ninjette.org

Go Back   ninjette.org > 1986 - 2007 Ninja 250R > 1986 - 2007 Ninja 250R Tech Talk

Notices

Reply
 
Thread Tools
Old August 27th, 2015, 03:20 PM   #1
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
Time for a new rotor? New brake pads? Both?

As with every relationship, my bike and I have had our ups and downs. We've laughed and we've cried together but lately we've been having a lot of relationship issues. She has become very needy and wants me to spend more time working on her and spending money on her. I just don't feel the same satisfaction as I did before she changed. However, I still deeply care for her and want to help her through this tough time so we can both be happily together again on the open road.

I'm sorry to ask for help again, but I want someone's opinion who is better versed at this than I am. When I'm on the bike and it's moving, I hear a grinding noise. The noise is also there when the bike is on the center stand and I spin the rear wheel. My brakes also seem to pulsate. From what I have read online, this makes me think either my rotor is bad or I need new brake pads. Under further review, the look like this. The lines are what worry me, but I'm not sure if that's a common thing with motorcycles. I checked the brake pads and they are definitely below the recommended 1mm Kawisaki suggests. Could this noise be coming from just needing new pads?

I don't exactly have a whole lot of money to keep throwing at her but I think this is the last issue before I can finally ride her again. I'm willing to do whatever it takes.

Thanks again, Ninjette, for being such an awesome community and sorry to be so bothersome!
Attached Images
File Type: jpg 20150827_142659.jpg (87.6 KB, 26 views)
Mocha Man is offline   Reply With Quote




Old August 27th, 2015, 03:32 PM   #2
csmith12
The Corner Whisperer
 
csmith12's Avatar
 
Name: Chris (aka Reactor)
Location: Northern KY
Join Date: May 2011

Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track)

Posts: Too much.
MOTY 2015, MOTM - Nov '12, Nov '13
No bother Nolan, don't sweat it.

The rotor has some wear no doubt but don't look super terrible. At the very least you need some pads to stop the grinding. Before you install them though, you need to do a few things.

1. check the straightness of the rotor - warped = replace
2. mic the rotor for thickness - too thin - replace
3. deglaze/clean the rotor so the new pads bed in well

Might as well clean up the caliper real well since you have it off. Slides and pistons at the very least and check them seals.
csmith12 is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old August 27th, 2015, 03:40 PM   #3
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
Quote:
Originally Posted by csmith12 View Post
No bother Nolan, don't sweat it.

The rotor has some wear no doubt but don't look super terrible. At the very least you need some pads to stop the grinding. Before you install them though, you need to do a few things.

1. check the straightness of the rotor - warped = replace
2. mic the rotor for thickness - too thin - replace
3. deglaze/clean the rotor so the new pads bed in well

Might as well clean up the caliper real well since you have it off. Slides and pistons at the very least and check them seals.
I checked for straightness before I posted and it didn't look warped to me, but it was also somewhat difficult to tell with the brake pad still on. I only have three more questions...

1. How thick should the rotor be?
2. What do I clean the rotor with?
3. I was planning on cleaning the caliper after removing it, but what do I clean it with? Just water?

Sorry again for all the noob questions and thanks for the help!
Mocha Man is offline   Reply With Quote


Old August 27th, 2015, 03:43 PM   #4
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
I tried to get a picture of the rotor thickness earlier as well, but I wasn't sure if it'd be all that useful in the diagnosis haha. I took it with my phone and Ninjette orients the pictures to a landscape mode by default.
Attached Images
File Type: jpg 20150827_142711.jpg (89.7 KB, 15 views)
Mocha Man is offline   Reply With Quote


Old August 27th, 2015, 04:00 PM   #5
csmith12
The Corner Whisperer
 
csmith12's Avatar
 
Name: Chris (aka Reactor)
Location: Northern KY
Join Date: May 2011

Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track)

Posts: Too much.
MOTY 2015, MOTM - Nov '12, Nov '13
Quote:
Originally Posted by Mocha Man View Post
I checked for straightness before I posted and it didn't look warped to me, but it was also somewhat difficult to tell with the brake pad still on. I only have three more questions...

1. How thick should the rotor be?
2. What do I clean the rotor with?
3. I was planning on cleaning the caliper after removing it, but what do I clean it with? Just water?

