Return of the Buzz

[motochick]

Hey all,

After installing a PCIII and doing a TB sync months ago the terrible 4k buzz virtually disappeared (with the stocker map, I like it better than the "smoothness" map which still had a bit of buzz). Today I went for a short ride and its back! Worse than ever. The bike runs fine, idles fine, still accelerates the same but on the hwy when I get around 4k its so bad through the pegs that my feet get numb.

Any reason why it would suddenly return? I haven't rode it for 5 days and the temperature and humidity have gone up the past day.

thanks,

jen

 

[PA1195]

Hey all,After installing a PCIII and doing a TB sync months ago the terrible 4k buzz virtually disappeared (with the stocker map, I like it better than the "smoothness" map which still had a bit of buzz). Today I went for a short ride and its back! Worse than ever. The bike runs fine, idles fine, still accelerates the same but on the hwy when I get around 4k its so bad through the pegs that my feet get numb.

Any reason why it would suddenly return? I haven't rode it for 5 days and the temperature and humidity have gone up the past day.

thanks,

jen

Hello Jen. I'm not the expert on de-buzzing the FJR. Many here have done lots more in that regards. But with my two previous FJR's, I was able to minimize the "4K buzz" by doing two things. First was ensuring that the motor mounts were properly torqued. The second was doing a throttle body plate synch - not the typical idle air crew adjustment, but adjust the three inter-throttle body adjusting screws. It's a procedure not normally recommended by Yamaha. But if the engine's buzzy, why not see if it helps? It can all easily be returned to the Factory specs if no change is noted and notes are taken.

The latter involves running the engine up to 4K in neutral and adjusting the three throttle shaft screws if the individual throttle body vacuum is not close in value under both acceleration and at a steady cruise RPM. Equalize throttle bodies #3 to 4, #1 to 2, and last #1 and 2 to 3 and 4. However, it's best to run the bike on the road under load with a manometer attached to get a true indication of any differences >1cm Hg. It involves more fiddling than most are willing to do.

All the above assume that the ignition parts and fuel metering components are functioning properly to begin with. Check them first, look for any error codes and proper sensor/component diagnostic parameters as shown in the Service Manual, then do the TBS as required would be my advice. Or just wait until the weather changes.

Gary in Fairbanks

 

[motochick]

Hi Gary,

Thanks for the tips. What is the proper procedure for the engine mount bolts? Do you just remove the plastic and check the torque of each bolt? Or should I loosen all of them at once and retorque?

Thanks again,

Jen

 

[Bustanut joker]

Ummm. :blush2: Man I could really de-rail this one ..

But as I've yet to see where your humor runs, I'll just slink away

:jester:

 

[FJRay]

Ummm. :blush2: Man I could really de-rail this one ..
But as I've yet to see where your humor runs, I'll just slink away

:jester:

Chicken Shit.

 

[motochick]

derail it, fuck it...that's what these forums are for right? To make an idiot out of someone who probably is an idiot(I'm clueless)...

 

[SockMonkey]

derail it, fuck it...that's what these forums are for right? To make an idiot out of someone who probably is an idiot(I'm clueless)...

Well if you insist...

Any reason why it would suddenly return?

Because it thinks you're, uh, "lonely"..?

 

[wfooshee]

Couldn't hurt to get another TBS after that amount of time. Also, you mighta picked up something in your fuel sometime. Last year I ran the bike as dry as I ever had, and it ran for shit for several days after, probably having picked up some crud that usually lives low in the tank. A few tanks with some Seafoam and it either got better or I got used to it. Not sure which. :huh:

 

[chrisflock]

Is the problem that the bike only vibrates at 4k rpm, or that the bike vibrates through the pegs?

If it's something that has come on very suddenly, it could be any number of things. Are there any other symptoms? Reduced fuel mileage, any sign of running rich or lean? I'm assume nothing else has been changed, like suspension adjustment or anything?

 

[PA1195]

Hi Gary,Thanks for the tips. What is the proper procedure for the engine mount bolts? Do you just remove the plastic and check the torque of each bolt? Or should I loosen all of them at once and retorque?

