Vibration in grips at 3k-5k RPM...any way to correct?

[po18guy]

Right down to the metallurgy! Seriously,

1. Factory mirrors revealed only my shoulders which I know I have.

2. No room for bar ends when more usable mirrors take their place.

3. Being the pragmatist that I am, it all works so I stopped right there.

I might just weigh one of each to see the difference in mass, but it is academic at this stage.

[Lucky Phil]

31 minutes ago, po18guy said:

Right down to the metallurgy! Seriously,

1. Factory mirrors revealed only my shoulders which I know I have.

2. No room for bar ends when more usable mirrors take their place.

3. Being the pragmatist that I am, it all works so I stopped right there.

I might just weigh one of each to see the difference in mass, but it is academic at this stage.

Ok so I must have misread your post. With your setup there is no/acceptable/better than stock bar vibration?

Ciao

[po18guy]

4 hours ago, Lucky Phil said:

Ok so I must have misread your post. With your setup there is no/acceptable/better than stock bar vibration?

Ciao

Did not ride it extensively in stock form. On the motorways, I had to have better mirrors - vibration or not. Thankfully, it may be the combo of rubber-mounted tubular bars and enough weight on the ends of those bars that 4K+ RPM is nice and sweet. The taper of the bars as well may have been engineered to help with vibes. Although somewhat counter-intuitive to me, that taper may just have moved the harmonics higher than the exciting forces.

[po18guy]

So, for the sake of discussion, I weighed the OEM bar ends with hardware and my current Ken Sean bar-end mirror with approximate mounting hardware.

OEM bar end w/bolt and brass wedges: 421 grams

Ken Sean rectangular bar end mirror w/hardware: 397 grams. 

The bar-end mirror is 94.5% of the weight of the OEM bar-end. A potential advantage of the weight being in the form of a mirror at bar's end is that The mirror places the weight further from the focal point of excitation (handlebar clamp), and the dampening effect of airflow on the mirror certainly has some influence on energy dispersion. 

Of note, the favored Napolean mirrors may very well weigh more than the Ken Sean. Someone else may be able to weigh one complete with hardware for comparison. The major caveat is that the effect I have noted is on the above the triple, rubber-mounted, tapered alloy bars as found on the Ballabio, Cafe Sport, Coppa, Scura and a few others. 

NOTE: This has not been tested in the Guzzi wind tunnel. Another casualty of Covid.

[docc]

I'll play! I don't have any Napoleans anymore, but Scud might throw in and weigh one for us. My little CRG only weigh 110 grams, but I added them to the barend weights, having taken some metal off for the mounting points.

And +1 on grip selection. The factory grips on my Sport were ridiculously thin and hard. From early on, I've used these gel ProGrip Superbike grips (made in Italy!) . . .

[VtwinStorm]

3 hours ago, docc said:

I'll play! I don't have any Napoleans anymore, but Scud might throw in and weigh one for us. My little CRG only weigh 110 grams, but I added them to the barend weights, having taken some metal off for the mounting points.

And +1 on grip selection. The factory grips on my Sport were ridiculously thin and hard. From early on, I've used these gel ProGrip Superbike grips (made in Italy!) . . .

Great advice, Docc.

[po18guy]

Perhaps the only place on a V11 where a few grams actually make a difference.

[Lucky Phil]

I read from a knowledgeable source that these improve the situation. No responsibility accepted as I don't have any first hand experience with them myself.

https://www.motorcyclespareparts.eu/en/piaggio-parts/ap8104572

 

Ciao

[VtwinStorm]

45 minutes ago, Lucky Phil said:

I read from a knowledgeable source that these improve the situation. No responsibility accepted as I don't have any first hand experience with them myself.

https://www.motorcyclespareparts.eu/en/piaggio-parts/ap8104572

 

Ciao

https://www.af1racing.com/Antiv-weight-black-AP8104572-ex-AP8102579

According to AF1, these don't fit a V11 Sport.

 

[Lucky Phil]

7 minutes ago, VtwinStorm said:

https://www.af1racing.com/Antiv-weight-black-AP8104572-ex-AP8102579

According to AF1, these don't fit a V11 Sport.

 

Probably because that's just cross referencing the P/N. Plenty of stuff fits but naturally doesn't cross reference, that's what "tuning" and "mods" are all about.

Ciao  

[po18guy]

I had to fabricate the internal wedge mounts for the mirrors I bought. I obtained some Delrin stock and bored, angle cut and fit them. Bar ends to a certain degree, are universal. A pair linked above are $102 USD, quite a chunk, but they are steel powdercoated black and listed for the V11.

But, all of this traces directly back to the tune of the engine, since the reciprocating/rotating mass is unchanging. Valve adjustment to a degree, but throttle plate synch (at cruising RPM range) to a much greater degree will affect the smoothness of which the engine is capable. 

First things first they say, and these drop out of perfect tune fairly easily.

[VtwinStorm]

31 minutes ago, Lucky Phil said:

Probably because that's just cross referencing the P/N. Plenty of stuff fits but naturally doesn't cross reference, that's what "tuning" and "mods" are all about.

Ciao  

Just making sure... I'll order a set for my V11.

[docc]

20 minutes ago, po18guy said:

I had to fabricate the internal wedge mounts for the mirrors I bought. I obtained some Delrin stock and bored, angle cut and fit them. Bar ends to a certain degree, are universal. A pair linked above are $102 USD, quite a chunk, but they are steel powdercoated black and listed for the V11.

But, all of this traces directly back to the tune of the engine, since the reciprocating/rotating mass is unchanging. Valve adjustment to a degree, but throttle plate synch (at cruising RPM range) to a much greater degree will affect the smoothness of which the engine is capable. 

First things first they say, and these drop out of perfect tune fairly easily.

+1. Well said, Sir!

[po18guy]

Thank you. I have not ridden a clipon equipped V11. There is undoubtedly a difference in felt vibration between the bar styles: shorter and solidly mounted vs. longer and rubber-mounted. It requires some pondering of the physics involved to determine which style vibrates more unacceptably, as to frequency and amplitude of vibration.

Are we discussing band-aids here? A good painstaking tune-up might just render all of this moot.

[VtwinStorm]

I would just be happy as a clam if I could just mount a set of chrome Napoleon bar end mirrors and some rubber plugs for the original mirror screw holes... I've seen Napoleons mounted on a V11 Sport with clipons, and I think the extra weight would smooth out the handgrip vibration I'm experiencing.

Also, the chrome Napoleons would compliment the chrome headlight ring, chrome Mistral cans, and instrument bezels. It would just work so nicely on this machine.

Anyone mount Napoleons on their V11 Sport?