Sorry again for all the noob questions and thanks for the help!
I use a brillo pad (steel wool) and acetone/brake cleaner to clean rotors and the service limit on thickness of the rear rotor is 5mm. Brake cleaner and steel wool on the caliper too, just don't rough up the seals.
csmith12 is offline   Reply With Quote


Old August 27th, 2015, 04:16 PM   #6
Alex
ninjette.org dude
 
Alex's Avatar
 
Name: 1 guess :-)
Location: SF Bay Area
Join Date: Jun 2008

Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE, '15 CRF110F, '13 TT-R50E

Posts: Too much.
Blog Entries: 7
The grinding can definitely just be coming from the pads, do you have any close-up pictures of those? If in fact the pads are worn to the point they are making a grinding noise, then it is important to change them out before riding any more, as any further use is much more likely to damage the rotor and provoke a more expensive fix.
__________________________________________________
Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org

ninjette.org Terms of Service

Shopping for motorcycle parts or equipment? Come here first.

The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)
Alex is offline   Reply With Quote


Old August 27th, 2015, 05:33 PM   #7
dcj13
Participant
 
dcj13's Avatar
 
Name: Dave
Location: South of Seattle
Join Date: Oct 2012

Motorcycle(s): '94 K75 std

Posts: Too much.
MOTM - Aug '15
Whereabouts in NW Washington are you?
Perhaps we could measure thickness and wobble with my micrometer and dial indicator.

Gosh, I love metrics...
dcj13 is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old August 27th, 2015, 06:26 PM   #8
Ghostt
in your machine
 
Ghostt's Avatar
 
Name: Scott
Location: Summer Shade, Ky.
Join Date: Oct 2014

Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN"

Posts: A lot.
Blog Entries: 25
MOTM - Jun '17, May '16, Mar '15
Here's a few write-ups for your information,

For those of you whom are scratching their heads, here you go,*


Front Caliper Service (also rear as well)

Many folks have posted here with a Varity of front brake problems.

*Many of which are attributable to the lack of proper maintenance.

*Here’s how you can always have a brake like when your bike was new.

A short list of the problems and the causes.

Soft lever or lever goes to the bar.

The usual cause is the pistons are pushed too far back into the caliper by a flexing a warped, coned, disc.

*Using up too much piston travel before the disc is pinched.

Juddering in sync with wheel rotation.

The disc is worn, and its thickness varies. *This causes the caliper to “sink” into the thin part and when the thick part comes around, it gets wedged into a smaller space causing a tightening of the brake. Then the tight spot passes through and it like the brake is released. Then repeat, repeat.

Cupped, coned, or warped disc.

Unfortunately this is a common problem with EX’s the cause is the disc is stretched in the center due to being rigidly bolted to the wheel. *The huge force of braking is transmitted to the wheel through the webbed center of the disc which gets stretched and becomes larger than the space it occupies in the center of the disc. This causes the center to push to the side trying to find room for itself.

*Resulting is a cone shaped disc.

Soft lever 2

The caliper has pistons only on one side, so as the pads wear the caliper must shift sideways apply even pressure on both sides of the disc.

*To allow this the caliper floats on two pins. *If these pins get dry (no grease) dirty or bent. The caliper won’t center itself and bends the disc to wherever it is.

This take up lever travel and when released pushes the pistons further back than necessary.

*If not fixed will eventually destroy the disc (warp it).


Ok how to prevent all of the above.

When new pad time comes around, resist the temptation to just pop in new one and go.

*Every time you must do these things.

Remove caliper disassemble and clean it.

Clean and re grease the sliding pins.

Polish the caliper pistons to remove dirt. If you just push the pistons back into the caliper leaks will result. Or binding.

Tools required:
12 mm socket
8mm open end wrench
3” or bigger C clamp
a supply of new bake fluid.
wire brush and or steel wool.

Remove the caliper from the fork leg but leave the brake line on.

Remove the old pads and the mounting frame (the sliding pins)

Remove the cover from the Master Cylinder on the Handel bar.

Attach the C clamp to one of the pistons but don’t squeeze it. *Pump the lever on the bar slowly to push out the other piston almost all the way. *Put the C clamp on that piston and push out the other one.

Remove both pistons by hand.

Remove all the rubber part from the caliper, the seals are in the grooves in the caliper and dull pointed thingy will get them out easy.

