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

[FreyZI]

Chuck, did you pose for the P-O? Story there?

[Chris Wilson]

Twin plug the head and change the advance will make it smoother.

[docc]

2 hours ago, Chris Wilson said:

Twin plug the head and change the advance will make it smoother.

Change the advance for the twin plug, or change the advance in addition to the twin plug?

hange the advance how (and where)?

[Chris Wilson]

Hi Docc, 

There are already numerous threads on this site about this but they all say to retard the ignition point when adding a second plug but surely you would advance it because the flame path is shorter and now symmetrical?

No expert on where to advance but to me it has to be mapped preserving idle and keeping watch on pre-ignition. 

Got the feeling that I am going to learn something here!

Chris.

[docc]

20 minutes ago, Chris Wilson said:

No expert on where to advance but to me it has to be mapped preserving idle and keeping watch on pre-ignition. 

Got the feeling that I am going to learn something here!

+1 on that, buddy!

[Chuck]

On 1/11/2022 at 5:46 PM, FreyZI said:

Chuck, did you pose for the P-O? Story there?

Story? I was going to the Ohio rally, when I was passed by two Break My Wallets with all kinds of anti detection stuff like I was sitting still. I thought "oh boy, rabbits," and stayed behind them just far enough to barely keep them in sight. We flew across Indiana and well into Ohio at go straight to jail speeds, when I came to a corner and didn't see them. "Uh oh." Got off the throttle and was only doing 70 when I saw the trooper.

Naturally, he lit me up, and I was stopping before he even made the highway. It was the most enjoyable traffic stop I'd ever had, though. He was friendly and we literally shot the shit for a half hour. Didn't make me unpack the bike to show proof if insurance. Nice guy that got a grin that he was giving a speeding ticket to an old guy on an Italian motorcycle.

I asked him to take the picture.

The reason for the shit eating grin?? He didn't get me about 30 seconds before.. I didn't mention that, though.

[Pressureangle]

14 hours ago, Chris Wilson said:

Hi Docc, 

There are already numerous threads on this site about this but they all say to retard the ignition point when adding a second plug but surely you would advance it because the flame path is shorter and now symmetrical?

No expert on where to advance but to me it has to be mapped preserving idle and keeping watch on pre-ignition. 

Got the feeling that I am going to learn something here!

Chris.

Simple, really once it's pointed out. The engine has a crankshaft angle at which peak cylinder pressure has the greatest effect (about 20* ATC iirc) so it's not the ignition that matters, but how quickly peak cylinder pressure is reached. Ignition timing is moved to accommodate the rate of burn to get the peak where it does the most work.

[PJPR01]

2 hours ago, Chuck said:

The reason for the shit eating grin?? He didn't get me about 30 seconds before.. I didn't mention that, though.

Need to know basis only...why divulge unnecessary incriminating info!  You look happy, that's the most important!  Nothing like running above triple digits...smooth as silk!

[Chris Wilson]

3 hours ago, Pressureangle said:

Simple, really once it's pointed out. The engine has a crankshaft angle at which peak cylinder pressure has the greatest effect (about 20* ATC iirc) so it's not the ignition that matters, but how quickly peak cylinder pressure is reached. Ignition timing is moved to accommodate the rate of burn to get the peak where it does the most work.

Yep, got it!

Don't know why I didn't before.

Thanks, Chris.

[VtwinStorm]

13 hours ago, PJPR01 said:

Need to know basis only...why divulge unnecessary incriminating info!  You look happy, that's the most important!  Nothing like running above triple digits...smooth as silk!

I will test this on a safe and legal track day. 😁

[al_roethlisberger]

On 12/31/2021 at 10:33 AM, 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!) . . .

 

Agreed! I've been using these grips on various motorcycles for 20 years.  They have a great feel, tame vibrations, and have great grip.

 

I also filled my factory "clip on" bars with lead shot and silicone, and have the heavy Throttlemeisters.  

 

That all seemed to help, but it's still a twin

 

 

[Chuck]

^^^^ Pro Grips gel and lead shot plus Napoleons is what I had on the Mighty Scura. Worked pretty well, but yes you could feel a little ticking from that V twin. That's a good thing.

[motoguzznix]

Hi all

Some of the red frame V11s had an issue with severe engine vibrations. There is no way to cure that with foam or silicone grips or bar end weights. 

I remember a road test in an italian motorcycle magazine by Alan Cathcart with a very early V11 that mentioned also the engine vibrations. 

My very much beloved black V11 from 2000 was also one of the bikes affected. I was happy with the bike until I changed bike with a friend of mine driving a Lemans3. He was shocked by the amount of vibrations generated by the engine. Me too experienced how smooth the old Lemans engine was running. 

The red frame V11s suffered of two factory rework issues: one related to the gearbox, the other to the conrods. For my chassis number only the gearox rework was listed and carried out by my fellow dealer. I suggest my bike suffered also the rod issue. Guzzi mentioned the rods were prone to crack on bikes frequently revved near the engine rpm limit. 

My conclusion was the rods on the affected bikes were too heavy and so the engine balance was out of spec. For my bike there was nothing to be had from Guzzi, so I decided to balance the crankshaft myself. At 9k km I dismounted the engine from the frame and teared it down to bits. I weighed all the parts necessary, calculated the master weight and put it on the crank pin using lead sheet stripes. The balancing was carried out only statically on a balancer very similar to tools used for tire balancing. My crankshaft needed removing of material mainly in the area of the crank pin.

When the engine was completed and reinstalled, the running behavior was absolutely different: The severe vibrations were gone, the engine was almost smooth as the LM3 engine.

 

[Joe]

For what its worth as a mere mortal to the experts on this forum. 

I owned a 2001 Silver V11 Sport new that I later added a Fast by Ferracci drop in pistons, FBF Power Commander w a custom map made to make peak horsepower, lastly FBF carbon exhausts. What Mike Wells & I created was one of the coolest deep toned 2v Big Block Guzzi's ever.  We also created a vibration machine that even with Throttle Meister heavy bar end weights couldn't resolve, leaving you with numbness on demand.

Many years later, my new to me, low mileage V11 Sport Rosso Mandello is running a custom map (idle is higher), everything balanced to spec with stock bar ends, no power commander. Riding to the 22 Spine Raid last year, rarely did it create enough vibrations in the seat or the hand grips to create the same sensation as the FBF Silver V11 Sport, remember I'm 20 years older. 

*So there really is a sweet spot on these bikes as far as tuning is concerned to make them more comfortable, again devoid of the technical data supplied by the elite mechanics on the Forum.

[mikev]

Last Fall I purchased some gel grips from revzilla someone here recommended, which I'm going to put on my v11 when it warms up a little more around here.

I am tempted to riding today since its above 45 ... barely.  But the roads are wet and salty.  

What's the deal with lead shot? How much of it is needed and how does one install it within the bar ends?