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Discussion Starter · #1 ·
Short rant:

I was hit in an intersection a few months after purchasing my bike (minimal damage: clutch cover, mirrors, sliders, bar ends); the other driver’s insurance paid for the repairs. I got the bike back and drove it for a month or two but it never felt just right. The bike tracked straight, but it seemed the handlebars were off. I brought it back to the shop that did the repairs and all of the techs took the bike for a test ride, confirming that nothing was wrong. A few weeks later I brought the bike to another shop who immediately noticed that the forks were bent horizontally and vertically. The original claim for repairs was expanded and the front end of the bike was replaced (triples, bearings, front axle, etc). I picked the bike up a few weeks ago and the drive home felt amazing. I just had the suspension upgraded (Penske double, GPR re-valve) and it felt like a new bike. The next day I start it up to head to work and feel a strange ‘clunk’ sensation from the front end. I ignore the feeling, thinking that I’m crazy to assume anything else could possibly be wrong after just getting the bike back. Fast forward two weeks- I confirm that the steering head bearings are loose. I bring the bike back to the repair shop and they tighten the bearings up for me, test ride it and hand it back. The ride home was great! The next day...the lock nut on stem snaps right off, bearings loosen, and the fork wobbles. The dealership agreed to rush-ship the parts (apparently the lock-nut is bike specific), but I’m out of a bike again!

If something else goes wrong after this round of repairs, I don’t think I’ll mention a word of it to anyone. My friends think I’m losing my mind.

But my question is this- has anyone had any problems with the lock-nut or bearings? When my forks were replaced, all of the parts were ordered new. It seems strange (other than installment error) that the lock-nut would go this quickly. Just curious if anyone has experienced anything similar.
 

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When I fitted the steering damper to mine I also serviced the steering head bearings at the same time then when I removed the damper again the top nut would not tighten down again onto the top triple clamp.

The nut is capped and the thread on the steering stem was now to long so the nut did not quite reach the top clamp, I could not see or feel anything but I had a slight clunk under certain conditions when ridding.

My fix was to reuse the nut from the damper as it has no cap on it or a very thin spacer would have allowed the nut to seat down on the top clamp.

When they did the work on your bike they may have come up with the same problem I did and over tightened the lock nut ?
 

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If my bike needed steering head bearings I'd look into installing roller, not ball, bearings.
 

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The cap nut on your bike is an aluminum bit that is not designed to "load" the front end. Aluminum can't handle that stress. Few things to look at-
1) dealer shoudlv'e installed steering adjuster nuts (the spanner nuts under top triple clamp) properly, but may have not torqued them right, allowing the front end to wiggle and load the top clamp and aluminum cap nut.
2) dealer may not have installed bearings in facing right way, its unlikely, and you would probably have noticed a notchy front end.
3) someone may have left washer off between top clamp and cap nut allowing the nut to bottom out and crack. (most common)
4) fatigue of being on and off so many times may have cracked the top nut.
5) improperly assembly sequence, like tightening top clamps to forks and the putting on cap nut, allowing clamp to flex against the top cap nut.
I'm sure the dealer is as anxious as you to get it right, so good luck to you.
*I forgot to mention the obvious, don't over torque that top nut, it is a aluminum cap nut, not designed to hold the front end together.
 

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Discussion Starter · #5 ·
The cap nut on your bike is an aluminum bit that is not designed to "load" the front end. Aluminum can't handle that stress. Few things to look at-
1) dealer shoudlv'e installed steering adjuster nuts (the spanner nuts under top triple clamp) properly, but may have not torqued them right, allowing the front end to wiggle and load the top clamp and aluminum cap nut.
2) dealer may not have installed bearings in facing right way, its unlikely, and you would probably have noticed a notchy front end.
3) someone may have left washer off between top clamp and cap nut allowing the nut to bottom out and crack. (most common)
4) fatigue of being on and off so many times may have cracked the top nut.
5) improperly assembly sequence, like tightening top clamps to forks and the putting on cap nut, allowing clamp to flex against the top cap nut.
I'm sure the dealer is as anxious as you to get it right, so good luck to you.
*I forgot to mention the obvious, don't over torque that top nut, it is a aluminum cap nut, not designed to hold the front end together.

I feel like option four might have been the culprit. The forks had been on and off quite a few times and the lock-ring that fits in-between the two spanner nuts broke, allowing the top nut to start loosening itself. The dealer paid for the parts and re-installed everything and I don’t feel or see any movement from the bearings under the top triple. I have noticed with my hands off the bars that the bike tracks straight, but seems to be leaned over to the left. I noticed this before I had any fork work done. I checked the alignment numerous times (String-method) and it seems to be spot on. I wonder if it’s a characteristic of the bike.
 
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