Crisis takes to chattering, During Hard Braking that is.. .. ..

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

Could it be that with the updated suspension and better braking system you are more confident to push the limits causing the tyre to brake traction?

Nelly

Sent from my HTC One using Tapatalk

08, stock brakes. I propose we start a fund to get Final Impact a video camera! :cheer::cheer: :thumbup: :justkidding:

Hey, I'm not trying to do a "Stoppie" here, just slow the damn thing down. Its not insane neck snap braking and certainly not locking the wheel - I promise you that. I go fast, but its a very smooth fast. I pull hard out of the corners, brake just enough going into the corners to hit my marks - although sometimes through the corner entry. My style this year has not changed. If you could all see the narrow, rough roads we travel, it may help here... But something has changed I just need to figure out what it is.

 

[darius]

Re: Crisis takes to chattering, brakes that is.. .. ..

I go fast..

That must be it. Now slow down and stop using the front brake so much.

 

[aclayonb]

Re: Crisis takes to chattering, brakes that is.. .. ..

Please tell me that stock brakes isn't "brakes from 2008"? As in, no rebuild or clean out in almost 6 years?

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

With it occurring most of the time braking downhill, especially hard braking , as you mentioned, the forks are compressing more than on flat ground.

I would strongly look at a slightly longer spring spacers (or if there's an adjustment-extend it) to keep the forks from dipping quite so far.

I don't know why they would chatter unless the front tire is "skipping" on the road, perhaps too much dampening, not allowing the forks / wheel to extend back out.

All the above is after ruling out crap on the disc's / pads.

Just a thought..

As a test, I'm sure that changing the preload/sag would change this in someway. However, I would be putting it back to the sag its at now. 31mm IIRC. PS - no, tire is not skipping and frankly, its not the brakes that are chattering - its me! Picture a wood pecker hammering on the forks.

As it stands now I need to check the sag before I tear it down for fresh oil just to see if it changed any.

I have -
New Fork oil
New brake pads << not sure I'll install them. We'll see how much materials is left.
New brake fluid

I'll throw a dial indicator on the rotors just so everyone can see the run-out if any. Although the magnetic base would stick better if I had steal fork housings.... lol I've been working lots of hours and w/the weather in the teens and twenties, working on Crisis has not been a priority. Hopefully sometime around Christmas I can get a few things done.

Off topic ToDo List:
- Dump radiator fluid / flush, refill
- Install 5 degree advance pickup wheel. Waiting for gasket
- Build a new tail tidy, add brace back lost in TB exhaust install
- Add new LED license plate light
- Make some side marker lights...

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

2014-01-04 Inspection:
First off, best of plans did not come into play - i.e. change one thing at a time and determine the primary root cause. So, this is more of a restore the baseline.

I measured the SAG and found the R6 forks had settled from 31mm to 36mm. The spring free length did drop a mm from 252mm to 251mm (recorded in previous thread below).

I didn't measure the oil depth in the fork before dumping but they weren't leaking so I just dumped them and refilled them with Yamaha 7.5 wt. A NEW change from 10Wt to 7.5 wt.at a depth set to 106mm. Note: Old oil looked pretty clean, not grey, no metallic bits. A 2 year interval it is!

FROM: 2012-02 http://www.600riders.com/forum/fz6-general-discussion/36842-somethin-black.html#post461560
OIL FILL SPEC: 490mL should have come out. I got 470mL. Without the spring and spacers and washers in the way and with the tube collapsed it should measure from the top 106 mm (4.17 in).
FILL Height to level: a 1 pint bottle or 473mL

Note: the coil spring winding is supposed to be wound tighter at the top. Nada - equal throughout the entire coil. This is begging the question if these are/are not OEM R6 springs.
As found:
Coil Dia= 4.72mm 0.186"
Coil spacing = 9.26mm .366" between coils
Free length = 252mm spec: >244 <249 (9.81" - 9.62")
Coil count: 7coils/10cm or 17 coils not counting ground ends.

Forks were assembled, SAG returned to 31mm. New oil will likely require damping rate adjustments.

BRAKES:
Right side pad thickness all over 3mm
Left side pad inner >3mm, outer slight taper 2.5 to 3.0mm.

Caliper Pistons:
RS caliper all pistons freely move by thumb pressure.
LS caliper one piston firm but not stuck. By holding other the 3 in place by HAND, break pressure applied, piston moves for cleaning. Repeated 3 times, all pistons move with finger pressure. Although I have new pads, I did not install them.

