FZ6 trouble...

[Kyrider7]

Hey everyone. I am having some trouble with my bike and needing some advice. First, I bought it a year ago from a 70 year-old gentleman. It is a 2007 FZ6 with 11k miles on the clock (1500 by me). It has a two brothers exhaust, everything else is stock.

Today when I was riding, all of a sudden I lost a significant portion of power, serious vibrations started, and it sounded like a cylinder was misfiring (sounded closer to a dirt bike than a 4-cylinder). Turns out the cap was loose on spark plug 4. Refitting it tighter did not solve the problem, and I have no idea how it came loose in the first place.

I replaced all 4 spark plugs and saw a big improvement. bike runs smooth and sounds smooth. However, rolling on the throttle off idle it now sputters for a second or two before taking off. Also, in every gear except 1st there is power loss once I reach 10k RPM's (it still runs and everything but will NOT accelerate until I shift up to drop the RPM's). I have never had either of these two problems until today.

Other possibly useful info…..

For the past month or two I have noticed an odd burning smell when parking the bike after a ride. It is not the headers and it is not like burning leaves or wood. It COULD be oil..but nothing is leaking. The bike is not overheating when running. The smell is coming from the rear part of the engine. It is strongest a little further back from where you add oil, deep "in" the bike.. somewhere hard to see or reach. I haven't noticed any smoke. But the smell is very strong. It stinks up the whole basement.

Also, when I first turn on the key, the fuel pump does its thing but half way through it sometimes makes an odd spewing sound. This has been going on almost since I had the bike, but i haven't thought anything of it until now.

The bike was at the local yamaha dealer for a tune-up, oil change, and new tires a couple months ago and everything checked out fine.

 

[FinalImpact]

Hi and perhaps a 2nd welcome to the forum!

The oil smell and all that, if its not leaking, not sure what to say other than you're primary issue **MAYBE**related.

So its sounds like you solved the plug issue and I hope you set the gap to the Yamaha spec and not the out of the box spec. That said, take a look at this link and read up on spark plugs and the cap. There are some helpful details in there. http://www.600riders.com/forum/fz6-...tion-cure-bad-vibrations-spark-plug-caps.html

IMO its sounds like you're running out of fuel. Because of the low miles on the bike and its age, its good candidate to have a rusty tank. In this case the condition doesn't show itself until heavy load.

In short; if fuel demand is impaired under load it runs lean. When it runs lean the exhaust gets VERY hot as does the whole engine. This may be the cooking smell AND the lack of power. My engine runs from 175 - 195F and for the most part I can place my hand on the case. I won't be holding it there long but its NOT hotter than the radiator itself. So, if by chance you compare the engine case to the radiator and find the case is real hot (are your headers turning blue) these all indicate a lack of fuel.

Bottom line: if enough things add up, pull the fuel pump and take it apart to clean the fuel strainer. However, if it ingested enough debris, it may not be able to hold pressure or it may be leaking internally at the pressure regulator.
Take a look at this thread to resolve this issue. Read it and see what applies if any. I would advice NOT going up to high RPM wise as it could be damaging...

Does it ever Ping or detonate when you take off from a stop? That would be another clue it lean and hot. 2nd post here: http://www.600riders.com/forum/fz6-...mpact-trouble-shooting-maintenance-guide.html

 

[Kyrider7]

Thanks for the quick reply!

The gap on the plugs was set to Yamaha spec before I put them in!

I'll have to wait till I ride again to check the temp of the actual case. The temp on the gauge normally reads about 170 unless in town. Then the radiator fan kicks on and cools it down whenever it gets over 210. I suppose if that temp reading is from the radiator, then the actual engine could still be overheating. Also, the headers aren't blueing; they have a nice golden color to them.

However, I didn't really think it is running lean because the exhaust smells very rich (fuel smell). Is this correct? (I always just attributed the smell to having the two bros exhaust without any fuel mapper.) Although now that I think about it.. it could smell rich at idle and still run lean under significant load. The spewing from the fuel pump when I turn on the key certainly would seem to indicate something funny with the fueling too.

Its starting to sound like I need to take the tank off and have a look at everything.

Would a fueling issue cause an abrupt loss of power specifically at 10k RPM's, or should it be more gradual?

Again, thanks for the help!

 

[FinalImpact]

Thanks for the quick reply!

The gap on the plugs was set to Yamaha spec before I put them in!

I'll have to wait till I ride again to check the temp of the actual case. The temp on the gauge normally reads about 170 unless in town. Then the radiator fan kicks on and cools it down whenever it gets over 210. I suppose if that temp reading is from the radiator, then the actual engine could still be overheating. Also, the headers aren't blueing; they have a nice golden color to them.

