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How are your head bearings doing?

  • Head bearings OK. Under 5,000 miles on odometer

    Votes: 42 34.4%
  • Head bearings OK. 5,000 – 10,000 miles on odometer

    Votes: 30 24.6%
  • Head bearings OK. 10,000 – 20,000 miles on odometer

    Votes: 13 10.7%
  • Head bearings OK. 20,000 – 30,000 miles on odometer

    Votes: 2 1.6%
  • Head bearings OK. 30,000+ miles on odometer

    Votes: 5 4.1%
  • Head bearings FAILED. Under 5,000 miles on odometer

    Votes: 14 11.5%
  • Head bearings FAILED. 5,000 – 10,000 miles on odometer

    Votes: 10 8.2%
  • Head bearings FAILED. 10,000 – 20,000 miles on odometer

    Votes: 4 3.3%
  • Head bearings FAILED. 20,000 – 30,000 miles on odometer

    Votes: 1 0.8%
  • Head bearings FAILED. 30,000+ miles on odometer

    Votes: 1 0.8%

  • Total voters
    122
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Could be tires or wheel alignment as well but before spending any money, check your bearing. If you're not sure how, watch this video from Ari Henning on youtube. It won't let me post a link because I'm new to the forum.

search "How To Check And Adjust Your Motorcycle Steering Head Bearings | MC GARAGE - Motorcyclist Magazine".


Yeah new tires and weights fixed this problem a long time ago thank god. Thanks though!


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^^
No sweat! That guy also has lots of short videos on general maintenance. Good stuff to watch and will give you an idea of what to look for when common problems arise.
 

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Just changed my vote as I just developed the steering wobble today as I passed 6,000 miles. What is odd is that I felt like something was off when steering at low speed over the last 5-600 miles or so. I was not getting any wobble when I'd let go of the bars and figured it was just me but then today I got quite a bit of back and forth from 55 mph down to 40 or so. Well, looks like I've got a great project to start my winter!
 

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Just changed my vote as I just developed the steering wobble today as I passed 6,000 miles. What is odd is that I felt like something was off when steering at low speed over the last 5-600 miles or so. I was not getting any wobble when I'd let go of the bars and figured it was just me but then today I got quite a bit of back and forth from 55 mph down to 40 or so. Well, looks like I've got a great project to start my winter!
How can you be sure enough that it is a head bearing issue to change your vote?Is it possible it could be a tire or rim balance issue?
 

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How can you be sure enough that it is a head bearing issue to change your vote?Is it possible it could be a tire or rim balance issue?
I suppose it could be a tire issue but the fact that my low speed steering felt weird just prior to the wobble leads me to think it is likely the bearing. Rims have the same weights on them that have always been there. I plan on lifting the front to test side to side movement to be sure and, if I'm wrong, I can always change my vote back, right?
 

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How can you be sure enough that it is a head bearing issue to change your vote?Is it possible it could be a tire or rim balance issue?
Head shake is never "one issue". I had this text written up before, I suppose I'll post now:

I'm writing all this clearly and extensively so I can refer people back to this post easily. This isn't a How-to, it's a Why.

Most people are indeed going to suggest tapered steering head bearings to solve head shake, and that's because for most people it works. It worked for me. Do a search and don't listen to just one person in a thread.

People need to recognize all the interacting factors that cause this. Bearing wear and slop, head nut torque (and that's the nut under the top triple clamp), uneven side to side tire wear (cupping), size of the contact patch, frame flex and fork flex. If a few conditions line up just right, the head shake appears. Change one thing in this equation and the end result might not = head shake. While sometimes putting new tires on might hide the head shake for a few people, it's important to note that the variable with the biggest effect is the bearings.

Note that tire balance does not play a factor in this. It's something you feel in the seat and bars, and it may be bad enough to affect traction in braking and cornering, but since that balance happens in the vertical plane it's not a factor in head shake. Out of balance wheels are bad news, but don't blame head shake on it. The Ninja front wheel is not wide enough to have a lateral balancing issue that a dynamic balance would fix.

An improperly seated bead could however contribute to head shake. Inspect the tire near the rim all the way around on both sides. There is a little molded ridge in the sidewall and it should be the same distance from the rim everywhere. If not, break the bead, lube the rim and reseat it.

Make no mistake, the head bearings have the largest effect on this. Here's why: The non-enclosed ball bearings wear faster because the contact area of the balls on the races is very small. Lower contact area equals higher wear and more sensitivity to lower grade balls and races. The friction difference between balls and tapered rollers has little to do with it. Tapered rollers have much more contact area with the races, resist wear better, and support a higher torque of the head nut. Not to mention that the All Balls set is much higher grade than the crap Kawasaki is using to save $5. There's a reason most of the high performance supersports use quality bearings from the factory. They aren't cutting corners to save money.

The part that sucks is that replacing head bearings is a pain in the ass. Kinda hard to DIY in your garage. And if you take it to a mechanic to do it, it's going to be expensive. That is even if you find a mechanic who's not an idiot and has the right set of tools to pull the old races and press the new races into the head. So the bearings don't have to be the first thing you do. Want a DIY how to, look at ninjette.org or youtube.

The first thing you should do is the cheapest and easiest: support the front end off the ground, turn the bars to both sides and if there is binding or noise the bearings are shot. Grab the front forks on both sides and push back and forth. If you hear a clunk or feel movement, that's a problem though it might not yet mean the bearings are shot, they just might be loose.

While the front end is suspended, visually inspect the front tire. Spin the tire. If you just look at it without the tire spinning, it will be harder to see cupping. If you see cups forming, particularly off the centerline, tires are the first thing you have to fix. Note that some tires affect head shake more than others. Sport touring tires that have a flatter profile in the center (and therefore a larger upright contact patch) are going to be more prone to head shake than a V shaped pure sport tire that has a smaller upright contact patch.

If the tires look good, but the forks have a little movement, then it might be time to check the stem nut torque. That's the special notched nut under the top triple clamp. It's reasonably easy to get to by removing the top triple but since it's a round nut with 4 notches, it will need a special tool. The crappy OEM bearings can support a stem nut torque of 15 ft lbs. Not to be confused with the steering stem head bolt, the one you can see on top, which is 32 ft lbs. Now if the bearings are worn, tightening the stem nut back to 15 ft lbs may temporarily solve the head shake but it will probably feel like some friction turning and the bearing life is going to be short before the head shake comes back even worse.

If the tires are good, you've checked (and tightened) the stem nut torque and 2 weeks (or 2 days) later the wobble is back, THEN you've exhausted the easy stuff and it's time for the pain in the ass tapered bearings. Cheap if you can do it yourself. If you bring it in somewhere, get a price, then ask for another price if you bring the bike in with the fairings completely removed. Most will lower the price for you then since you are saving the tech some time.

Note that tapered bearings can support a center torque higher than the OEM ball bearings, without damage or excessive friction. I'm not sure but I'd estimate around 25-30 ft lbs. Just don't get confused and torque the stem nut to the torque that the top nut should get, or you might wreck your bearings. As far as other possible causes, I have some speculation that Kawasaki assembly line workers are over torquing the stem nut and damaging every single one of them at the factory, causing a limited lifespan. It is Thailand assembly after all.

The benefit to installing tapered bearings isn't just stopping the head shake, the bike has a more solid and stable feel, particularly through bumpy corners. Want your mind blown? Get some good tires AND install the tapered bearings. The bike will be transformed.
The DIY home ladder method for fork removal:


Side note: Dealer/Kawasaki will not support damaged bearings under warranty, no matter how much you bitch about it, even if the bike only has a few hundred miles on it. They will say some stupid shit like "that's normal on these budget bikes". No it's not, morons. Kawasaki knows about the number of bikes with this problem is not going to pay the warranty claim. If they did it would open the flood gates to a lot of expensive work. Since it's work intensive, the dealer isn't going to do it for free, and even if you somehow manage to talk them into doing it, all they will do is put a new set of crappy OEM bearings in.
 

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Yeah new tires and weights fixed this problem a long time ago thank god. Thanks though!


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Glad to hear a new tire fixed the problem.
 

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A follow-up to my previous post - I tightened down the bearing nut just slightly as the service manual says to do it in 1/8 turn increments, at most. Test ride was interesting as the wobble was gone while decelerating from 50-40 mph but then was even more exaggerated from 40-30 mph. It was disconcerting, to say the least. A little more tightening and another test ride gave better results with the steering now tracking straight. If/when the problem reoccurs, I plan on installing the tapered bearings...
 

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I have over 20,,000 miles on my bike. I only experience a wobble if my right hand is not on the handle bars and I am decelerating. Does this mean the head bearing is going?
 

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I have over 20,,000 miles on my bike. I only experience a wobble if my right hand is not on the handle bars and I am decelerating. Does this mean the head bearing is going?
It might. It might also mean that your tire pressure is a little off, or that your tires have an odd wear pattern to them, or the front tire is out of balance, or that your brake rotor is a little warped, or that your wheel bearings are wearing, or that... or that... or that...
Wobbling alone cannot conclusively diagnose a problem. There are so many things that can cause a wobble and changing out the head bearings with tapered bearings may stop the wobble without correcting the cause (as the tapered bearings have more drag on them by design which will dampen out a wobble caused by anything).
One way to check might be to lift the front wheel off the ground by lifting from the frame and trying to move the headstock laterally (fore/aft or side/side, not turning). If there is play, you might be looking at worn bearings (though I can't say for sure how much play would be expected from serviceable OEM bearings without further research).
 

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Flew over 6 closely stacked speed bumps at around 40-50kmph and ended up in a massive tank slapper. Luckily I didn't crash, but from then onwards, the handle bars developed a slight wobble when I let go of it. This happened when I was around 3000kms.

Kawasaki service centre resolved this issue by loosening up the head bearings. The same issue started cropping up a month later, and I got it adjusted again from them. Now I'm at 6000kms and a slight wobble is still there even now. It's not that noticeable, but the factory feeling is long gone.
 

