Head Knocking

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SPORT

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After reading several posts regarding steering head nut loose, Wild72 and I decided to adjust the torque on the steering head nut and it felt better...for a while. During my road trip however, it became very pronounced and would knock every time I rode over bumps in the road. It can also be felt/heard when applying front brakes. Several days after the trip, I unloaded the luggage and went for a country stroll. Although the knocking is still there when riding over bumps and/or applying front brakes, it is less pronounced. I've since checked the torque of the steering head nut, but the head still knocks. It feels as though the bearing seats were never seated all the way and torqueing the nut only compresses the seats, thus never really seating.

Any thoughts?

 
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Did you go through the service manual process to a T?

You make it through the very specific process of loosening, tightening, loosening, and tightening? What specific values did you use? Your torque wrench was how close to the 90 degree mark indicated? How'd you hold the triple clamps still to reach initial torque?

I found that process full of potential flub points, tough angles, and hard to reach initial torque.

 
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Sounds like something is still loose and/or broke.com.

I had to re torque my 06 at about 600 miles. It's been fine since 25k later. When I tear it down to do the valves after NAFO/Trip out west I may put in the tapered bearings.

Can you reproduce the sound/clunk/play with the bike on the center stand, front wheel jacked off the ground, grabbing the forks by hand and moving them around?

 
Did you go through the service manual process to a T?
You make it through the very specific process of loosening, tightening, loosening, and tightening? What specific values did you use? Your torque wrench was how close to the 90 degree mark indicated? How'd you hold the triple clamps still to reach initial torque?

I found that process full of potential flub points, tough angles, and hard to reach initial torque.
To a T? Well, uhh, not exactly. I think after 10 years of working on airplanes and my own mechanical toys, the process is pretty straight forward. Torque to 35ft lbs then back off to 14ft lbs. My experience taught me to not fight over the 2-3 ft lbs (if that) difference it makes whether the potential flub/angle points are all covered or not.

Sounds like something is still loose and/or broke.com.
I had to re torque my 06 at about 600 miles. It's been fine since 25k later. When I tear it down to do the valves after NAFO/Trip out west I may put in the tapered bearings.

Can you reproduce the sound/clunk/play with the bike on the center stand, front wheel jacked off the ground, grabbing the forks by hand and moving them around?
Broke? Holy crap I hope not! That could end in a tragedy...and I hate tragedies. The steering moves with relative ease when lifted and does not bind.

I can only reproduce the 'knock' when coming to an abrupt stop. I can not reproduce the sound/feeling when on a center stand.

I guess I'm asking two things.

1) is it possible that bearing seats were never set properly?

2) Is it possible to bottom out on the threads resulting in a false torque setting? If so, what's the resolve; spacers?

Thanks for the insights

 
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To a T? Well, uhh, not exactly. I think after 10 years of working on airplanes and my own mechanical toys, the process is pretty straight forward. Torque to 35ft lbs then back off to 14ft lbs. My experience taught me to not fight over the 2-3 ft lbs (if that) difference it makes whether the potential flub/angle points are all covered or not.
I wouldn't sweat the 2-3 lbs either. And your recitation of torques indicates proficiency better than some who post. It's hard to remember where each of our thousands of members is at on that scale. ;)

However, if I have a clunking front end ...I'd be second-guessing and perhaps follow them to the letter just to take out variables.

Also, did you elevate the front end or just centerstand it when you torqued?

Otherwise, I'd be thinking the broken angle...or maybe races are moving around. I dunno.

 
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I don't want to suggest that you aren't doing it right, but what nut are you adjusting? You have to remove the external nut, then remove the locking device, then adjust the bearing nut. If that nut is torqued to the spec, it is hard to believe there is enough slop to acutally HEAR it. My bike has a clunk that comes from the brake caliper that sounds like it coulc be the steering bearings loose. That clunk from the calipers is a pretty common thing and nothing to worry about.

Motorcycle-ed

 
OK,

Went out and played with it a bit. the sound could be coming from the steering head, but I'm also beginning to wonder if it might also be the front suspension. With both wheels down, I roll the bike forward 6" then grab front brakes and compress the forks a bit I can then here a sound (something between a "click click" and a "clunk clunk" (if that makes since)). One sound while compressing the forks and the other sound while extending the forks. If listening carefully I almost hear a double click as it compresses; like one click from each fork???

Again, I can feel it in the handle bars as well.

any thoughts?

