Name that tune!

[mikeholzer]

On my 1992 FJ (85,000 miles, give or take), I am getting a "buzzing" sound for a half second when coming from a stop in low gear. To describe it better, it sounds like a chain dragging internally, but only under load. If I rev the motor higher as I'm letting out the clutch, there is no noise, but I'm not always interested in covering that much distance that fast, especially coming off a light in city traffic.

I guess that my concern is that it is a cam chain issue. I know that way back in the early 80's, the Yamaha XS1100 had a terminal cam chain problem (the old man had one in the late 80's; it got expensive real quick!). I've never heard of anything of the sort on these 1200's, but I have to say that it really sounds like a chain dragging. It certainly sounds like it's coming from the engine, and not the gearbox or the drive chain. I've scoured the manual looking for information regarding the cam chain tensioner; is there an adjustment here? Do I need to take it out and clean it or replace it? One of my old Hondas had you let the bike idle, and you loosened a nut on the front of the motor and centrifugal force brought the chain into tension (this, coming from the company who'd have you periodically re-tension the timing belt on your Civic or Accord). Are we playing a similar game on the FJ?

Regardless, I'm wondering if any of you may have a little insight into what could be producing this noise (which I cannot demonstrate for you ). The pictures in the manual are tough to sort through, but I see that the starter drive is also chain driven; and is that a big chain running between the crankshaft and the clutch? I'm not riding a Harley here, am I? Short of tearing this thing down (very undesireable today), I'm at a loss...

[racerman_27410]

if you lug the engine on take off a rattle-ing sound is not unusual.... these engines protest lugging by making noise....a very agricultural noise.....

1000RPM idle/ take off should not produce noise......whereas a 700rpm take off would.


KOokaloo!

[mikeholzer]

Agricultural is a good word to describe it, Frank. Sounds a little like my Uncle's 1941 McCormick M coming off idle with the baler attached.

My idle is set just a touch over 1000, but honestly, that is info via the tach. I might just hook up my timing light and get a tach reading from it. I'm now wondering - after reading some of the carb posts - if maybe I'm falling a little flat right off idle due to a carburetor issue. The motor really seems to bog down unless I give the throttle a bit of a hefty twist (not huge, mind you, but maybe a little agressive). Maybe too little fuel is dropping my base idle and creating a near-stall condition, hence the noise. Whatever, I wish you guys could hear it.

Also, I've got what appears to be the factory header and Yoshimura pipes; the baffles in those pipes are shot, but I just scored 4 repackings off of eBay for $7.50 each. Perhaps some of this off-idle performance will improve with a little pressure from the pipes. At least it will be a little quieter when I leave in the morning; Momma has been bitching about the 5:50 A.M. FJ wake-up call.

[Dan Filetti]

Make certain it's not the down-pipes.  I've read where the inner walls of the down -pipes can apparently rust free and rattle @ certain RPM's, producing one hell of a racket, that sound +/- worse than it actually is..

Possibly a long shot.

Dan 

[rktmanfj]

Make certain it's not the down-pipes.  I've read where the inner walls of the down -pipes can apparently rust free and rattle @ certain RPM's, producing one hell of a racket, that sound +/- worse than it actually is..

Possibly a long shot.

Dan 

The 1st gen had that problem, later models have single wall pipes.

Randy T
Indy

[scapello]

I have the same sound and also believe it is the slack in the cam chain. It only does it when the engine is near stall with little throttle on take-off (it literally sounds like you are dragging a chain). I have been reluctant so far to adjust it since one of the previous owners made a note that he had replaced the adjuster with a manual one. Mine looks nothing like this one:
http://fjowners.com/gallery/181_07_05_09_10_53_25.jpeg

Mine is just a screw with a counter nut that looks like this one:

http://shop.thumpertalk.com/ProductDetails.asp?ProductCode=ENG%5FTT%5FMCCT1&Show=ExtInfo

Can someone confirm that the stock type looks like type one? Based on that you should not need manual adjustment since it is spring loaded, correct? The note in my manual (from the guy that put in the manual) states that engine noise was greatly reduced after he installed the manual one, maybe that would be an option for you.