Thanks again,

Jen

Hi Jen. The torque check I was referring to and think is most important would be for the two bolts that are removed if frame sliders are installed - #'s 10 (right side) and 13 (left, tighten this first) @ 35 ft.lb - they are those internal hex head bolts exposed in the air slots on either side of the plastic side body panels that attach the upper rear engine to the silver upper frame. You may not have sliders, but if you do, the bolt torque can creep depending upon slider design. I don't have enough experience to say if the other engine/frame fasteners are prone to losing torque over time. A couple of bikes I've owned - Suzuki and Kawasaki - wanted to see them all tight or the buzz started right now and walked around the RPM range some depending upon which one loosened from gradual wear in the bike's frame.

The advice of an idle TBS would be a good place to check and start, as would adding some Techron or Seafoam gas elixir to maybe clean some crud, if it's the really cause of a broad band vibration. If the buzz persists at a consistent but limited RPM regardless of gear or speed, then I'd pursue the throttle plate synch I mentioned earlier. Yamaha sets the three throttle shaft adjustments before engine assembly, but that can't compensate for changes in individual cylinder volumetric flow and efficiency throughout the engine's life. It works for me, is pretty easy to do if you have access to a manometer and patience. But then I'm fairly particular about vibration that comes and goes, as I've had it do bad in aircraft and other powerplants.

Let us know what develops. Maybe it'll just fix itself as these things sometimes do.

Gary in Fairbanks

 

[RadioHowie]

Last year I ran the bike as dry as I ever had, and it ran for shit for several days after, probably having picked up some crud that usually lives low in the tank.

Walt,

I love ya, guy, in the normal Forum-Non-Ghey kinda way, but you MUST know the Feej's fuel pickup is at the bottom of the tank, right?

Any "crud" in there is gonna be sucked up and burned the first time you crank it after it's sat unused for a while...even a SHORT while, 'cause any "crud" heavy enough to settle to the bottom is gonna get sucked in whether or not the tank is full or not.

Not to say one can't pick up some crappy gas on your travels, but running the fuel dead down to the bottom of the tank won't make a lick of difference, since the pump draws from the bottom of the tank all the time.

The only time this could possibly make a difference, i.e., running it "dry", is if the suspected "crud" is floating on top of the gas and isn't available to the pump until you run it nearly dry.

 

[black mamba]

Not that it is really a help to you in this case, but the " visiting buzz " issue with my '05 has been the most perplexing issue I've ever experienced during ownership of nine different bikes. I've tried ALL the usual tricks to deal with the situation. Some days....it may actually last for weeks....the bike is totally lacking in buzz. I can get on it the very next morning and HOLY SHIT....I now own a virtual buzz monster. Nobody I've ever talked with can explain this split personality. I've learned to live with it.

 

[motochick]

Yeah I think you can delete this thread or add it to the NERPT category.

I thought I fixed the problem as it ran smooth as a jet engine for months. I'm just going to do what the experts recommend in this thread (and many others) or just live with it. It will never be perfect because I know all bikes have a bit of vibration (my SV1000 was lower frequency, but less of the numbing buzziness).

jen

 

[FJRmogul]

I would try downloading the map into the PCIII again.

 

[exskibum]

THAT is one weird problem (esp. since it seems to be intermittent). Not saying you aren't experiencing exactly what you describe, but I've never had a problem with buzziness on my '05. OTOH, since I once owned a '69 BSA 650 Thunderbolt that used to put my (then young) fingers, hands and forearms to sleep, maybe I was inoculated against high frequency vibration. That bike was a REAL treat on a 400 mile trip, especially since I chopped it, chromed everything, etc. -- pure comfort borne of stupidity and that parallel twin cylinder engine.

 

[NMRoadRunner]

I can't help because my bike runs the smoothest at 4000 to 4500 RPM. Thats it's "happy spot" 70 to 80 MPH!

 

[Bustanut joker]

Walt,
I love ya, guy, in the normal Forum-Non-Ghey kinda way.

You Sir..... Are a Bald faced liar. I've hacked into your work computer .... h34r:

Disgusting! B)

:jester: