Ok folks, I'm back with more issues. My roommate recently dropped my ninjette and I'm in the process of getting back on the road. After he dropped it I walked it back to the house and that was the first time i noticed the noise. It's coming from the front end somewhere and it's a sort of clunk at a certain spot in every wheel rotation.
I changed the front wheel bearings and it still makes that noise. There's no pulsing in the front brake and it seems to ride fine. I only hear the noise when going slowly but I can feel it through the bars. I though it may be the forks but that doesn't explain the rotation thing. I've done a lot of searching and am on the verge of taking it to a shop. Any ideas?
Also, my front sprocket seems to be making a ticking/whirring sound when I ride. I changed them not too long ago but everything seemed good to go. I feel like this bike is 30 years old with all this ridiculousness going on!
Any help with either issue would be greatly appreciated.
Thanks

No one has experienced this, huh? I rode to and from work today and it seems to be getting a bit work. I'm not sure if it could be that the front brake rotor is warped. Now when I roll the bike it seems more prevalent than before. The noise always seems to happen at the same spot in the rotation. I think I'll have a mechanic diagnose it for me but I'm still hoping for some feedback from you guys.

...........but I'm still hoping for some feedback from you guys.

Could it be the coupling for the speedometer cable?

http://faq.ninja250.org/wiki/Reinstalling_the_front_wheel

Normally, the problem is in the last thing that one touches............and you have removed and re-installed your wheel for the bearings' change out.

Hmmm, it could be possible. It started making the noise before I changed the bearings out though, just after the drop. Riding today I did notice some pulsing from the front on my way to work. It's only noticeable at under 10 mph. I'm now worried that it's the brake rotor. I'd rather not spend $300 like that.

use a dial indicator or a screwdriver mounted to the fork leg to check runout on the disc. If you feel vibrations from the front though it is more than likely not the rotor but something in the wheel. I would pull the wheel feel the bearings for smoothness and check the speedo cable assembly. From there, you could check your steering bearings but that would be an outside chance of being the issue.

Hey guys, I hate to revive an old topic but this issue is happening again for me. I replaced the brake disc which solved it at first. The front brake feels great but at low speed I can hear something clunking. When I had the front wheel off I pulled the caliper pistons and cleaned/lubed everything. I did notice the pad side of the pistons had some gunk that I couldn't get off. I'm thinking maybe that gunk is causing the pistons to not return all the way. There isn't an abnormal feel to the front brake, just the noise.

I replaced the wheel bearings about a year ago (maybe 10,000 mi.). I need to get a front stand to pull the caliper apart again. Is this a major hazard? I prolly won't be able to get a stand until next week. I think I may order some new pistons just to be safe. Any thoughts or suggestions would be appreciated.

A few things to consider and check.

First is proper fork alignment, then did you service the calipers and sliders?

How-to on forks,

It often happens that a little bump (or a large one) knocks the front fork out of alignment. This can often be noticed by a off center fender or odd handling. Here's how to straighten them.

Tools required: Wrenches to loosen the triple clamp pinch bolts and the front Axel bolts.
a Flat piece of metal or glass about 3 inches wide and long enough to span the forks.

First check if you need to do this. Lay the metal plate across the bar chrome part of the fork tubes, and rock it across corner like a chair with a short leg. If it rocks your forks are Tweaked. If it lays flat without much movement (less than a 1/16") your done.

OK the forks are Tweaked.

With the bike on the center stand and the front wheel propped off the ground. Loosen all
the Triple clam pinch bolts, the top center cap nut. and the Axel and the Axel pinch bolts. Don't remove any of them just get them loose.

Check if your fork tube are bent by twisting them in the triples. they should turn freely. if they move a little then bind they might be bent.

Now rock the tubes as above, Hold the front wheel with your knees and twist the bars till the plate Don't rock.

Now gradually tighten all the bolts a little at a time as you keep checking the "Rocker" till all are properly torqued.

Your done, your front end will love you for it.


Secondly, caliper how-to guide

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

Divide and conquer!

Push down really hard on your bars to bounce them up and down? Clunk? Check if it's just bottoming out the forks (seals leaking) or the stem nut needs tightened.
Lift the front wheel, spin it by hand. Clunk, rubbing, grinding? Bearings, rotor, caliper, speedo.
Spin front wheel by hand again, get it going pretty fast. Pull the front brake quickly. Cluck? Caliper bolts/pistons, pads.