Disconnect the caliper from the brake line.

Soak all the rubber parts in new clean brake fluid * ONLY!!!!! * Rub them with you fingers till as clean as new.

The caliper can be cleaned with a wire brush or even a Moto tool for the internal grooves, NOW’s the time to paint it if you wish.

Polish the pistons till they are smooth and shinny. They are chrome plated. If any of the plating is chipped or damaged below the dust cap groove. *Replace it.

The master cylinder is the subject of another write up and we’ll assume it in good working order here.

If you suspect your disc is bad, your bets bet is to replace it with an after market one fro EBC or Galpher.

*Don’t remove the disc unless you intend to replace it. *It will assume a new shape if it is * stressed and will not be flat again. You can try to check its condition by placing a straight edge across the face of the pad swept area looking for any distortion.

Re assembly

Take the nice clean rubber seals and install them into the caliper then the Dust covers.
Wet all the rubber with new clean brake fluid and partially fill the caliper with new fluid.

Push the pistons though the dust seals and into the caliper body until the dust covers snap into the grooves.

Fill the MC with new fluid and pump the lever while holding the Line above the MC till clean fluid flows.

Connect the line to the caliper while holding it above the MC.

Pump the lever with the bleeder valve open till fluid flow from the bleeder.

*Hold the caliper so that the bleeder is the highest point.

Close the bleeder and pump more fluid into the caliper but don’t push the pistons all the way out.

Then squeeze the pistons all the way back in and install the new pads.

Re grease the slider pins and assemble the dust seals and re mount the caliper on the forks but leave the bolts loose.

Now clamp the caliper to the disc with the brake lever.

Look at the space between the fork lugs and the caliper, clamp and release a few times as you tighten the bolts by hand. It one lug touches much before the other the odds are you mounting bracket is bent. You can straighten it.

*After you get it the best you can. Some shim washers made from alum can stock can be fitted to the loose side.*

** *What we are doing here is trying to minimize the bedd in time and gets the best pad life.


Ok with everything tight you should be through, Notice we don’t need to bleed the brakes, but if you screwed up in any of the above steps, you might do that here.

Be careful to Bedd in the new pads gently.

*Too much pressure too soon will burn the pad material as only a small area will be gripping at first. You also won’t have full braking power till the pads are fully familiar with the disc


When it comes to safety items like brakes, when in doubt, throw them out, it's your safety in your hands, and is cheaper than a visit to the ER.

Buy quality pads,I personally recommend EBC brand either the HH, or the Extreme HH.

EBC full floating rotor, and if you got any $$ left over replace the OEM rubber line with a stainless steel braided brake line, cheaper than replacing them with OEM.

On my 500 I have Spiegler line

http://www.spieglerusa.com/brakes/cy...line-kits.html

On my Ninja 250 i went with Venhill

http://www.venhillusa.com/products.html

With all that, it will stop on a dime, and leave you nine cents in change.

look here http://ebcbrakes.com/products/motorcycle/

And also read this, http://www.ex-500.com/wiki/index.php...otors_and_Pads

That should answer any questions you might have.
__________________________________________________
violente et ignorantia

ZX-2R BLOG
Twitter and Instagram = Ghostt_Scott
I'm not here to change your mind, just to inform.
Ghostt is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old August 27th, 2015, 07:37 PM   #9
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
Quote:
Originally Posted by dcj13 View Post
Whereabouts in NW Washington are you?
Perhaps we could measure thickness and wobble with my micrometer and dial indicator.

Gosh, I love metrics...
I'm very far NW, like a 20 minute drive to Canada haha If you could somehow get your bike allllll the way up here then I'd be totally DTMTW (down to measure thickness and wobble) . I definitely don't expect you to make that trip though! Lol
Mocha Man is offline   Reply With Quote


Old August 27th, 2015, 07:41 PM   #10
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
@Ghostt As Jack Black would say in School of Rock, "You're the cat's pajama's, man. You're the bee's knees."

