to be head bearings or warped rotors. As we're both sure neither are the problem, I've been reading more into the other ideas people have.

A strong possibility could be cooked / glazed brake pads. Convieniently, I have photos of my pads;
https://img30.imageshack.us/img30/4277/1000812k.jpg
https://img37.imageshack.us/img37/3994/1000813.jpg
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[sunbear]

Those pads resemble mine, but mine arn't as scored as yours seem to be . I cannot check the tyres or pads at present (at work)
____________________
Bikes had : BMW F650, suzuki tr50, gt125, SV400, GSXR600 SRAD. Honda CBR900RRP, CBR600FX, CBR1000F, VT600, Transalp 600, mtx125, nsr125r, CB500T, Yamaha fy50, tzr125, tdr125, XV535, Diversion 600, Fazer 600, TDM850 MK1 & MK2, Majesty 400, XV 1100. Cagiva mito evolution, Aprilia rs125, Piaggio x9 125. DNA 125 . Suzuki Bandit 600, GZ125 Marauder, RF600 , RF900RS2, Kawasaki ZZR400, ZX6R Ninja, ZZR600 . Ducati 750 Sport . Triumph Tiger 955i. CURRENT : 2004 Kawasaki Z750 and LOVIN IT !

[Noxious89123]

My discs seem to have alot of dark crap on the surface of them, with the odd light shiny line round them, so I think it must be from cooking the pads.

What is the best way to wear this off? Light braking, or heavy braking?
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[Bofh5]

ive got a 95 FS and get the same sort of thing as well.
Is it like this example: Travelling along at say 70 and need to stop so apply brakes everything is fine then just before you come to a stop it feels like the front wheel is juddering almost as if the brakes are like abs (sorry crap example).

I changed my wheel bearings checked the headstock and had 2 mechanics look at it none of which could tell me anything.
I have some new carbon ceramic pads to put in soon so will see if these make any difference.
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(L)users...Disk space is to good for them.

Bikes: Honda 50 / CB125-TDC / 93 CBR600 F2 (Stolen & Trashed) / 2001 SP-1 (Sold) / 95 CBR600 F3

[sunbear]

Yep, thats what happens with my bike too. Is this just a CBR thing ?
____________________
Bikes had : BMW F650, suzuki tr50, gt125, SV400, GSXR600 SRAD. Honda CBR900RRP, CBR600FX, CBR1000F, VT600, Transalp 600, mtx125, nsr125r, CB500T, Yamaha fy50, tzr125, tdr125, XV535, Diversion 600, Fazer 600, TDM850 MK1 & MK2, Majesty 400, XV 1100. Cagiva mito evolution, Aprilia rs125, Piaggio x9 125. DNA 125 . Suzuki Bandit 600, GZ125 Marauder, RF600 , RF900RS2, Kawasaki ZZR400, ZX6R Ninja, ZZR600 . Ducati 750 Sport . Triumph Tiger 955i. CURRENT : 2004 Kawasaki Z750 and LOVIN IT !

[Bofh5]

When i put the new pads in i'll scrub the discs and give the callipers a good clean and see how it goes.
Not really a huge problem more irritating than anything.
____________________
(L)users...Disk space is to good for them.

Bikes: Honda 50 / CB125-TDC / 93 CBR600 F2 (Stolen & Trashed) / 2001 SP-1 (Sold) / 95 CBR600 F3

[sunbear]

At the end of the day the front slows me down, and the back brake will bring me to a stop. But as you say, it can be iritating. Would just be nice to find out what causes it !
____________________
Bikes had : BMW F650, suzuki tr50, gt125, SV400, GSXR600 SRAD. Honda CBR900RRP, CBR600FX, CBR1000F, VT600, Transalp 600, mtx125, nsr125r, CB500T, Yamaha fy50, tzr125, tdr125, XV535, Diversion 600, Fazer 600, TDM850 MK1 & MK2, Majesty 400, XV 1100. Cagiva mito evolution, Aprilia rs125, Piaggio x9 125. DNA 125 . Suzuki Bandit 600, GZ125 Marauder, RF600 , RF900RS2, Kawasaki ZZR400, ZX6R Ninja, ZZR600 . Ducati 750 Sport . Triumph Tiger 955i. CURRENT : 2004 Kawasaki Z750 and LOVIN IT !

[temeluchus]

you seem to have covered most propbabe causes.

One thing to look at is the brake disc bobbins holding the disc to the hub. They can corrode and cause odd sensations-perhaps you disturb em and they free when you get the caliper off and then return to a bad state after a few miles after refitting.....
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Some shite cruiser. Now with guns and FREEDOM!

[Noxious89123]

I have found the cause of the problem.

According to the internet, if you overheat the pads, they will deposit a fine layer of friction material on the surface of the disc. The adhesion between the pads and the discs is increased by the material stuck onto the disc, and so you get this juddering feeling at low speed.

I've been out for a ride recently, and using the brakes relatively lightly has removed the deposits from the surface of the disc.

The disc surface looked slightly darker, where the pads had left stuff on the disc.

Seems to fit
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[maximi1ian]

This brake judder has just started happening on my 2003 CBR600RR

It only occurs when braking hard from low speeds, eg 15mph-0mph. When in traffic etc. A violent vibration through the front forks that shakes the fairing and bars. Note: No feedback through brake lever.

Therefore I cannot see how it can be a wharped disk as so many people speculate. As it only happens very occasionally, and at low speed only.

However when it happens I immediately thought: Problem with brakes, its like one of the pads is vibrating in the caliper, bouncing off the disk, like it got stuck on the caliper pin and was at an odd angle (if that makes sense.)

The only changes to the bike I have made recently are increasing tyre pressures to 36/42, from 30/36. And softened up the rebound and compression.

Noone seems to have a definative answer to the problem but I will start by trying the suggestion above ^^ (cleaning disks). Also cleaning out the disk rivet/bobbins. Then I shall reset the front forks to the standard settings.

[TUG]

Juddering? Has anyone tried changing the fork oil in their bikes?
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Haz ER-5, innit!

[0l0dom0l0]

[maximi1ian]

I just got back from a 20min test ride after cleaning out disk bobbins/rivets, a rinse with water and having reset the front and rear suspension to factory settings.

I was trying to prompt the bike into juddering by continually braking from 15mph or from 30mph, and even trying some higher speed braking (40/50mph) and I couldn't make it judder once.
Unfortunately this isn't conclusive because it only used to happen occasionally, so after a few hundred miles i'll post an update but it looks good so far.

Assuming juddering is eliminated, I suspect that the suspension alterations have made the difference as it certainly feels a lot firmer and more bumpy since I made the changes. I had previously dropped the rebound and bump stiffness and I noticed that both front and rear the preload was set softer than factory settings (previous owners doing). Perhaps I was bottoming out the front shocks?? I am 6'2" and 85kg so I imagine the low front preload wasn't doing me any favours.

Still, to anyone experiencing this problem I would reccomend going through these stages before replacing various parts.

P.s

After cleaning I noticed some rotational movement (circa 1mm) in the brake disk (play in rivet/bobbins) is this normal? My hornet has no play whatsoever.

I am running road pressures (36/42) on pretty scrubbed Dunlop Qual. RR's and factory forks, pads just replaced (Brembo Sintered), fluid changed and calipers cleaned recently. No noticeable head bearing play.

[Noxious89123]

Shouldn't be the forks, mine have been rebuilt with new oil and seals. They also feel sweet, not harsh and bumpy, or soft and wallowy.
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi