Blue spot brake seals???

[OGRI]

Yamaha may already know did you ask them, the corrosion from the collector box does creep up the downpipes, you can see it on another thread.
Fortunately the entire exhaust is not always wet, like inside a braking system, to accelerate the process.
The accident I spoke of in that car was a deformed piston, I had to replace it for new, as it would keep hanging up even after through cleaning, probably the intense heat kept making it get cocked in the bore afterwards.
As for bollocks, well done is that your only opinion.

[OGRI]

The fluid does not take all its debris in one go. It gets shaken up by bouncing over the road surface then deposited little by little, all over the internals. Gravity will cause sediment to settle and then it gets shaken up all over again, on the next ride. Migration I suppose you could call it.
Yes keeping it clean is the key, to most everything.
Water is probably the main culprit from the atmosphere, it causes all kinds of crud to fester and go nasty. In an enclosed system it seems to get magnified.

[nugget]

Right lads.

I've spent most of the day in the cave sorting this binding problem.

YAMAEXUP wrote...Yes, the washer does go in place before the circlip, round face inwards. That way the spring pushes against the washer & not the circlip.

The first thing I had to do this morning was to change the washer the right way round, luckily for me I hadn't put any fluid in the reservoir so it was only a two minute job. Got the brake lines bled and got good pressure on the lever.

I put the scissor jack under the header collector box to raise the front wheel slightly off the floor and spun the front wheel and it was still binding.

Scratch of head and thought I'd start at the brake pads again and make sure there not sticking anywhere. After a good check and clean up. I pumped the pistons out with the lever then and made sure they pushed back in by hand which they did.

I then reassembled the pads the same way as they came out of of the each caliper. Got everything tightened up and pulled the lever to get the pressure back up again. I then spun the wheel and it wasn't binding as bad as it was half an hour ago so I don't know whats made the difference. The pads in the calipers were nice and loose and the pads are only halfway worn.

I'm having a ride to Whitby tomorrow so I'll see how they go.

I'll report back with how they go. .

[Stig]

Is the lever clearing the piston in the master cylinder when fully released

[nugget]

What am I missing????

I've been through all of the system. The only thing I haven't done is #1 fit some new pads, the pads I have in the bike now are only halfway down & #2 try some different discs.

In Whitby yesterday I had to park on the pavement near the Whistlestop cafe because the bike park section was full. (Stig might know where I mean) When it came to roll the bike backwards off the pavement you can feel a slight resistance on the front wheel as though it's not rotating freely enough. I had use your more leg pressure to pull it backwards.

On my way home I called at a friend of mine (Alan, who's also a biker) who runs a garage/MOT business. I told him what I've been doing recently with this job on the brakes and we lent the bike over on its side stand and he spun the front wheel and said there is a bit of binding/resistance but it's not bad and nothing to worry about, so I asked him if it would pass the MOT and he said yes. Alan thinks I'm overthinking it and I'm worrying too much. He knows I like things perfect on my bike and with it being the brakes I want them to be spot on.

Arriving back at home. I always start to clean the bike down before I do anything else. I raised the front wheel off the ground slightly to clean the brake dust off the wheel and when I came to rotate the wheel it took a bit of strength to get it to rotate it.

I'm at a loss now and it's staring to annoy me a little.

YAMAEXUP, I'm wondering whether to remove that washer that came with the kit and see if that makes a difference?

When I was bleeding the system and pulling the brake lever and cracking open the nipple etc no air bubbles were coming out of the tubes attached to the nipples.

Something else I noticed, every time I opened the nipple under pressure with the brake lever and then closed the nipple back up again it would take between 60 to 90 pumps on the lever to get any pressure back on the pads?? I have adjustable levers and it was on #1 which is the widest setting. Having to pump it that many times doesn't seem right to me.

Looking into the reservoir with the cover off, when your pumping the brake lever you can see the fluid raising at the point where its coming out of the return hole. It did squirt out a couple of times but I was prepared for that. When I let go of the lever you can see the return hole clearly. I've just been out to double check this and in fact there's two holes.