Seriously though, thank you. That was really helpful and I will probably post an update once I get everything figured out!
Mocha Man is offline   Reply With Quote


Old August 27th, 2015, 07:44 PM   #11
Ghostt
in your machine
 
Ghostt's Avatar
 
Name: Scott
Location: Summer Shade, Ky.
Join Date: Oct 2014

Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN"

Posts: A lot.
Blog Entries: 25
MOTM - Jun '17, May '16, Mar '15
Quote:
Originally Posted by Mocha Man View Post
@Ghostt As Jack Black would say in School of Rock, "You're the cat's pajama's, man. You're the bee's knees."

Seriously though, thank you. That was really helpful and I will probably post an update once I get everything figured out!
Between those two, if you follow them, your brakes will be better than new.
__________________________________________________
violente et ignorantia

ZX-2R BLOG
Twitter and Instagram = Ghostt_Scott
I'm not here to change your mind, just to inform.
Ghostt is offline   Reply With Quote


Old August 27th, 2015, 07:48 PM   #12
MrAtom
.
 
Name: .
Location: .
Join Date: Aug 2014

Motorcycle(s): .

Posts: A lot.
MOTM - July '15
New pads for sure. Make sure to clean up them calipers good while you're in there. My rotor looks about the same and there's no issues. It's a little scary doing brakes at first but it's not so bad once you figure it all out. Do 'em one at a time with a ride inbetween so if you do manage to muck it up you have at least one functioning brake.

The only problem I recall while changing the brakes is getting the pistons to move back down. I didn't realize it'd take that much force and I'm not a very strong guy. I thought they might've been seized up or something.

http://faq.ninja250.org/wiki/How_do_..._brake_pads%3F
MrAtom is offline   Reply With Quote


Old August 27th, 2015, 09:15 PM   #13
dcj13
Participant
 
dcj13's Avatar
 
Name: Dave
Location: South of Seattle
Join Date: Oct 2012

Motorcycle(s): '94 K75 std

Posts: Too much.
MOTM - Aug '15
Quote:
Originally Posted by Mocha Man View Post
I'm very far NW, like a 20 minute drive to Canada haha If you could somehow get your bike allllll the way up here then I'd be totally DTMTW (down to measure thickness and wobble) . I definitely don't expect you to make that trip though! Lol
So Whatcom County , then... Obviously not the peninsula.
dcj13 is offline   Reply With Quote


Old August 27th, 2015, 10:50 PM   #14
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
Quote:
Originally Posted by dcj13 View Post
So Whatcom County , then... Obviously not the peninsula.
Yep, Whatcom.
Mocha Man is offline   Reply With Quote


Old September 8th, 2015, 11:43 AM   #15
Mocha Man
Blue Shell magnet
 
Mocha Man's Avatar
 
Name: Nolan
Location: Northwest Washington
Join Date: Aug 2011

Motorcycle(s): 1997 Ninja 250

Posts: 816
Update

Ordered some new pads from my local parts store. I took the bike out for just a couple minutes to see if I could find any other issues with it. It gets extremely hot to the point of almost burning after just a few minutes. I checked my coolant and everything seemed fine and there is no visible dirt in the filter on the bottom cowling (sorry, I'm not sure what the name of it is). I did notice, however, that when I was at a stop there was some sort of liquid dripping off the center stand on the right hand side of the bike. I checked my hoses to make sure they were all connected but I found this one that had a metal clip on it. From searching around online, it appears to the airbox drain hose (I'm a master detective, I know). However, http://faq.ninja250.org/wiki/Oil_Cha...n_hose_service says that there's supposed to be a drain plug at the bottom of the hose. There's definitely not anything there, though. Could this be an issue?
Attached Images
File Type: jpg 20150906_104635.jpg (141.8 KB, 11 views)
Mocha Man is offline   Reply With Quote


Old September 11th, 2015, 08:37 AM   #16
agentbad
ninjette.org sage
 
agentbad's Avatar
 
Name: bob
Location: Earf
Join Date: Apr 2013

Motorcycle(s): 2005 Ninja 250, 2006 SV650N

Posts: 642
When you measure rotor thickness measure on the contact patch where the brakes actually touch the rotor. If you're having trouble getting a good reading use a nickel on both sides of the measuring device then subtract their thickness.
agentbad is offline   Reply With Quote


Old September 11th, 2015, 08:50 AM   #17
Ghostt
in your machine
 
Ghostt's Avatar
 
Name: Scott
Location: Summer Shade, Ky.
Join Date: Oct 2014

Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN"

Posts: A lot.
Blog Entries: 25
MOTM - Jun '17, May '16, Mar '15
IMHO when I'd comes to braking system, the old saying When in doubt, throw it out. comes to mind.