Wheel hub, rotor visual inspection:
No obvious run out from wheel or tire. Rotor surface. Anyone familiar with hot spots, hard spots on surfaces? Its not obvious but the rotors appear to have tell-tale signs of being too hot. The only time I could see the imperfection was after wiping them with brake cleaner. It appears as circles between the drill holes. If these were meant to be resurfaced, often times the process reveals the hard spots when cutting or being ground away. I did not measure run out on rotors as I was freezing at 35F for the last few hours and put it back together. A more thorough inspection is required.

ROTORS: My Actual Rotor:
Lighting in the area the bike is sucks and I couldn't get anything to show up last night. Here is pic of the Rotor from 2013-06 when the S20 front tire went on.
View attachment 51648

Borrowed from a search for reference. Mine now have a dark blue hue closer to this.
View attachment 51650
But not as bad or pronounced as this showing the hot spots.
View attachment 51649

My take away is I might be asking a bit much of the brakes as some entry speeds require more brakes than she has to offer. Another thought is the Thicker (NEWER) pads have more mass and may have made a better heat sink extracting some of the heat from the rotors. As they thin, the temperatures climb quicker and the rotor gets hotter. SO, perhaps a different pad is in order or those new pads should be installed.

Finished the evening by bleeding the brakes:
Emptied fluid reservoir with 50cc syringe. Added new Dot 4. Bled brakes manually, tapping calipers with hardwood to displace any residual air. Tap only upwards and NOT from the sides.

I'm undecided about any ONE item as the cause. I don't believe the rotor condition is directly related to the suspension bouncing like rubber ball. So, that's where it stands right now.

I'll make an adapter for this so I can secure it at the caliper bolts. Runout and deviation of the rotors hard spots may be detectable.
View attachment 51654

 

[TownsendsFJR1300]

Re: Crisis takes to chattering, brakes that is.. .. ..

Randy, I don't know if it relates to your chatter issue but would relate to any hot (blue) spots on the rotor.

As you know, Yamaha recommends new brake seals every TWO years. I've found 4-5 years is more realistic.

If you've never changed the seals out, being your bike is now approx 5 years old, I would change them out. Just that one sticking some, will ONLY GET WORSE.. You'd be surprised at much easier the wheel will spin without the extra drag.

Just throwing out something, if that one brake caliper (one piston) is indeed sticking, causing that hot spot, I would think one caliper braking more than the other would not be good and could possibly cause your issues. Potentially warping the rotor, then the chattering occurs, especially if running hard..

If it was warmed outside, I'd ride the bike, stop with the rear brakes only and feel or measure the temps of the ft rotors. They of course, should be about the same.

IMHO, with all your done with the front end, I would replace those seals just to rule them out (I know its an R6 ft end)...

 

[Carlos840]

Re: Crisis takes to chattering, brakes that is.. .. ..

If you haven't done it yet, try cleaning the pistons with a tooth brush and some soapy water! Pump the brake a pit until they come out enough to be shiny, and then just brush the crap ring away with the brush, a little break cleaner helps to!

Before doing it i had stuck/lazy pistons, after doing it, it all works fine, and i get a lot less drag!

[ame=http://www.youtube.com/watch?v=F4CDe5ARBSI]Delboy's Garage, Winter Brake Service. - YouTube[/ame]

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

2014-01-04 Inspection:
Caliper Pistons:
RS caliper all pistons freely move by thumb pressure.
LS caliper one piston firm but not stuck. By holding other the 3 in place by HAND, brake pressure applied, piston moves for cleaning. Repeated 3 times, all pistons move with finger pressure.

DONE - All Pistons move with equal FINGER PRESSURE. All of them. Wheel exhibits no drag when spun. Push one piston a random one pops out.

I'll order some new seals as it is wise at this time in its life.

Look, its a caliper....
View attachment 51653

 

[TownsendsFJR1300]

Re: Crisis takes to chattering, brakes that is.. .. ..

If you haven't done it yet, try cleaning the pistons with a tooth brush and some soapy water! Pump the brake a pit until they come out enough to be shiny, and then just brush the crap ring away with the brush, a little break cleaner helps to!

Before doing it i had stuck/lazy pistons, after doing it, it all works fine, and i get a lot less drag!

Delboy's Garage, Winter Brake Service. - YouTube

That will indeed help however, the rubber seals harden over time and will stick again and get worse.

Before replacing my seals, I pulled them ALL APART, cleaned them SPOTLESS, used brake specific grease too on the seals (made for brake seals) for the re-installation.