Well the weather is going to be shit for a good week or so, so I'm going to have to go through it all again. I don't think (worrying or not) the front wheel should be that hard to rotate.

I'll be back....

[OGRI]

Hello Nuggett, It sounds like a full or partial blockage somewhere inside the system, first resisting and then holding residual pressure.
The wheel should not be stiff at all to spin by hand. Just a slight touching sound, rubbing of the discs on the pads, especially if the disk has a little bit of throwout.
Lever pumps at those numbers, indicates not a full transfer of the fluid in each stroke. Whatever the volume pushed along the passages, can only be the same amount grabbed by the lever each time afterwards. So a small volume replaced by another short volume will equate to many lever strokes.
Did you feel for any heat on either caliper, wheel rim spokes and hubs. Of course be bloody careful when using your bare hand especially on the discs.
How are the wheel bearings ?
Without spending money on discs, pads, or wheel bearings possibly.
Go back to the beginning, to separate as many components as poss and blow them through with compressed air, being totally satisfied that all the tiny passages are flowing, inside the calipers, inside the brake lines and the reservoir passages too if you can.
What was the crud buildup like inside the calipers when you first looked inside, that will give you an idea of what maybe in the passages too.

OGRI.

[Stig]

I recon it's the mc at fault even tho it's been rebuilt

[nugget]

OGRI In answer to your question. I've done a couple of brake checks after braking and the discs feels warm but not hot. I have experienced a red hot disc on the hand and I won't be repeating it ever again. The crud build up in the seal groves wasn't to bad at all. I was expecting a lot more than what I go out and yes I was very thorough in doing the job, I always am. Buy cheap buy twice as my mum used to say.


Right lads. State of play is...

First thing I did yesterday was to clean the bobbins up by clamping two large washers together on the bobbins and squirting some brake cleaner at them on both sides of the bobbins & some crap came out as I rotated the two washers with an allen key. I did all both sides (20 in total) took ages but I was determined to get to the bottom of this pain in the bum.



Next job I did was to take out the pads on the right hand side caliper (sat on the bike) and pumped the brake lever to push out the pistons and they came out easy. After a clean up, they weren't really dirty to be honest. I pushed them back in also easy. I put the pads back in and put a screwdriver in between the pads and pumped the lever to check for pressure and there was. Did the same with the L H side caliper, when I came to pump the pressure up with the screwdriver in place again I couldn't get the same feeling of pressure the same as the R H side one had?? In effect the screwdriver was loose in between the pads. ??





After pushing back in the pistons. I put the calipers back on the bike and it took approx 150 pumps to get the pressure back on to the pads?? When I finally got the pressure I raised the front wheel off the ground and spun the wheel and for some strange and wonderful reason the discs or pads weren't binding like they were it felt normal again, you could here the pads just touching the discs as I rotated the wheel. I pulled on the brake lever a few times and continued to rotate the wheel and it seemed fine and free.

See video below. Sorry about the state of the carpet OGRI I'd just let the ferrets out of their cage and they dragged all the bedding with them.

https://youtu.be/4gqY0wsDjn4

[OGRI]

Hi Nuggitt, The vid looks correct from this side of the screen.
Bringing your brakes back to a safe condition is more than important, you know that already. It would bug the hell out of me too.
The LH caliper may well settle in by itself, would just keep an eye on that one, over your coming rides.
WHAT.... the ferrets sleep under a duvet, you are far too good to those little buggers.

OGRI

[Stig]

Nuggitt

The faulty caliper......

Try giving it a shake, insert some spacers/packing to stop the pistons popping out and then try rebleeding that caliper ensuring the nipple is as high as possible

Thinking is there may be air trapped that making the pistons creep out over time causing the binding youre experiencing

[nugget]

An addition to this saga.