 
I don't want to suggest that you aren't doing it right, but what nut are you adjusting? You have to remove the external nut, then remove the locking device, then adjust the bearing nut. If that nut is torqued to the spec, it is hard to believe there is enough slop to acutally HEAR it. My bike has a clunk that comes from the brake caliper that sounds like it coulc be the steering bearings loose. That clunk from the calipers is a pretty common thing and nothing to worry about.Motorcycle-ed

Yes, I removed the top triple tree, removed the lock and first stop nut, then torqued the head nut. I then re-installed the stop nut, the lock and re-installed the bars and tightend the fork clamp bolts and the main head bolt.

I have looked into the brake calipers, but the sound seems to originate at the top of the triple clamp.

 
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OK,
Went out and played with it a bit. the sound could be coming from the steering head, but I'm also beginning to wonder if it might also be the front suspension. With both wheels down, I roll the bike forward 6" then grab front brakes and compress the forks a bit I can then here a sound (something between a "click click" and a "clunk clunk" (if that makes since)). One sound while compressing the forks and the other sound while extending the forks. If listening carefully I almost hear a double click as it compresses; like one click from each fork???

Again, I can feel it in the handle bars as well.

any thoughts?
Is little nub properly aligned in the ABS sensor ring?

 
any chance your clunk is no longer the bearings but is actually the brake rotors?



I don't want to suggest that you aren't doing it right, but what nut are you adjusting? You have to remove the external nut, then remove the locking device, then adjust the bearing nut. If that nut is torqued to the spec, it is hard to believe there is enough slop to acutally HEAR it. My bike has a clunk that comes from the brake caliper that sounds like it coulc be the steering bearings loose. That clunk from the calipers is a pretty common thing and nothing to worry about.Motorcycle-ed

Yes, I removed the top triple tree, removed the lock and first stop nut, then torqued the head nut. I then re-installed the stop nut, the lock and re-installed the bars and tightend the fork clamp bolts and the main head bolt.

I have looked into the brake calipers and rotors, but the sound seems to originate at the top of the triple clamp.

 
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OK,
Went out and played with it a bit. the sound could be coming from the steering head, but I'm also beginning to wonder if it might also be the front suspension. With both wheels down, I roll the bike forward 6" then grab front brakes and compress the forks a bit I can then here a sound (something between a "click click" and a "clunk clunk" (if that makes since)). One sound while compressing the forks and the other sound while extending the forks. If listening carefully I almost hear a double click as it compresses; like one click from each fork???

Again, I can feel it in the handle bars as well.

any thoughts?
Is little nub properly aligned in the ABS sensor ring?
Where is the ABS sensor ring located? and how would I go about aligning it?

 
Your description of the sound and what produces it is an exact match for when the front brake disks were slightly loose on my 04 FJR. Both disks were replaced by Yamaha as a safety issue at 42,000 miles, no charge.

There was only slight movement in the disks, but I was told there should be no movement that you can see or feel.

Longrider

 
Where is the ABS sensor ring located? and how would I go about aligning it?
The black metal thing on the port side of the bike....about 4 inches in diameter that the ABS sensor is seated in....with the one electrical wire coming out. It's not unommon on reassembly to not align it properly. There are two little embossed doohickeys on the ring that should flank a little raised doohickey on the fork. If not inside the notch the ring could move.

 
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Your description of the sound and what produces it is an exact match for when the front brake disks were slightly loose on my 04 FJR. Both disks were replaced by Yamaha as a safety issue at 42,000 miles, no charge.There was only slight movement in the disks, but I was told there should be no movement that you can see or feel.

Longrider
I'll look into that.

Thanks for the heads-up.

 
any chance your clunk is no longer the bearings but is actually the brake rotors?

That was my next comment. There is a mechanical 'clunk' associatd with the rotors/callipers. I hear it every now and then, especially with abrubt stoppages, and understood that to be "normal".

-MD

 
I vote for brake rotors or caliper clunk. Mine does it sometimes. Especially since every duplication of the sound involves grabbing the front brake for you.

 
Here is one way to check.

1. Put the bike on the center stand.

2. Have a friend sit on the bike and pull the brake lever, and lean back, so that the front wheel is off the ground.

3. You set in front of the bike and grab both front forks and try to pull toward you and push away from you.

If the steering head bearing are loose, you will feel the movement in the forks and hear a clunk.

Hope this helps

Joc

 
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