Helped for about 9 months, then started dragging again...

Put new seals in, 200% better.

BTW, putting the old seals next to the new ones, I could NOT SEE or feel any difference. Once installed, the difference was extremly evident... I'm good for for at least 4 years... As a side note, I do, maybe once a month or when boarded, just take the air compressor to the calipers and blow all the dust out (inboard and outboard pads). A bunch of dust usually comes out, especially the fronts...

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

2014-01-04 Inspection:
First off, best of plans did not come into play - i.e. change one thing at a time and determine the primary root cause. So, this is more of a restore the baseline.

2014-01-25 Test Ride ~50 miles:
Great weather today but a tad chili at 45F w/the gear i had on.

Recap:
Rotors, pads, calipers cleaned. Brakes bled.
R6 forks fluid changed from 10wt to 7.5wt, sag returned to 31 mm.
Tire pressures at 34F/36.5R
Tank empty to tank Full

NO changes to Bar angle.

Brakes felt good, suspension nice and firm AND tracking the road very well. Again, very satisfied with the damping on the nose. Turn in is lovable and she is truly a joy to ride!

In short, after not riding for 3 months, I wasn't pushing it as much as required to really heat the brakes at heavy lean angles so I can't say I 100% duplicated the conditions that had previously caused the nose to beat like wood pecker but I can say the bum stretch of road (the washboard section know to cause the issue) did not induce a hint of chattering. This seems like GOOD NEWS, as there were no signs of it at all and I think it should have been enough. Time will tell.

I did velcro a wrap around the stanchion tube to get an idea of how much travel is being consumed. I measure 4.0".

By the book the R6 Forks have 120.0 mm (4.72 in) of wheel travel.
According to this: I'm using 102 mm of it. I hit one pretty fair dip and I'm guessing that consumed most of it. In short its good to know its not bottoming and there is still room for more but 0.72" IS NOT leaving much before we bounce off the road or taco a rim. The oil weight change made the forks react quicker just a tad quicker but a longer ride is needed to fine tune them again.

102 mm of travel being consumed (4.0" of 4.72")

My actual rotors:

Lastly, this may seem like nothing - but I'll through it out there. It was 37F when I filled the forks and capped the tops. Air expands with heat right. Well, as the forks work and IF THEY DON'T LEAK, they'll actually have pressure inside I suspect! Impact on this??? IDK! Maybe none.

Thats it for now.

 

[chornbe]

Re: Crisis takes to chattering, brakes that is.. .. ..

Just a thought; it could actually be a rotor over heating and rather than warping, a kind of swelling. I ran into this quite a bit on the Hyundai Excel/Pony cars back in the 80s when I was still turning a wrench for a living.

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

Over this past weekend I had the bike out and ran some of my typical places. Temps were mid 60 and I did about 150 miles. All things being equal I'd like to think I duplicated some of conditions from last year.
-> From this I'm Happy to report no repeats of Wood Pecker like pounding to the bikes nose (so far). :thumbup:

I know I said it before but here goes again:

Changed:
Fork oil from 2 year old 10 wt to 7.5 wt
Front Sag: from 36 mm to 31 mm (my springs have sagged)
Bled & flush brakes

Inspected & Cleaned:
Calipers / pads / rotors

Confirmed before each ride:
Tire pressure @ 36.5 - 37 and 33.5 - 34.5

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

***********************************

A recap of the process I use to bleed brakes:
Tip number one - buy a syringe and some soft tubing. Preferred is silicone as it can stretch to any size. Then when it comes time to do the brake flush, suck out the old fluid and dump in the new.

** NOTE: Always use Fluid from a NEW UNOPENED CONTAINER!!! **

• After filling MC, install cap/lid, pump level/pedal and hold lever down with pressure.
• Crack the bleeder and continue applying pressure to lever. When the lever bottoms, seal the bleeder.
• Repeat above steps until clean fluid is coming out.
• Do both sides (back etc).
• On the final bleed, seal the bleeder before the lever reaches bottom. This prevents air from entering the system.
• Clean everything spotless and repeat once a year when using Dot 4 fluid!

Use a syringe to remove old fluid! It's way better than pumping it through!

If you have a long hose, run it straight into a pan or bottle. Here I was in pinch and just let it fill up the syringe.