I removed the right hand side caliper (sat on the bike) off the fork leg and slid the screwdriver in between the pads as before. Then pumped the brake lever and I have strong pressure on the left hand caliper which is still mounted on the fork leg.

I replaced the right hand caliper and did the same with the left one and I have good pressure on the right caliper.

I fitted the left caliper back on and had to pump the lever quite a lot to get the pressure back up to strength again in both calipers.

Something is telling me there is air trapped like you say stig. I'm going to have a go at that shortly. Thanks lads and I'll be back with more...

[nugget]

Nuggitt

The faulty caliper......

Try giving it a shake, insert some spacers/packing to stop the pistons popping out and then try rebleeding that caliper ensuring the nipple is as high as possible

Thinking is there may be air trapped that making the pistons creep out over time causing the binding youre experiencing

Right stig.

I've just come in from trying this tip of of yours & roadrunners, but we wont mention that.

I even manage to get the caliper higher than the reservoir. My neighbour Paul came in to help me pump the brake lever while I cracked open the nipple I'd filled him in with what was happening with the binding pads/discs etc so as he got the lever pressure up I cracked open the nipple and we were both expecting a load of air bubbles to come up the attached pipe but nothing only fluid we did this three times and no air came out. Every time I cracked open the nipple it took 100 ish pumps on the lever to get the pressure back up. Paul is a bit handy with mechanics and even he said it shouldn't take that many pumps. I noticed if you took large pumps on the lever it took 100 pumps but if you did small slow pumps it built up quicker???

I'm now wondering if it's that extra washer that came with the kit that's causing the problem??

I've had enough today so I'll have a go at taking that washer out and see if that makes any difference.

[nugget]

Right lads I bring good news.

I took the MC apart once again & removed the extra washer that came with the kit, and I'm pleased to say I can now get pressure between 30 to 40 pumps on the lever after bleeding the system with cracking open a nipple.

I've just been out for a test run and I did a brake test where I didn't touch the front brake lever and after a couple of miles I pulled up at the side of the road with only using the rear brake to slow me down, and jumped off the bike and gently felt both discs and they were both cold so no more binding. That makes me very happy so I'm going to put closure on this pain in the bum.

Thanks for all your input lads, and take note make sure if you need a washer or not in your MC? If a washer doesn't come out when you change it then don't put one in.

[YAMAEXUP]

Yamaha may already know did you ask them, the corrosion from the collector box does creep up the downpipes, you can see it on another thread.
Fortunately the entire exhaust is not always wet, like inside a braking system, to accelerate the process.
The accident I spoke of in that car was a deformed piston, I had to replace it for new, as it would keep hanging up even after through cleaning, probably the intense heat kept making it get cocked in the bore afterwards.
As for bollocks, well done is that your only opinion.

I'm not concerned about your car. We're talking bikes. If the piston comes that far out of the caliper then the pad must be missing.

And why would the inside of a braking system be wet???? Wet with brake fluid maybe, but not wet with water....

[YAMAEXUP]

The fluid does not take all its debris in one go. It gets shaken up by bouncing over the road surface then deposited little by little, all over the internals. Gravity will cause sediment to settle and then it gets shaken up all over again, on the next ride. Migration I suppose you could call it.
Yes keeping it clean is the key, to most everything.
Water is probably the main culprit from the atmosphere, it causes all kinds of crud to fester and go nasty. In an enclosed system it seems to get magnified.

Oh this is good. I must give this snippet to a friend the next time that he goes on stage at the comedy club

There's no way that debris moves up & down inside of brakelines with the movement of a machine over road bumps.

Try this as an experiment.... Place a piece of foam inside a clear glass jar filled to the brim with water then seal the lid. Make sure there's absolutely no air in the jar. Now give it a good shake Notice the piece of foam moving? No. i don't think you will. Now think of much thicker brake fluid & much smaller dimensioned particles. And you think that these minute particles are going to move up & down inside the brakelines every time you go over a road irregularity?