front forks "clunk" on rebound after going over drops / into potholes - Stromtrooper Forum : Suzuki V-Strom Motorcycle Forums
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post #1 of 48 Old 10-23-2017, 03:55 PM Thread Starter
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front forks "clunk" on rebound after going over drops / into potholes

Now that Electricals are sorted, time to figure out this front end clunk.

my bike:
K3 DL1000

I noticed the front end "clunked" when I went over surfaces that had a drop following it- since I was mostly road riding, it did this very infrequently. It is not a fairing sound- it seems to come from inside the front forks. It only happens on rebound- not compression/bottoming out. Or when the front tire comes off the ground from acceleration or dropping off a curb. The sound and feeling in the handlebars happen when the front suspension is not in the compression cycle.

Now, after spending last week riding a few hundred miles of forest service roads and UTV trails in the Black Hills, I noticed (and the guys with me could hear it when riding near me) the "clunk" happening more and more often (one shouted as he rode next to me- "is that supposed to sound like that?"). On one particularly rough decent, the front end would clunk after every rock/drop/bump - which was basically every 2-4 meters. Go over a rock (when the fork is at the end of rebound) and CLUNK! Wheelie over a rise and CLUNK when the front tire comes off the ground. Slowly navigate a rough/rocky descent and CLUNK... CLUNK... CLUNK... every time the forks fully extend.

The previous owner has paperwork showing they bought and had the dealer install Gold Valves.

A few months ago, I replaced the fork seals and put in new oil, thinking that not enough oil might affect the dampening and be the cause from a leaky seal. No luck.

So basically I think my only option is to tear the forks apart and see what I see- I am just not sure what I am looking for.

I have read many of the posts about front end "clunk" on the Wee- much of that seemed to be in the fairing and or mid stroke on compression. This seems to have everything to do with the rebound dampening - especially at the very end.

I'll post a video of the clunking sound and link to it tonight.

Does anyone have experience with dampening issues or thoughts?
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post #2 of 48 Old 10-23-2017, 04:38 PM
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Low oil level, or someone forgot to reinstall the top out spring?


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post #3 of 48 Old 10-23-2017, 04:39 PM
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Or a damper rod unscrewed from the cap?


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post #4 of 48 Old 10-23-2017, 11:32 PM
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The first thing I would check is the nut between the handlebar clamps for proper torque.

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post #5 of 48 Old 10-24-2017, 10:37 AM Thread Starter
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Sounds like some good ideas to check, I need to get a shop manual to check and make sure everything that is supposed to be in the forks are there. I put everything back together the same way it was when I installed new fork seals and oil this spring. Since I didn’t change anything, makes sense that it is the same clunk issue as before.

I purchased the Tech Spark manual... while it has ok information, the app to use it on mobile devices is severely lacking.


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post #6 of 48 Old 10-24-2017, 11:36 AM
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Check the head bearing and make sure its not too loose. A common reason for a clunk if there is too much play.

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post #7 of 48 Old 10-24-2017, 11:56 AM Thread Starter
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Also, maybe to clarify, the sound is more a “bang” than just a passive sound.

That being said, I’ll check the external bolts first before tearing apart the forks.


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post #8 of 48 Old 10-25-2017, 10:25 AM
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1. get the front wheel off the ground to provide at least minimal clearance below tire. If you have a center stand, someone on the passenger seat should be sufficient.

2. from a kneeling position in front of the bike, grab the forks. pull them forward and push them rearward.

3. if you detect any free play, you've located the source of your thunk. it is your bearing. It needs tensioning.

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post #9 of 48 Old 10-25-2017, 10:38 AM
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and...

once you've torqued them just to the point of eliminating this play, slowly rotate to the steering stop in both directions. wheel still elevated.

if any detents are felt in either direction, the bearings have developed a flat spot on their face and race interface (fun to say).

See chapter on steering bearing replacement.

EDIT: Loose bearings that make the hammering noises you have described pound flat spots into their race/face interface

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Last edited by Nostromdumbass; 10-25-2017 at 11:27 AM.
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post #10 of 48 Old 12-11-2017, 03:55 PM
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Any update on this from the OP?

I'm clunking too ... going to do some of the suggested checks. Also on a K3, 40K miles.
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