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I have a new DL 650 2018 with PL3112CAM givi luggage rack. The issue I have is that the luggage rack vibrates around 4500-5000 RPM.

Under 4500 the engine is butterly smooth, but when you hit that certain RPM range, it suddenly changes and becomes unpleasant. It is quite annoying as the whole seat vibrates and makes the ride unenjoyable at this particular RPM range. No vibration on mirrors. It is there on all gears, and stops when I pull the clutch.

Also, when I haveside cases (also Givi) mounted on the racks, the vibrations stop. But I don't use side cases often, I usually ride without them. I tried to removing the luggage racks, then the motorcycle works fine and no vibrations. After putting them back, the vibrations are back there.

I tried putting rubber washers to all places where metal to metal connects in those racks (footpegs, under the seat etc) - didn't help much. I visited dealer 2 times and reported it - they weren't able to help much. I also visited 2 local services - not very helpful either.

So my question is, do you have any idea what the solution could be?

Is anyone else having the same combination of bike + racks that could let me know how that works on his bike?

Can the issue be somewhere else, and vibrations on the luggage rack is just the effect of underlying issue? :confused::confused::confused:
 

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Although I don't have the givi racks, my recollection is the "latches" that turn from red to green are small blocks of aluminum with spring steel retainers, the blocks are probably rattling since the springs weren't very strong as I remember. Unfortunately I can remember how they go together, maybe a small tye wrap would hold the blocks "in" and just snip the tye wrap when you want to use the boxes.

You probably can experiment in the garage by just squeezing various bits and revving it up.


Good luck
 

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VTWEE:

Maybe he has the dreaded 5K-Plus vibration issue that some others do here on the forum??!

Ross

Although I don't have the givi racks, my recollection is the "latches" that turn from red to green are small blocks of aluminum with spring steel retainers, the blocks are probably rattling since the springs weren't very strong as I remember. Unfortunately I can remember how they go together, maybe a small tye wrap would hold the blocks "in" and just snip the tye wrap when you want to use the boxes.

You probably can experiment in the garage by just squeezing various bits and revving it up.


Good luck
 

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I have the same racks for my '17 dl650 waiting at home for me to install; I am currently in Egypt but will be home soon.

I am an avid bowhunter and there are some marvelous vibration dampening products on the market for archery tackle - has anyone tried something like that? I bet there are areas on the pannier racks where something loke this could be used. I am not sure if it (dampening products) can take the sustained vibration of a motorcycle, but for the marginal cost involved I may try some when I install the racks and panniers.

* I have some vibes coming through my T-Rex crash guards on my bike at the same rpm range (~5k). I just push through that range to cope. There are better options I am sure...

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No fix for the actually engine problem causing the vibration resonance in various locations and accessories. Suzuki is always surprised to hear there are issues, bastards. Maybe this week will shed some light from suzy? Starting to hold my breath now...
 

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No idea but I've used weatherstripping to stop a rattle before. The kind that has one side sticky.
 

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Discussion Starter #8
No fix for the actually engine problem causing the vibration resonance in various locations and accessories. Suzuki is always surprised to hear there are issues, bastards. Maybe this week will shed some light from suzy? Starting to hold my breath now...
Is this a problem common only for this model, or also for other "modern" bikes of other manufacturers as well? (BMW GS, Africa Twin, Tiger etc)? I also have an Aprilia RST Futura 1000 from 2001 and I though that a new 650 will be less viby :wink2:
 

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The racks are not supported all around. The bits that are not supported act similar to a tuning fork: If there is a vibration in the bike at or near the resonant frequency, it will vibrate the rack with increasing amplitude. So it's not surprising that there is a specific RPM where the vibration occurs, regardless of the gear you're in.

You can move the resonant frequency, and thereby the RPM where this effect occurs, by adding a little weight to the rack. It takes surprisingly little weight (maybe around 100 grams) to move it to an RPM range that you don't normally use.

So start a little experimentation. Use zip-ties or duct-tape to attach some weights (a few nuts and bolts, say), to the unsupported part of the rack. Go for a test ride to see where the resonation occurs. Play with different weights until you're happy, then go for a permanent mounting.

Crash bars typically have the same problem. My (Givi) crash bars came with a few rubber blocks that could be installed on them, in different locations, to play with the resonance frequency as well. I found I did not need them, but others may.

Damping the oscillations, by adding rubber washers and such, may reduce the severity of the vibration but won't alter the resonant frequency.
 

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This is great, I am going to try this when I get home and install my panniers.
The racks are not supported all around. The bits that are not supported act similar to a tuning fork: If there is a vibration in the bike at or near the resonant frequency, it will vibrate the rack with increasing amplitude. So it's not surprising that there is a specific RPM where the vibration occurs, regardless of the gear you're in. Crash bars typically have the same problem.

You can move the resonant frequency, and thereby the RPM where this effect occurs, by adding a little weight to the rack. It takes surprisingly little weight (maybe around 100 grams) to move it to an RPM range that you don't normally use.