One must remember that almost all the braking power is thanks to the single front rotor system. So with that in mind, I take Absolutely no chances!!! Better to spend the now, than a trip to the ER, damaged bike, or worse.

This is why I strongly recommend serving the calipers ever time you change pads, and flush and fill with new brake fluid(DOT 5.1), quality parts, NO CHEAP CRAP!! and bedding the pads properly.

Both my current bikes will stop on a dime, and leave you nine cents change, every time.

Yes it take extra time and money, but my safety is worth it in the long run.
__________________________________________________
violente et ignorantia

ZX-2R BLOG
Twitter and Instagram = Ghostt_Scott
I'm not here to change your mind, just to inform.
Ghostt is offline   Reply With Quote


Old September 25th, 2015, 02:53 AM   #18
f0r54ken
ninjette.org member
 
Name: Ash
Location: Las Vegas
Join Date: Sep 2015

Motorcycle(s): Kawasaki ninja ex250 2007

Posts: 85
Hey So I have a couple of bonus things from my ninja experiences so far. Very close to yours actually. Starting with that grind. I'm not sure how long you've had this or who did the last chain adjustment. But You should look at your axle bolts on your backtire. Right above them will be Little Distance markers; about 8 I think. Take a look at both sides real close and make sure they are both landing at the same markers.

if they aren't you'll need to loosen the axel with a breaker bar and a ...I think 24ml socket? Don't use a monkey wrench or you'll ruin the nut. Then Loosen the adjuster nuts holding the adjuster bolts in place. With those more loose you can use the bolts to correct the distance making your tire perfectly straight. Which would hopefully (with your new pads) run forward without grinding.

As for that coolant. I didn't see enough Green in that photo Are you using a 50/50 mixture or just water? Maybe someone else filled it for you. Either way I would flush it with the drain bolt. It's somewhere near the bottom left side of the bike (follow that big radiator tube.) and refill it with fresh 50/50 coolant. Don't forget about the reservoir tank hidden at the left side (butt side) panel. That will need to be filled too. Make sure you watch a video on how to do this, There's some whoopla about Running the bike a little first.

overheating? This can be a REALLY Crappy problem. And the most common one I've found reading...and experiencing. IS that damned thermometer bolted into the back left of the radiator malfunctioning. overheating means one of Four things to me.

You're short on oil
You're short on radiator fluid
You're thermometer is malfunctioning and your fan isn't turning on. (Likely)
Your idle is too high and Even with the fan the bike cannot compensate.

So check your fluids. and make sure your idle is less than 2200rpm at driving temp (there is a knob at the bottom left attached to the carb sticking out 4 inches.)
If you do this and your temperature is still escalating close to red Then park and shut your bike off completely. listen immediately for the fan. That temperature switch is Always live. Meaning even with the bike off and the key out if that engine is hot it's going to run the fan. SO if your fan is not running at that moment then that thermo switch is bad.

You can get another for 70 dollars. But personally I Just built a bypass toggle switch and turn it on whenever I come to stops or have been riding for 20+ minutes. Sorry for the wall of text. I Don't like being ambiguous.
f0r54ken is offline   Reply With Quote


Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
Cannot Get Pads Aligned with Rotor fencingdude101 1986 - 2007 Ninja 250R Tech Talk 13 June 18th, 2014 07:12 PM
Front brake pads/rotor scraping WAGESLAVEesc 1986 - 2007 Ninja 250R Tech Talk 8 June 3rd, 2014 06:13 PM
Cant find brake bolt connecting brake pads. Trubin General Motorcycling Discussion 6 June 3rd, 2014 05:35 PM
Replacing Ninja 300 brake pads time lapse rojoracing53 Videos 4 August 4th, 2013 10:20 PM
Replacing brake pads and brake fluid Bones85 2008 - 2012 Ninja 250R Tech Talk 4 April 28th, 2013 06:25 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Motorcycle Safety Foundation

All times are GMT -7. The time now is 01:26 PM.


Website uptime monitoring Host-tracker.com
Powered by vBulletin®
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.
Except where otherwise noted, all site contents are © Copyright 2022 ninjette.org, All rights reserved.