• Do not get brake fluid on anything as it eats paint and will/can dull powder coated items too.
• ** DO NOT LET THE MC reservoir go empty and suck air or your brakes will be all mushy and you'll have to start the bleeding process over!! **

Also, DOT4 fluid is MORE hygroscopic than DOT3 (it attracts moisture). As such, it should be changed annually!
***********************************

 

[darius]

Re: Crisis takes to chattering, brakes that is.. .. ..

Front Sag: from 36 mm to 31 mm (my springs have sagged)

What about the Christmas pudding factor- rider weight the same as last year? Blah

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

Front Sag: from 36 mm to 31 mm (my springs have sagged)

What about the Christmas pudding factor- rider weight the same as last year? Blah

^^ Meanie.... ^^ :spank::spank: And I voted for your BOTM picture too!

Pudding factor only applies if it jiggles! Rider reports no jiggle! :thumbup:

****************************


So, Tally is roughly 400 miles and NO repeat of the incident that started this thread. Brakes are good and I have a few Tax pennies back which I thought I might throw at Crisis.

Spiegler Performance Parts - Brake Line Kit
S-YA0194 $114 2 lines and a bolt!
S-YA0196 $175 OEM style w/a block

OR
Amazon.com: Galfer D585-2 Steel Braided Front Brake Line: Automotive
Galfer D585-2 Steel Braided Front Brake Line $90

 

[elus1ve]

Re: Crisis takes to chattering, brakes that is.. .. ..

I'm a bit late in this thread but I have had the same thing happen a few times in the last few weeks but I mostly blame it on the temperature being 0-10 deg celcius. All cases have been on a downhill and slowing down.

I also locked my rear tires more than once too on light braking.
Cold temp + dirty spring roads + skills waking up from hibernation + loosing a lot of weight = all sort of weird things, but I haven't blamed my Fz for anything yet other than making me go in the cold.

 

[FinalImpact]

Update: 2014-05-07

So, after cheating on Crisis at Yamaha demo days { http://www.600riders.com/forum/fz6-general-discussion/52780-yamaha-demo-day-fz-09-test-ride.html } I went for a 70 mile ride through all sorts of terrain. Some of that involved heavy heavy braking in switchbacks. I blame the insane Torquies of the V-Max and the thrill of the FZ-09 for leading me to this state of mind and the events leading up to this moment! Truth be known, end of last year I was pushing it bit much on the street. All in good fun and mostly pretty sane & safe, just elevated speeds if you will. So I vowed to take it down a notch and I have until tonight. Well, mostly.. .. ..

On this braking topic; I've mashed on them at speed and thought I had the issue resolved and I do believe I have but now there is some doubt as it was back tonight. Two things changed - read on if interested.

How can it be resolved and back all in the same sentence you ask? Well, in my quest to get to Demo days I slacked AND DIDN'T CHECK the TIRE PRESSURE. Guess, what, the difference of 1.5 PSI is a life or death margin. Hard to believe? I agree, it is. Its very likely there is more in play than I've solved to this date. HOWEVER; the one constant in this Woodpecker like Jack Hammering of the head is Tire Pressure.
Conditions are this:
- Drop lots of speed quickly (making heat at the pads/rotor)
- Do it repeatedly (more heat to everything)
- Add variables, i.e. washboard road surface is the "most reliable" igniter to light the fuse so to speak.
- Run with low tire pressure (33 psi).

As best I can tell running it at 34.5 PSI and this is not an issue. Let it get to 33 and push it and walla - the woodpecker is hammering! Mind you it NEVER got as bad tonight as it was last year!!! Think of a mans shaver vibration vs holding Jack hammer breaking concrete. One is noticeable and the other is deadly.
At this moment - tire pressure is really rising to the top of the stack as root cause. So I have to wonder the following:
Does the S20 just not go well with the 023?? Could the back of the bike really be playing a roll here?? I have some new brake pads I will throw on there and drop the pressure to 33 and see if heat transfer changes anything. The current pads have life but I KNOW THEY ALSO HAVE LESS MASS than a NEW set of pads, so they must heat up quicker. Point: the rotor is hotter quicker! Also, am I giving up traction to reduce the risk of dribbling the nose??? I really have to wonder. I do believe its time to write the tire manufacture and ask some candid questions.

Anyway, the chicken is gone from the 023 and that took some lean angle! :thumbup:

I'll post up after pad change at lower pressure & higher pressure. But it will take some time to bed the new pads and hear back from the makers of the beloved BattleAxe!

 

[Cali rider]

Re: Update: 2014-05-07

Big snip......

