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Vibration when turning and resonance

omniphil said:
Has anyone heard anything about parts from BMW to fix this issue yet? it's been a few months....
Click to expand...
Yes, took my dealer (Canada) quite a bit of digging through "puma" cases. He has found a replacement motor mount assembly that should be installed by end of month.
Sorry, no part number. Will post when I have it.
 
Finally got the issue fixed via the service bulletin. Seems like they have put in a stiffer motor mount. I do feel the engine more through the bike now, but the annoying resonance/vibration is gone.
 
crackanoon said:
what did you discover causing the vibration
Click to expand...
I found two causes for the engine vibration transfer.
1. the mounting bolt was way too tight, not allowing the cantilever part of the mounting to move .
2. the main cause of the vibration transfer is the slotted washer that under operation it touches ,ever so slightly, the outside of the mounting. this is enough for the vibration
to be transferred into the body of the scooter.
The fix:
1. Remove the nut and slotted washer on the right end side.
2. fit a copper washer with a 16mm inside diameter into the the bolt (photo)
3. fit the slotted washer back but this time with the slotted faces in the horizontal position ( see photo )
4. tighten the bolt again with just a good snug. Do not over tighten it.
In my scooter this simple mod totally transformed the smoothness of the bike.
 

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MikeC said:
I found two causes for the engine vibration transfer.
1. the mounting bolt was way too tight, not allowing the cantilever part of the mounting to move .
2. the main cause of the vibration transfer is the slotted washer that under operation it touches ,ever so slightly, the outside of the mounting. this is enough for the vibration
to be transferred into the body of the scooter.
The fix:
1. Remove the nut and slotted washer on the right end side.
2. fit a copper washer with a 16mm inside diameter into the the bolt (photo)
3. fit the slotted washer back but this time with the slotted faces in the horizontal position ( see photo )
4. tighten the bolt again with just a good snug. Do not over tighten it.
In my scooter this simple mod totally transformed the smoothness of the bike.
Click to expand...
Going to give this a try, it is interesting as the service manual shows the washer should be vertical with 180Nm torque.
 
omniphil said:
Has anyone heard anything about parts from BMW to fix this issue yet? it's been a few months....
Click to expand...
the vibration issues got fixed thanks to a member here that pointed out to me the bolt that goes thrue the engine ,and the nut is under the exhaust. those cannot be tightened too hard. just snug and all vibrations were gone on mine, just with this alone.
 
I do same as you describe and vibration reduced greatly, the m16 bolt class 10.9 can be tighted up to 335 Nm, i dont know what is the proper torque for this bolt at BMW manual because i dont have access to one, but the amount of power required to untight was excessive high.
Also i saw underneath the engine is a secondary bracket called (auxiliary-swing-arm) in the way to fore, which has a bolt and (3 items marked as 11) and an adjusting nut working as friction plate or so, any one with some informations please about adjustment...
 

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MikeC said:
I found two causes for the engine vibration transfer.
1. the mounting bolt was way too tight, not allowing the cantilever part of the mounting to move .
2. the main cause of the vibration transfer is the slotted washer that under operation it touches ,ever so slightly, the outside of the mounting. this is enough for the vibration
to be transferred into the body of the scooter.
The fix:
1. Remove the nut and slotted washer on the right end side.
2. fit a copper washer with a 16mm inside diameter into the the bolt (photo)
3. fit the slotted washer back but this time with the slotted faces in the horizontal position ( see photo )
4. tighten the bolt again with just a good snug. Do not over tighten it.
In my scooter this simple mod totally transformed the smoothness of the bike.
Click to expand...

Hi,

Just purchased a c400x and experiencing the same issue. I see that this post is quite old. Is your fix still working?

Also, Do you need to remove the fairings to make this update or is it accessible under the bike?

TIA
 
Farklepilot said:
Will be taking mine in as well. Sure seems like a motor/pivot mount issue to me. Will advise here what the outcome is.
Click to expand...
Hello, I have a C400GT that also makes a kind of vibration or resonance when cornering and mostly above 50km/h, I suspect it is from the engine mounts, although I checked and they do not appear to be damaged or broken rubber but there is something that is not Normal for engine mounts, on both sides of the bike you can see that they are not on the axis, they are not centered which does suggest some damage. Was it resolved with your motorbike?? what did they do? thanks.
 
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