Thanks for the quick replies, folks! I'll check those things. I did service the caliper pistons and sliders although I didn't change the seals. The fork alignment thing is interesting. I'll post back with any findings.

Thanks for the quick replies, folks! I'll check those things. I did service the caliper pistons and sliders although I didn't change the seals. The fork alignment thing is interesting. I'll post back with any findings.

Chris made some good points as well. I'm not familiar with NewGen does it have a center stand?

Chris made some good points as well. I'm not familiar with NewGen does it have a center stand?

Nope

Nope

Awesome, thanks Kawasaki

If your working inside, hopefully you have exposed beams, just sling the front-end up if possible.

If you had center stand it would just be added some ballast to the rear of the bike.

Some other things to consider,

Abnormal frame or suspension noise

Front end noise
Low fluid level or improper viscosity in forks. Can sounds like spurting and is usually coupled with irregular fork action.
Spring weak or broken. Makes a clicking or scraping sound. Fork oil will have lots of metal in it.
Steering head bearing loose or damaged. Clicks when braking.
Fork clamps loose
Fork tube bent. High probability if the bike has been dropped.
Axle or clamp bolt loose.


Handlebars hard to turn

Front tire pressure low
Steering stem bearing adjuster nut too tight
Bearings damaged. You can feel roughness as you turn the bars side to side.
Races dented or worn out. Denting can occur from dropping the bike or impact with an immovable object or a hole
Steering stem lubrication inadequate. Repack bearings
Steering stem bent. Can happen from dropping the bike or from hitting a curb or hole. Do not try to straighten the stem.

Aaaaaaha!



http://i636.photobucket.com/albums/uu84/santadog79/photo.jpg (http://s636.photobucket.com/user/santadog79/media/photo.jpg.html)



Bad fork seal. The left side is good, but I'm assuming I should just do both. I've never done it before. Is it tough to do, what will I need as far as replacement parts/seals?

Here's a couple of how-to guides, read these, any questions feel free to ask.

http://www.ex-500.com/wiki/index.php?title=Fork_Maintenance

http://faq.ninja250.org/wiki/How_do_I_replace_the_fork_seals%3F

Also a good time to any any modifications to the forks, either springs, cutting or new ones, changing fork oil weight, etc..... It all depends on your budget.

https://www.ninjette.org/forums/showthread.php?t=186192

https://www.ninjette.org/forums/showthread.php?t=222763

Here's a couple of how-to guides, read these, any questions feel free to ask.

http://www.ex-500.com/wiki/index.php?title=Fork_Maintenance

http://faq.ninja250.org/wiki/How_do_I_replace_the_fork_seals%3F

Thanks!

Also, I wont be able to do this for at least a few days and all I have to get around on is the bike. Could this potentially be dangerous to keep riding?

Thanks!

Also, I wont be able to do this for at least a few days and all I have to get around on is the bike. Could this potentially be dangerous to keep riding?

Although not advised, just be aware of the different handling which this causes, no twisties for you til you get it fixed.

Everyday commuting you'll be fine.

Avoid speedbumps and potholes or you could also be replacing part 44065 at the bottom of the fork tube.

:whathesaid:

http://faq.ninja250.org/images/b/b5/FRONT_FORK.png

Ok, nice. Now I just need to order the seals and away I go. I was reading on Ninjette that the '88-'07 are a different diameter than the '08-'12. I've seen a few kits listing '88-'12 for compatibility.

Ok, nice. Now I just need to order the seals and away I go. I was reading on Ninjette that the '88-'07 are a different diameter than the '08-'12. I've seen a few kits listing '88-'12 for compatibility.

As far as I'm aware of the NewGen has a larger diameter, as discussed in other threads, PreGen has a 1mm smaller diameter.

Different part #s as well

PreGen: http://www.partzilla.com/parts/search/Kawasaki/Motorcycle/1998/EX250-F12+Ninja+250R/FRONT+FORK/parts.html

NewGen: http://www.partzilla.com/parts/search/Kawasaki/Motorcycle/2009/EX250J9F+Ninja+250R/FRONT+FORK/parts.html

Here this should clear things up, part # 56-123 is what you want, according to All Balls website

http://www.allballsracing.com/ymmsearch/index/searchfromhome/

Fork seals are easy peasy. It looks daunting at first but once you have it disassembled it'll make sense. First times are always long but you'll have a better understanding of the dynamics.