How can it be resolved and back all in the same sentence you ask? Well, in my quest to get to Demo days I slacked AND DIDN'T CHECK the TIRE PRESSURE. Guess, what, the difference of 1.5 PSI is a life or death margin. Hard to believe? I agree, it is. Its very likely there is more in play than I've solved to this date. HOWEVER; the one constant in this Woodpecker like Jack Hammering of the head is Tire Pressure.
Conditions are this:
- Drop lots of speed quickly (making heat at the pads/rotor)
- Do it repeatedly (more heat to everything)
- Add variables, i.e. washboard road surface is the "most reliable" igniter to light the fuse so to speak.
- Run with low tire pressure (33 psi).

As best I can tell running it at 34.5 PSI and this is not an issue. Let it get to 33 and push it and walla - the woodpecker is hammering! Mind you it NEVER got as bad tonight as it was last year!!! Think of a mans shaver vibration vs holding Jack hammer breaking concrete. One is noticeable and the other is deadly.
At this moment - tire pressure is really rising to the top of the stack as root cause. So I have to wonder the following:
Does the S20 just not go well with the 023?? Could the back of the bike really be playing a roll here?? I have some new brake pads I will throw on there and drop the pressure to 33 and see if heat transfer changes anything. The current pads have life but I KNOW THEY ALSO HAVE LESS MASS than a NEW set of pads, so they must heat up quicker. Point: the rotor is hotter quicker! Also, am I giving up traction to reduce the risk of dribbling the nose??? I really have to wonder. I do believe its time to write the tire manufacture and ask some candid questions. ...

Resume snip

The Botts' dots between lanes would usually set off the hammering effect for me. Without discounting your theories, I tried several brands and models of tires with corresponding experiments with pressure values and found the chatter would ALWAYS return eventually. Changed brake pads and rotors, did the R6 fork mod, etc. Never solved it. Read my post again for a checklist: http://www.600riders.com/forum/fz6-technical/46100-what-brake-pads-do-you-use.html#post502270

I still think it's an issue related to the chassis. Swingarm bearings/axle or actual frame distortion. It's really odd that it doesn't stay consistent, just like you mentioned.

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

[MENTION=681]Cali rider[/MENTION]
I didn't research all your post to find "what" tires you ran on the bike but here is what I am finding.

Of the Sport Tires Bridgestone makes, the S20 which I'm currently running is the softest ply sidewall & carcass they have released thus far. I've been speaking with a NW rep who said some bikes have this issues and its a product of the sidewall interaction with the suspension.

I saw in one of your posts you ran 023's. Was that both front and rear? These do have a stiffer carcass than the S20 I'm on now and what I'm finding is NEW, the tire only had this woodp@cker issue at speeds greater than 60 mph and as the tires looses tread off center it will hammer at speeds as low as 20 mph. Do note its the same rate of hammer, but we're at a different speed.

The rep suggested try stiffer sidewall tires and so I'm real curious what all tires you had on the bike and if you could tell the difference in rate of occurrence from a new tire to used up tire. i.e. did it get worse??

Observation: the S20 with no air in it is so pliable it feels as though one could stick their thumb right through the tread off center. Its VERY soft in the tread area.

I may go back to the 016 PRO or Maybe a T30 but thoughts go towards the 16 if I can find one.

Bridgestone Battlax Hyper Sport S20 Front Motorcycle Tire
Size: 120/70ZR-17,
Tire Construction: Radial
Load Rating: 58 (520 lbs.)
Speed Rating: W (168 mph)
Max PSI : 42
Load Range: B
Tread Plies: 2 Rayon 1 Steel
Sidewall Plies: 2 Rayon
Position: Front
Weight: 9.35 lbs.
==========================

FWIW: M-Spec tires are tires that a motorcycle manufacture will have modified from the original design to meet the needs of "their" production bike.

==========================

Time for some more reading I guess and find a new tire to try.
Edit: added S20 pic's as they near the end. And yes, the rightside is missing more tread!

 

[FinalImpact]

Re: Crisis takes to chattering, brakes that is.. .. ..

Notice the extra steel cord??
Battlax BT016 Pro Hypersport Front Motorcycle Tire
Size 120/70ZR-17
Tire Construction Radial
Load Rating 58 (520 lbs.)
Speed Rating W (168 mph)
Max PSI 42
Load Range B
Tread Plies 2 Rayon 1 Steel
Sidewall Plies 2 Rayon
Position Front
Sidewall Blackwall
Weight 9.4 lbs.