Strong vibrations at 3500-4000 rpm

[mikitio]

Hello everyone,

Excuse my English, I am Spanish and I am using Google translator.

My name is Luis and I have a Stelvio 2008 with 43 thousand kilometers.

I would like your help with a problem I have on my bike.

Suffer a strong vibration moving between 3500-4000 rpm, are not the normal vibrations of our engines. These vibrations begin on the handlebars (3500), continue on foot (3800), returning to the handlebar (4000) and then seems to decrease, but if I keep up revolutions I feel the vibration on the feet.

I've tried just about everything I could think of:
- Tighten motor mounting screws, so good both outside and under the fuel tank.

- I'm synchronized cylinders and control valves, so good.

- The tires are in good condition.

- The rear wheel has no strange movement.

- The suspension seems fine.
I put the bike on the center stand, I put 3rd gear and have accelerated to reach 3500-4000rpm and no vibration producien, which means that only happens when the bike is moving or standing with wheels on the ground ( in this situation the vibration is low).

I not know what else I can look.

Well, if someone has suffered these vibrations (much more sensitive than normal) and can help me be very grateful.

Greetings to all.

 

[john zibell]

You have covered the usual cause of throttle body synchronization. I hope you did a TPS reset after you balanced them. Now you need to look at less likely causes. Wheel balance, front wheel bearings, swing arm bearings, head stock bearings. Let us know what you discover.

 

[Trout]

A little test: Ride the bike up to & past the vibration point then pull in the clutch & coast.

Does the vibration change or go away?

If it goes away then rev the engine back up to the vibration RPM & see if it comes back.

If it come back it is most likely engine problems.

If the vibration stays with clutch pulled in then it is chassis or drive line.

 

[Android]

Wheel balance can shake the bars and phase in and out, old tires are especially likely to be out of balance

 

[canuck1969]

What gear are you feeling the vibrations in. Is it all the gears, or say 5,6 when you are going up a hill or trying to accelerate quickly. That engine does not like to be lugged. It won't actually lug like other bikes as is plenty of torque to pull you through, but you will feel as vibration.

Putting it on the stand and spinning the tire won't tell you much as the engine is not under a load although it is good to hear that you did not feel any on the stand.

When you feel it, drop a gear. Does the vibration go away or get better for the same RPM?

That RPM range is very typical for vibration with these engines. Normally after a lengthy break in goes away but your mileage should be more than enough.

Do you have NTX style crashbar that mount to the engine and the rear sub frame. If so, try tightening those bolts. Those have also been shown to cause vibration if loose.

 

[Luciano_MG_V7Special]

I have the same exact issue with my 2014 V7 Special. I feel it prominently on 3rd and 4th gear around the same rev range. I started to notice this vibration after I redlined the engine on 2nd gear. Not sure if that would have anything to do with it, but I am starting to think maybe it's an engine problem..

 

[Wisconsin v7 Racer]

I had a vibration on mine at 3000 RPM and when I adjusted the clutch it seemed to solve most of it.

 

[Trout]

I have the same exact issue with my 2014 V7 Special. I feel it prominently on 3rd and 4th gear around the same rev range. I started to notice this vibration after I redlined the engine on 2nd gear. Not sure if that would have anything to do with it, but I am starting to think maybe it's an engine problem..

Hitting red line may have just loosened some things up. If you have crash bars check the mounting bolts. If not then just go over the whole machine & snug things up.

Guzzi's, like other machines have a break in period but unlike other machines a Guzzi has a long one, it may take up to 20,000 miles (twenty thousand!) to become fully settled in. During that time it is a real good idea to keep an eye on all the nuts & bolts & do all the factory recommended services including valve adjustments.

Guzzi's are very much a "hands on" bike & most of us that have ridden them for years have found great enjoyment in maintaining them, it really helps to build an appreciation for a fine machine.

 

[Luciano_MG_V7Special]

Thank you for that info Trout!