2007 FZ6 Vibrations

[Jlieb1284]

I know there are alot of posts on this subject but I haven't found one that quite fits whats going on with my bike.

Bought a 2007 FZ6 brand new and just rolled over 36k on it. The last 2k its developed a significant vibration that was not there before. It vibrates at an idle (1200-1500 rpms), stops until you hit just over 6k, then starts again. The vibration shakes the entire front end of the bike.

The vibration is a feel and not a sound, not getting any new buzzes. When hitting 70-75 in 6th the mirrors are shaking bad enough I can't see anything behind me. Up until the last 2k the mirrors didn't shake until around 95-100. Going down the freeway hitting 80, pulling in the clutch and letting the rpms drop the bike goes completly smooth while maintaining that speed. While coasting you can play with the throttle and the vibrations start at the same time (just above 6k).

I've taken it into the dealer and they found a loose motor mount but that didn't fix anything. The mechanic took it for another ride and said I wasn't crazy, the vibration is there and its just odd. Listening to the bike everything sounds normal and he was amazed and how well it was running.

Since this has started I've changed the spark plugs (no change), realigned the rear tire/chain (no change) and combed the bike for loose nuts/bolts (no change).

Both me and the dealer are at a loss of what to do. This vibration has me thinking of selling the bike (yes its that annoying). Any advice would be greatly appreciated! Thankyou in advance.

 

[TownsendsFJR1300]

How did the old plugs look?

A compression test as well as putting a lazer temp gun pointed at each header may indicate if you have a cylinder not firing.

Finalimpact has found the ignition wires, where they screw into the caps sometimes come loose causing an arc (bad contact and misfiring). Shortening the wires just slightly and re-installing (spinning in) the caps should take care of that.

Something else and cheap to try, a couple of tank fulls of Chevron techtron, a fuel system cleaner. If you got some crap in the injectors, a valve not seating fully, Tectron should help.

Speaking if valves, have you had the clearances checked within the last 25,000 miles?

A valve not fully seating will cause all kinds of problems as well as damage if not addressed, adjusted). They tend to tighten up with age mileage as the valves seat..


Also, if you could post a video with audio of the bike running may help in diagnosing if possible...

 

[Jlieb1284]

The plugs looked just fine when they came out, they only had about 8k on them but I replaced them anyway. I checked each spark plug wire as well, no damage, still in good condition and no odd "wiggles".

I normally run 91 Shell gas and haven't put through any system cleaner in a good 10k miles, will try that.

Valves were done at 22k, so 14k or so since that's been opened up. That was my next thing to check unless anyone could come up with something simpler.

One thing I forgot to mention was my exhaust, during the last 2k miles since the vibration has started, it has started to tick when the bike is hot and turned off. It never did that for the first 34k.

I wish I could post a video but don't have anything to shoot one, it would all be visual though as there is no apparent "sound" being caused by this vibration.

 

[TownsendsFJR1300]

The plugs looked just fine when they came out, they only had about 8k on them but I replaced them anyway. I checked each spark plug wire as well, no damage, still in good condition and no odd "wiggles".

I normally run 91 Shell gas and haven't put through any system cleaner in a good 10k miles, will try that.

Valves were done at 22k, so 14k or so since that's been opened up. That was my next thing to check unless anyone could come up with something simpler.

One thing I forgot to mention was my exhaust, during the last 2k miles since the vibration has started, it has started to tick when the bike is hot and turned off. It never did that for the first 34k.

I wish I could post a video but don't have anything to shoot one, it would all be visual though as there is no apparent "sound" being caused by this vibration.

The ticking is usually from a heated part (usually exhaust) cooling down. If it never done this before (last summer too) maybe something to look at. I'd borrow or get a temp sensor gun on those headers and get some #'s.

Sounds like you also use most of the RPM range. Do you know what the spec's were of the valves when last checked? Were they in the middle, JUST INSIDE SPEC's, etc? Yes, its only 14K miles since the last check, but if they were borderline then, they could be out now....

A cheap (but not nearly accurate) way to check the heat on header, especially since it vibrates bad at idle: get a small syringe(or similar) and squirt just a tiny bit of water at the top of the header (where it bends) once warmed up.

You want to look to see if one header in particular is NOT GETTING AS HOT as the others. The water won't sizzle off as quick and let you know what cylinder is acting up (or valves, injector, etc) for that cylinder.

Good luck and please post your results..

 

[FinalImpact]

Finalimpact has found the ignition wires, where they screw into the caps sometimes come loose

True, if the caps screw does not hit the core of the wire the cap comes loose = TRUE

causing an arc (bad contact and misfiring).

= FALSE! It does NOT cause a Misfire, nor does it cause an arc over!
It DOES cause a bad vibration across the entire RPM band.

Shortening the wires just slightly and re-installing (spinning in) the caps should take care of that.

= True, but care must be taken or it will repeat itself. The wire strand core must be feathered into a circle BEFORE the cap Eis screwed back down.

ALSO: Measure the plug cap while detached. It must measure 10,000 ohms +/- 500 ohms.
Measure the spark plug from the electrode to the cap area. it should be 5000 ohms. If more, REPLACE IT!

Set the GAP: NGK ships it at 0.032. Spec for our bike is 0.028" MAX. If you suspect ignition issues - drop the Gap to 0.026 or 0.024"!

Lastly, I know no one wants to repeat their work, but if you really want to get to the bottom of this; I suggest you look at each of these items again. if you PAID to have it looked at, I'll bet money THESE DETAILS were Missed!
The ignition on these bikes are weak and can be compromised leading to vibrations which are not so bad as to be Misfires! Mine did NOT misfire ever, but it did have a vibration.

Also, I would ditch the CR9EK in favor of the CR9E single ground strap plug with a gap of 0.026" and open it if it can handle it.

See thread: http://www.600riders.com/forum/fz6-technical/48874-cure-bad-vibrations-spark-plug-caps.html

 

[FinalImpact]

Adding to above; something that readily gets over looked;

A vacuum leak under the TB!

I don't recall the size but its either 3 or 4 mm. I'd suggest you remove the air box and snug up the bolts holding the TB to the intake. I've found two of our FZ's to have these loose.

The bolt has a positive stop so once tight, it should stay. It doesn't need much torque so reach in and snug it down.

 

[TownsendsFJR1300]

If it does not have a good contact, it will indeed arc and cause a bad contact.

Spraying water or checking the ignition in the dark will often reveal arcing.

If its NOT got a good contact, it will misfire, thus run rough and vibrate. The vibration is telling you something is amiss (pun intended), one leading to the other. If it was smooth, there's obviously nothing wrong (IE, no arcing, no vibration)

You of all should see have seen arcing inbetween the cap and wire if it truely were not satisfactory..

To say an engine, that vibrates more so all of a sudden, is either NOT misfiring, or have another issue is ludicrous...