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It might. It might also mean that your tire pressure is a little off, or that your tires have an odd wear pattern to them, or the front tire is out of balance, or that your brake rotor is a little warped, or that your wheel bearings are wearing, or that... or that... or that...
Wobbling alone cannot conclusively diagnose a problem. There are so many things that can cause a wobble and changing out the head bearings with tapered bearings may stop the wobble without correcting the cause (as the tapered bearings have more drag on them by design which will dampen out a wobble caused by anything).
One way to check might be to lift the front wheel off the ground by lifting from the frame and trying to move the headstock laterally (fore/aft or side/side, not turning). If there is play, you might be looking at worn bearings (though I can't say for sure how much play would be expected from serviceable OEM bearings without further research).

I just got my bike back from the dealer after a maintenance service. 36,000 km/22,000 miles on the bike and they suggest I replace the bearings.


So, the wobble I feel is likely the bearing.
 

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I just got my bike back from the dealer after a maintenance service. 36,000 km/22,000 miles on the bike and they suggest I replace the bearings.


So, the wobble I feel is likely the bearing.
It absolutely could be the bearings. I wasn't trying to say it definitely wasn't the bearings, just that the particular symptom can be caused by any number of issues.

I've also had shops tell me I need to replace certain parts based on one symptom, though the suggested parts were actually not the cause of the problem. As an extreme example, my father's van started having engine and/or transmission problems. They started replacing a few pieces at a time, each time claiming that one or two parts and the problem would be solved. A few months and many many trips to the shop and literally half an engine worth of new parts later, all he had to show for it were several big receipts and a van with half a new engine and the exact same problem it rolled into the shop with in the first place.

Not all shops for sure, but I tend to want a little more to go on than "the guy at the shop said so" myself. I'd suggest first checking what you can check yourself for free and see if anything helps. I'd start with tire pressures and tread wear. If those checked out, I might re-torque the stem nut. Many people have reported their wobble went away after properly tightening the stem. Provided you have (or have access too) the tools required, this would only cost you some time. If that all checked out and the wobble was still present, then I'd start questioning the condition of the bearings.

It's entirely possible the guys at your shop are great guys and have already checked all this for you. It's also entirely possible the guys at your shop noted a bit of a wobble and thought they could sell you on a couple hundred worth of parts and labour whether it was the cause of your problem or not. Entirely up to you how you want to proceed, just trying to offer potentially cost saving suggestions.
 

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Just over 15,000 miles on the odometer and replaced mine last night. Those suckers were completely shot.

Next up, fork rebuild because those are basically shot as well.

Oh, and I noticed a bit of cupping on my front tire, so I get to replace that, too. This one really sucks, because it's not very old and has a lot of tread left.
 

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Just over 15,000 miles on the odometer and replaced mine last night. Those suckers were completely shot.

Next up, fork rebuild because those are basically shot as well.

Oh, and I noticed a bit of cupping on my front tire, so I get to replace that, too. This one really sucks, because it's not very old and has a lot of tread left.

Lets face it folks. Nothing is made like it was in the past. If it is not the materials, its the worker that does not give a damn about quality. :frown2:
 

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Lets face it folks. Nothing is made like it was in the past. If it is not the materials, its the worker that does not give a damn about quality. :frown2:
The tire is cupping due to the bearings, so that's completely on me.

Funny story: I called the Kawasaki dealership and their service guy told me there's no way my bearings needed replaced and asked if I wasn't sure my exhaust was loose - this was after he condescendingly called me darling. :blowup: For the sake of wanting a good laugh, I told him to just give me the quote (no way they were doing it after that), he said $400 for parts, labor, and disposal. I thanked him, said I'd check my schedule, and asked for a recommendation in the local sportbike riders Facebook group. They put me in contact with a guy who's worked on AMA riders' bikes for years - he quoted me $50 for labor, and I would bring the parts. The parts were $37 shipped. I ended up giving him $100 because I felt extremely guilty after all the effort it took to get the old ones out. Even with the extra, it still only cost me $137 AND he didn't question me about whether they needed replaced. He did point out that I probably should've done it several thousand miles ago, though. :blush:
 

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The tire is cupping due to the bearings, so that's completely on me.

Funny story: I called the Kawasaki dealership and their service guy told me there's no way my bearings needed replaced and asked if I wasn't sure my exhaust was loose - this was after he condescendingly called me darling. :blowup: For the sake of wanting a good laugh, I told him to just give me the quote (no way they were doing it after that), he said $400 for parts, labor, and disposal. I thanked him, said I'd check my schedule, and asked for a recommendation in the local sportbike riders Facebook group. They put me in contact with a guy who's worked on AMA riders' bikes for years - he quoted me $50 for labor, and I would bring the parts. The parts were $37 shipped. I ended up giving him $100 because I felt extremely guilty after all the effort it took to get the old ones out. Even with the extra, it still only cost me $137 AND he didn't question me about whether they needed replaced. He did point out that I probably should've done it several thousand miles ago, though. :blush:

Good for you, DARLING ...................:x
 

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Rogue, did you go OEM or aftermarket for your bearings? Any idea what your fork rebuild will cost?
Aftermarket AllBalls for the bearings, and I should know in a few days what the fork rebuild will cost, though I'm expecting probably about the same - which, IMHO, is beyond reasonable.
 
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