So start a little experimentation. Use zip-ties or duct-tape to attach some weights (a few nuts and bolts, say), to the unsupported part of the rack. Go for a test ride to see where the resonation occurs. Play with different weights until you're happy, then go for a permanent mounting.
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I'm not sure if it's a common problem, I rode a demo bike a few weeks prior to purchasing mine and the demo bike didn't buzz like mine does. I can't speak to the other bikes you asked about, but my Versys 650 (2011) which is supposed to be buzzy was way better than my vstrom, I had a 03 Aprilia Caponord v-twin 990 rotax, didn't buzz. Even my 05 vstrom 650 didn't buzz, had some off idle fueling issues and single spark plug heads, it would surge but they all did it.
 

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Ok guys, so I did some tests today and here are results. I can confirm that adding weight to luggage racks decreases vibrations. However...

I firstly started with 1kg weight that I use for diving and attached it to the rack. 1kg on both sides, then a test ride. I felt that the vibrations decreased, but I still felt them, so I returned to the garage to put more weight on. It seems that the more weight I was putting on, the less I felt the vibrations. I don't think that adding 100 or 200 grams would make any difference.

So after 3 test rides I ended up with 1.5 liter bottle of water attached to my crash bars, and 2 weights on my luggage rack - around 2kg on each side of the luggage rack... In total, + around 7kg on the bike.

The vibrations were reduced by 70 - 80% with that weight, but they were still present. I felt a little bit on the seat, and a little bit on the footpegs, but very minor.

I'm wondering what to do now. Seems that adding weight helps, but I think that to feel a significant difference there is a lot of weight needed, and the bike becomes heavy. On top of that, I would have to store that weight inside crash bars and luggage racks.

Please let me know if you have any suggestions :wink2:
 

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Hmm. I had not expected that. Well, it was worth testing I guess.

If it's a vibration similar to a tuning fork, then the movement is in-out at both sides simultaneously. (So the movement is "in" at the same time, and "out" at the same time.) What could possibly help then, is to connect both ends via something rigid underneath the seat. That would prevent the in-out movement.

It's hard to tell from your pictures, but it looks like if you run a ratchet strap or something from one side to the other, it should clear your rear wheel. That strap may prevent the "out" movement and reduce your vibrations by a lot. If it works, then you can later replace this with something more rigid.

The other thing that I'm thinking about is aerodynamic buffeting. I think it is less likely since your symptoms seem to be tied into a specific RPM rather than speed. But hey, who knows? If you want to test for that you need to alter the air flow around the frame. Simply take a bit of electric wire or fuel hose and spiral it around the rack frame. That should be sufficient to alter the aerodynamics. It's probably a long shot, but since you're experimenting anyway...
 

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I don't think that it is caused by aerodynamic buffeting, as the vibrations are present even on neutral, at 0 km/h. I don't feel them increase / decrease with speed, rather with the engine RPM. The ratchet strap might be worth trying, but maybe I will figure out some kind of a toolbox for both sides and just store some tools there. If their weight will be enough, the vibrations should be gone, but that will need some custom work to assembly.
 

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Ok guys, so I did some tests today and here are results. I can confirm that adding weight to luggage racks decreases vibrations. However...

I firstly started with 1kg weight that I use for diving and attached it to the rack. 1kg on both sides, then a test ride. I felt that the vibrations decreased, but I still felt them, so I returned to the garage to put more weight on. It seems that the more weight I was putting on, the less I felt the vibrations. I don't think that adding 100 or 200 grams would make any difference.

So after 3 test rides I ended up with 1.5 liter bottle of water attached to my crash bars, and 2 weights on my luggage rack - around 2kg on each side of the luggage rack... In total, + around 7kg on the bike.

The vibrations were reduced by 70 - 80% with that weight, but they were still present. I felt a little bit on the seat, and a little bit on the footpegs, but very minor.

I'm wondering what to do now. Seems that adding weight helps, but I think that to feel a significant difference there is a lot of weight needed, and the bike becomes heavy. On top of that, I would have to store that weight inside crash bars and luggage racks.

Please let me know if you have any suggestions :wink2:
Go with a 16 tooth counter sprocket, this will lower the RPMs at freeway speed and cut the vibrations down as well, win win. I just install the same racks and experiance the same vibration.
 

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I've been riding with cases for three years and have never experienced this problem - with cases on or off. Now with GIVI crash bars I did have a vibration problem at 5k rpm but fixed that problem with rubber tubing and metal adjustable clamps at the point that right and left met at bottom and the issue has never come back. I would double check your rack installation, because you must have an installation issue. Check the cross bar at the rear that connects the left and right rack together and make sure that installation is correct and tight. If installed upside down it will leave a gap top to bottom that would defiitely vibrate.
 

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No fix for the actually engine problem causing the vibration resonance in various locations and accessories. Suzuki is always surprised to hear there are issues, bastards. Maybe this week will shed some light from suzy? Starting to hold my breath now...
Sorry, but that's incorrect :)

I suffered from the ~5000 rpm vibrations (would get hand numb and it was impossible to maintain highway speed); took it to the dealer, they spent 30 minutes tightening everything to specs (including thrust adjuster) and I'm now a happy camper. Best $70 spent on the bike.
 

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Checking the trust adjusters is always a good first step. Many are not set to the right torque. BUT you need the special tool to undo the counter nuts.

Next any harmonic vibration can be effected/ changed by putting some force on the vibrating part. It will dampen the harmonic vibration. So experiment with a small ratchet strap to put stress on the offending part and see if it fixes it. If yes find a more permanent solution.
 
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