Rubber Mounts for Norge Engine - anyone installed them?

[PJPR01]

Has anyone here experimented with placing a thin but hard rubber grommet or washer on the mounting bolts between the frame and the engine on a 2V Norge? 

I'm curious whether that would make the bike any smoother at higher revs and / or would it create any alignment issue with the CARC drive if say the washer was 1/8" thick?

The bike runs great, but there's a slight buzz above 75 mph in top gear that I would love to eliminate, and it's not valves, TPS or Throttle bodies as I've done those multiple times down to the finest level of tuning possible with Guzzidiag.  It's not annoying, I'd just love for it to be as smooth above 4k RPM's as it is below 4K or find whatever else it could be that creates that buzz...mind you, it's not enough to put my hand to sleep or anything.

[Lannis]

People have been trying to use rubber washers on motor mounts on bikes to damp vibrations for 70 years, and I've never heard from anyone that it's worked yet.

An engineered system like on a Yamaha RD400 or a Norton Commando or a late Sportster is different.   But if the cheap solution worked, the maker would probably have spent an extra $.75 per bike and done it from the get-go.

Lannis

[Two Checks]

Iffin ya want it that smooth, get a Gold Wing. 

[rtbickel]

Try filling the handlebars with lead shot or BBs

[PJPR01]

People have been trying to use rubber washers on motor mounts on bikes to damp vibrations for 70 years, and I've never heard from anyone that it's worked yet.

An engineered system like on a Yamaha RD400 or a Norton Commando or a late Sportster is different.   But if the cheap solution worked, the maker would probably have spent an extra $.75 per bike and done it from the get-go.

Lannis

All true Lannis!  I hear you...I was wondering from the 1400 thread where they say the engine is rubber mounted, they must have done it for a reason, in fact I'm wondering if I can find the washers from that model and see if they would even fit the Norge.

Gold Wing...too smooth, just the ever constant tinkering that a Guzzi inspires us to do...constant refinement in search of Guzzi nirvana!

 

[PJPR01]

Try filling the handlebars with lead shot or BBs

Interesting idea...I've got the super heavy Throttlemeister bar ends, wouldn't filling the handlebars (assuming it's hollow) make the steering heavy for maneuvering?

[stephenm]

The 1400 engine uses isolating engine mounts. They are substantial elements, not rubber washers. The engine is able to move around, obviously so at idle.

Stephen

[blackcat]

I have no idea if this works but they have been around for some time:
http://www.barsnake.com

[PJPR01]

I should clarify, it's the slight engine vibration that I'm trying to smooth, not something I am feeling in the handlebars...

[Wayne Orwig]

My Stelvio came with the turn signals in the mirrors, on the bars. Something about the turn signals in the body panel did not meet US specs or such. I got the Euro turn signals and installed those in the body like other countries had. And replaced the odd and fragile mirrors with normal mirrors. Instantly, the entire bike felt a LOT smoother, a LOT.

So don't rule out some other oddity resonating and making the vibration worse. Since I have not encountered a lot of 2V Norge owners complaining, I would suspect a loose body panel or some such making the vibration worse than normal.

[Don G]

If you want it to be really smooth you may have to alter the balance factor of the rotating assembly, good luck with that.  DonG

[PJPR01]

Thanks Wayne...I am hoping that's what it turns out to be, have been going methodically thru the bike tightening everything and haven't found the culprit yet, maybe it's a harmonic vibration that is just inherent in this motor...and if after exhausting ever single bolt and nut on this bike, that's how it will stay.  It's very enjoyable, I'm just doing an extreme fine tuning...can't resist tinkering with it!

Thanks all others for the suggestions!

 

[john fish]

I have no idea if this works but they have been around for some time:
http://www.barsnake.com

I put that in the Verlicchi clip-ons on my V11 Sport and they seemed to help.

When I had vibrations on my MZ SKorpion, it turned out to be a cracked lower triple tree.   

None of my Guzzis has ever had a vibration problem at revs over 4,000.  Just seems odd to me.   

[guzzisteve]

There is a company that makes a mercury(may not be) filled tube on a plate that goes on the flywheels of engines. It makes them dead smooth. I put one on an EV, it was boring. Pretty wild, I couldn't believe it, felt like a Honda but smoother.
If you like I can find info, Harpers used to sell them in 98-99.