However, I didn't really think it is running lean because the exhaust smells very rich (fuel smell). Is this correct? (I always just attributed the smell to having the two bros exhaust without any fuel mapper.) Although now that I think about it.. it could smell rich at idle and still run lean under significant load. The spewing from the fuel pump when I turn on the key certainly would seem to indicate something funny with the fueling too.

Its starting to sound like I need to take the tank off and have a look at everything.

Would a fueling issue cause an abrupt loss of power specifically at 10k RPM's, or should it be more gradual?

Again, thanks for the help!

If you could swing an audio/video upload that would really help. soundcloud is great for a quick audio upload.

Does it still have the mid catp-pipe? Or is it a straight pipe? And no aftermarket fuel controller??

To your point, yes, it could be fat at idle and run lean under heavy fuel demand. Would it be a direct chop at 10k, I suspect not. More of a fade. Like you open the throttle more, it makes a different sound, but you either maintain or loose speed/RPM and not gain.
Perhaps after a run of hitting the dead area and doing a quick stop and take off, if the engine is real hot it will ping on regular 87 octane pump gas.

Have you ever jumped started it from car? Anymore history? Any chance its had a few batteries in its life?

 

[Kyrider7]

I have never jump started it, but I cannot speak for the previous owner. The mid cat-pipe is still on it. There is no aftermarket fuel controller. The man I purchased the bike from said he got too good of a deal to pass up on the two bros exhaust, so he just put it on. I looked into getting a Power Commander, but from what I could tell, not having one should not be causing any major problems. It hasn't for the past 1500 miles anyways.

I looked under the tank, and it appears the fuel pump is not screwed up flush against the tank.. The man I bought it from said he never had it out so I'm not sure what the deal is. It is not leaking at all though. I took a few pics of it so you can see.That definitely needs to be fixed, but it doesn't look like anything recent that would cause a sudden change. While I was at it, I also snapped a few pics of the headers.

I really feel like some actually happened. I have never had any issue until the spark plug incident. Once I fixed that, it started running fine but the top end power is completely gone past 10K RPM's, and it sputters for just a bit rolling on the throttle off of idle. Night and day difference.

Here is a link to a recording of the engine. First 30 seconds is on shifter side, then it abruptly changes to clutch side (I paused it and switched sides). I moved my phone around a lot as I made the recording trying to pick up as many different sounds as possible, so theres a pretty wide variety. Towards the end I gave it a few revs. It sounds normal to me, but I'm no mechanic.

https://soundcloud.com/user127689/engine-recording

Thanks again!

Edit: The pic of the fuel pump is upside down.. It uploaded that way for some reason. It still gets the point across.

 

[Kyrider7]

Also, one more thing. Is it possible for the engine to be running hot but the coolant still show a normal temp (i.e. 175 or so)? If not, then the bike is definitely not running hot. Because according to the gauge, it has never gotten too far over 210.

 

[TownsendsFJR1300]

The sound clip at idle doesn't sound bad, with the slight rev's, it sounds somewhat sluggish revving.

Agreed, possibly fuel related.

We just had another member with a really bad bog. A bottle of Chevron Techtron(fuel system cleaner) in the tank fixed the issue.

BTW, I found out the makers of Techtron are the same that manufacture Yamaha's "Ring free" fuel additive, mostly used in Yamaha Marine division, (about $50 a quart-really good stuff). Its cheap, can't hurt anything and only help clean the system.

Re the spark plugs. Check / adjust the gap on them. They are usually in the ball park, it takes one person to drop them and throw the gap off. If stock plugs, use a wire gauge to check the clearances, adjust normally. If iridiums, again a wire gauge but adjust at the ground base strap. While your there, pay close attention to any different colors of each plug vs the others...

If you have access to a lazer temp gun, you can check temps at the top of the headers to see if onecylinder is running considerably hotter than the rest. An automotive parts store may lend it out (like borrowing tools) with a deposite..

BTW, the only time you should be smelling any "richness" is when the bike is started from cold and high idle is kicked in. You can hear and smell the richness. If you smell it when its hot, potentially an injector is leaking, or ?

 

[TownsendsFJR1300]

Also, just to add, especially from your first post.

If you put some di-lectric grease on the spark plug cap, (the rubber part that sits against the valve cover), it will go on much easier and you'll actually HEAR IT SNAP on.

I suspect that plug wire was NEVER on fully. That little bit of a bad connection will cause issues...