[racerman_27410]

its not the cam chain making the noise... its the starter chain and clutch basket rattleing

normal noises for the FJ when being lugged

nothing to worry about.

KOokaloo!

[scapello]

I hope you are right but since mine is manual I will try to adjust it to see if it needed it. I might have a way to record my sound with reasonable quality and Mike can let us know if that is it.

How would one insert a sound file?

[TRoy]

+1 on the starter chain.  It has no tensioner. Only a shoe slider. A new one will lessen the agriculture. You'll have to R&R the crank.

Like Frank said, keep the revs up & don't worry about it 

[mikeholzer]

+1 on the starter chain.  It has no tensioner. Only a shoe slider. A new one will lessen the agriculture. You'll have to R&R the crank.

F*** R&R the crank! For today, I'd really rather ride. I have an acquaintance (more a friend-of-a-friend) who campaigns three Legends cars. He's pretty up to speed on these motors, but not on a bike, and low throttle starts are unfamiliar to him. However, he knows the motor, and maybe I'll allow a little surgery over the winter.

Would a sloppy starter chain cause the starter motor to sometimes crank, then not crank but instead issue the standard un-loaded high speed DC electric motor noise (ZzzZZzzZZzZZzz!). That only happens occasionally, and I haven't been super worried about it.

Last, thanks a lot for all of your input. You're the best invisible friends that a guy could ever have.

[Arnie]

Mike,

If your starter chain is horribly sloppy and the sprockets extremely worn, I guess it could just dance over the sprocket teeth and give you a whirring noise.  I'd think it more likely that the starter clutch would be slipping - but I haven't heard of anyone complain of this.

Cheers,
Arnie

[rktmanfj]

+1 on the starter chain.  It has no tensioner. Only a shoe slider. A new one will lessen the agriculture. You'll have to R&R the crank.

F*** R&R the crank! For today, I'd really rather ride. I have an acquaintance (more a friend-of-a-friend) who campaigns three Legends cars. He's pretty up to speed on these motors, but not on a bike, and low throttle starts are unfamiliar to him. However, he knows the motor, and maybe I'll allow a little surgery over the winter.

Would a sloppy starter chain cause the starter motor to sometimes crank, then not crank but instead issue the standard un-loaded high speed DC electric motor noise (ZzzZZzzZZzZZzz!). That only happens occasionally, and I haven't been super worried about it.

Last, thanks a lot for all of your input. You're the best invisible friends that a guy could ever have.

What kind of oil are you using?

Seems like someone posted once that synth caused their starter clutch to slip.

Changing back to dino cured it.

Randy T
Indy

[mikeholzer]

I'm running Golden Spectro Semi-Syn 20W-50. The previous owner swore that that is what he's ran in it since around 7,000 miles, so I figured I'd stick with what's been in there. Next time around, I'm switching down to 10W-40, but I was planning to continue with the Golden Spectro. I'm not sure that after all of this time that it would be good to go back to the "organic" formula.

Fortunately, the starter issue is EXTRMELY sporadic; maybe once every 20 or so starts. It never does it more than once, so it's not a huge concern for today, but something I'm keeping on my mind for the future.

I've been keeping the revs up a bit higher coming off the line as I've been riding today, and I have to say that the noise is significantly better. I guess I learn a little bit more about my boy every day.

[Zwartie]

This problem sounds somewhat familiar. I had a rattle like that a few years ago on my '92 and I thought there was a major engine problem. Of course it happened during a bike trip. Stopped by the Yamaha dealership in Watkins Glen, NY and their mechanic checked it out - he had absolutely no idea what was causing the sound. It wasn't until later that day (when the engine was cool) that I decided to check the header pipes and sure enough, one of them was just loose enough to rattle around. Tightened up the (12mm?) nuts and it was good to go. It did it one time since then and I retightened the nuts again.

Hope that helps!

Ben Zwart
London, ON

[xt550]

It may be to low octane fuel, but it's usual a ticking sound like aluminum cooling.
In Sweden it's called "spikar" im not sure what you call it , ignition before top dead center(earlier than supposed to).
Not that dangerous if it's only momentarily but prolonged can make serious damage.