[Huzo]

Really if you hope to isolate vibrations in this manner, you’ve to isolate the engine bolt from the mount and to do that you have to have a sleeve on the bolt and the rubber between that and the mount.
If you only have rubber on the washers as it were, you won’t be able to torque the bolts up, without crushing the rubber into submission and thereby reducing it’s effectiveness to zero.
My Norge is nothing special and I can almost always read the number plate of a following vehicle.

[Huzo]

Interesting idea...I've got the super heavy Throttlemeister bar ends, wouldn't filling the handlebars (assuming it's hollow) make the steering heavy for maneuvering?

No mate.
Because vibrations are high frequency/low amplitude oscillations and are thereby high accelerations of the bar ends, this is where the inertia of the bar ends does it’s work. The mass does not accelerate then stop very readily.
Countersteering...(!) inputs are the complete opposite. The accelerations of the bar ends are very low and the displacement is also small, so the mass in the ends will be close to, if not completely unnoticeable.

[PJPR01]

Ok...some very interesting ideas here...digesting them as I work thru a glass of Cabernet here...appreciate all the tips and tricks here gents!

I'm left thinking that I need to do another round of bolt tightening/tapping to see if anything is slightly loose somewhere...damn this Norge has a lot of bolts to check!

 

[kirby1923]

There is a lot of mickey mouse motions going on between the crankshaft thru the transmission and to the rear drive and as you put miles on the whole mess all sorts of harmonic vibrations come and go as everything wares including the reciprocating parts in the engine.

They (factory ) do a lot of testing to find the best compromise on the NEW machine.

Even though my beemer with the 180 degree V that is in perfect balance except for the small shaking moment has had its bouts w/ strange vibration/harmonic interaction  in the running gear, even maybe a slight variation in compression between the cylinders can cause "things" that go bump on the road.

My beemer used to be dead smooth at 4500 rpm in top but now there is a slight buzz until I'm a bit under that or over... Just like my knees never gave me any pain while jogging but now...

I use the  Throttlemeister bar ends for the throttle lock but they do quell the vibrations on the mirriors at cruise speed.

Without a redesign of the mounting system used on your steed  band aids will most likely result in a worse
condition.

Don't worry, be happy..

FWIW
:-)

[SmithSwede]

Paul, what kind of oil are you running?

Personally, I’d mount a compass and a Burkard Trap on the handlebars and log some data.   Are these bothersome vibes more pronounced when heading southbound?   Away from the sun? 

I can detect increased vibes whenever the oak pollen count exceeds 175 grains per cubed meter on my homebrew Burkard Trap.  Admittedly that’s on a small block.   Dunno about your fancy 1100. 

 

[Huzo]

Even though my beemer with the 180 degree V that is in perfect balance
:-)

.....?

[Kiwi_Roy]

If you ever rode a British twin you will never complain about Guzzi vibes.

[kirby1923]

If you ever rode a British twin you will never complain about Guzzi vibes.

True that!

A lot of weight jumping up and down in formation but...sure sounds good!

:-)

[Lannis]

If you ever rode a British twin you will never complain about Guzzi vibes.

Got three of them right now that I ride.   Lemme tell ya how to fix that so that you can cruise all day at 60 - 65 MPH and not put your hands and feet to sleep.   

1)  A Norton Commando is a British twin, and it's as smooth as any other bike you can buy.   So they're exempted.

2)  For a BSA twin (A65 or A10) there are two things you can do.   

First is electronic ignition.    When you have points, you can never adjust them so that ALL THREE of the Dwell, Gap, and Timing are spot on for both cylinders (dual point Guzzis have this same issue but have better primary balance).   With an EI, the geometry of the trigger plate assures that both sides (wasted spark or not) are firing at the same crank position each time 'round.   

Second is to get your crank dynamically balanced when the engine is rebuilt and sludge trap cleaned.   The last time I did it, the shop charged $150 to balance the crank, and it was worth every penny.

I've done this for my British twins, and all you get is an easy-to-live-with thrum, not a hammering vibration that makes the grips feel like they are 2" in diameter.

Lannis

[John Ulrich]

Norge's have cast handlebars.  Bar end weights are the only option to try. 

[randy yocum]

My 2 valve Norge runs beautifully and has for many years , about the smoothest Guzzi I've ever ridden,if you've got excessive vibration it's got to be in tuning or an engine mount bolt is broken.I do have bar end weights on the handle bars they were on the bike  when I bought it. It's a toss up as the which of my 4 Guzzi's is smoother it's for sure between the Stelvio or the Norge .

[Perazzimx14]

Try filling the handlebars with lead shot or BBs

Or good ole silly-cone caulk!

[Ncdan]

Interesting idea...I've got the super heavy Throttlemeister bar ends, wouldn't filling the handlebars (assuming it's hollow) make the steering heavy for maneuvering?

There is no noticeable difference in the steering between the 3/4” bars and the considerably heavier 28mm bars. I have never personally did it but in years gone by there lots of documentation where lead shot In the hollow bars greatly tamed the vibration in bars on the ole pounder bikes of the past. 

[PJPR01]

Thanks all...I should probably reiterate that there's no vibration issues in the bars at all, I can ride all day with no issues of numbness or handlebar issues, it's just a slight buzzing that I can feel from the engine itself...so I'm back to seeing if I can "fine tune" it even more and keep hunting for any loose connectors or items that seems to pick up the harmonic vibration above 4k pm.

The bike is super smooth, gets great mileage, very balanced, it's just a noticeable (slight) change in engine smoothness above the 4k...and maybe that's as good as it gets.

 

[jacksonracingcomau]

My Norge is nothing special and I can almost always read the number plate of a following vehicle.

Bike may not be but your eyesight is stunning
Reading in mirror I can do stationary but I cannot take me eyes of the road long enough to read a number plate in the mirror when riding.

I used to have “move over you wan#er” in back to front writing on my headlight protector to make it easier for outside lane drivers to understand but they don’t look in the mirror so it didn’t help

[lucky phil]

Has anyone here experimented with placing a thin but hard rubber grommet or washer on the mounting bolts between the frame and the engine on a 2V Norge? 

I'm curious whether that would make the bike any smoother at higher revs and / or would it create any alignment issue with the CARC drive if say the washer was 1/8" thick?

The bike runs great, but there's a slight buzz above 75 mph in top gear that I would love to eliminate, and it's not valves, TPS or Throttle bodies as I've done those multiple times down to the finest level of tuning possible with Guzzidiag.  It's not annoying, I'd just love for it to be as smooth above 4k RPM's as it is below 4K or find whatever else it could be that creates that buzz...mind you, it's not enough to put my hand to sleep or anything.

It's just not that simple rubber mounting an engine period let alone a backyard conversion. Using isolated mounts is a decision taken at the design stage and a LOT of well, science and testing goes into it. If you do what you are suggesting the result will probably be cracked engine and or frame mounts and a degradation in the handling. Engine and frame combinations that are designed to be rigidly mounted basically need to stay that way by and large. The engine is almost always an integral part of the frame rigidity and doing what you suggest would be pretty much like riding with loose/undertorqued engine mount bolts which is where frame and or engine cracking comes from. Better off experimenting with rubber mounting the handlebars or varying the weights in the bars or using solid bars etc.
You can't eliminate all the vibes from the Guzzi engine, its going to vibrate at some point in the rev range.A Ducati twins vibe patch is right around 4000rpm but even though the Guzzi is a 90 deg twin like a Ducati the different crank orientation means the vibes will be felt at a different rpm point. Guzzi went from the traditional 90 deg twin 50% balance factor quite a while back to 52% not to actually make them vibrate less but to make them "feel" like they vibrated less almost certainly due to the crank orientation in the chassis. You can get away with a certain balance factor until you increase the engine size/performance/rpm to a certain point then you might need to modify things balance wise. Thats why you'll generally find most automotive 4 cylinder engine over around 2 litres now have a balance shaft. Over 2 litres the natural secondary imbalance of the engine is getting too much for the average customer.   
The orientation of the engine the way its mounted ( solidly or rubber) and the purpose its going to be used for are all variables in coming to a decision on the exact engine balance factor. You MAY balance a race engine a little differently to a road bike for instance.
There's a hugh amount to get your head around with regards to engine balance factors their effects and consequences and influence on engine mounting.
   

Ciao