Running like crap

[ant_mb]

Finally decided to take the FZ out for a spin on Friday, after about a month of non riding. Pulled the cover and cranked it up. Noticed right away it was ideling really rough, but though it would go away. I let it warm up and set on my way. Got to the first stop sign and damn near dropped it as I tried to take off. It was missing really bad and died as I released the clutch. I thought it my be clogged injectors so I restarted it and continued on my way. Once I got to around 4000 rpm it cleared up and ran great. I purposly rode high rpm(10,000-13,000) to try and blow out any crap on it. Didn't work!

What I've done so far:
1. Drained the tank(a real PIA)
2. Checked filter
3. Checked fire to all cylinders
4. Checked TPS in Diag mode
It counts 16-101 smoothly
Not sure what it's suppose
To be?
5. Reset idle to about 1400
6. Unpluged battery for about 30
Minutes
7. Sprayed carb cleaner down the
Throttle bodies.

None of this has helped any.
My next steps:

1. Pull the plugs.
2. Run seafoam/injector cleaner.
3. Sync the TB's
4. ????

Is there anything else you guys can think of?

 

[Cali rider]

If it runs well above 4000 rpm but misfires/stalls at low rpm you probably have a vacuum leak. Check the plugs that go into each throttle body sync hose.

 

[tuningfork]

Did you check your battery voltage? Measure it with the bike "off", you should see ~12.5 volts. It could be possible that the battery has gone bad, and that when the rpms get over 4k rpms the charging system is able to provide enough surplus power to compensate for the bike to run properly.

I would just tend to suspect electrical vs. any other mechanical type issues if it was running well when you parked it last (at least on a late model FI bike).


Motorcycle Battery Maintenace Guide - Motorcycle Maintenance Guide

 

[ant_mb]

Did you check your battery voltage? Measure it with the bike "off", you should see ~12.5 volts. It could be possible that the battery has gone bad, and that when the rpms get over 4k rpms the charging system is able to provide enough surplus power to compensate for the bike to run properly.

I would just tend to suspect electrical vs. any other mechanical type issues if it was running well when you parked it last (at least on a late model FI bike).


Motorcycle Battery Maintenace Guide - Motorcycle Maintenance Guide

I'll check, but I've actually ridden the bike on a dead battery before(had to bump start it) and it ran normal.

 

[RJ2112]

Is it possible a rodent took up residence in your air box? Or built a nest in the exhaust? Did you 'cork' the pipes when you put a cover on the bike?

 

[ant_mb]

Well I finally got a chance to pull the bike out for another looks today. Cranked it over and to my surprise it was running even worse than before. It was idling at about 900 RPM and backfiring when I would give it a little throttle. It was missing really bad!! I checked the exhaust to make sure it was firing on all cylinders, and found cylinder 1-4 exhausts to be ice cold. 2-3 were both hot.

First thing that came to my mind was a coil was going bad, but started with the simplest first. I pulled and swapped plug 3-4 as this was the easiest was for me to check if it's a bad plug or something else. Fired it up and 4 was now firing.

Turned out to be 2 bad plugs. The bitch of it is they have less than 2,000 miles on them. I haven't ridden a lot this year, and have tried to start the bike at least twice a month. My guess is all the idling fouled the plugs out.

Thanks for all the input guys.

Here is a pic of the two offenders.

 

[lytehouse]

Glad you got it all sorted out Anthony! :cheer:

 

[Erci]

My guess is all the idling fouled the plugs out.

Did you let the bike fully warm up every time you started it?
I was told that if you let it idle long enough to bring the temp way up, plugs will not get fouled up *shrug*.

 

[lomax]

I had an odd one a while back. The bike would start fine but idled very rough. It ran fine at higher RPM's. It turns out that a coil was going bad.

I don't know if that is your issue but it kind of sounds like it.

Marc

 

[Kazza]

Did you let the bike fully warm up every time you started it?
I was told that if you let it idle long enough to bring the temp way up, plugs will not get fouled up *shrug*.

Good point Erci!

I'm a little anal about that - I always warm her up to about 70'C before I get going

 

[Erci]

Good point Erci!

I'm a little anal about that - I always warm her up to about 70'C before I get going

Sorry.. I should have explained better. I didn't mean to say that you should fully warm up your bike every time before you start riding. I meant to say that if you start the bike once every 2 weeks just to let it idle (no riding at all), THAT is when it seems to be important to let it fully warm up before turning it off.

Fully warming up before riding is not necessary. In fact, many believe that you're much better off waiting only 10-15 seconds (let the idle settle) before you take off. Just take it easy until the temp comes up.

 

[ant_mb]

Sorry.. I should have explained better. I didn't mean to say that you should fully warm up your bike every time before you start riding. I meant to say that if you start the bike once every 2 weeks just to let it idle (no riding at all), THAT is when it seems to be important to let it fully warm up before turning it off.

Fully warming up before riding is not necessary. In fact, many believe that you're much better off waiting only 10-15 seconds (let the idle settle) before you take off. Just take it easy until the temp comes up.

I can't say I let it warm up to operating temp EVERY time Erci. Most times yes, but I'm sure it wasn't 100% of the time. I though Iridium plugs were almost foul proof, but I guess not.

 

[ant_mb]

Good point Erci!

I'm a little anal about that - I always warm her up to about 70'C before I get going

If I'm riding I typically let it warm up for about a minute or so then take off. I don't really get on it until it's up to temp though.

 

[ant_mb]

I had an odd one a while back. The bike would start fine but idled very rough. It ran fine at higher RPM's. It turns out that a coil was going bad.

I don't know if that is your issue but it kind of sounds like it.

Marc

Good to know. How many coils does the FZ have? I'm too lazy to pull the book. I'm guessing 2.

 

[Kazza]

If I'm riding I typically let it warm up for about a minute or so then take off. I don't really get on it until it's up to temp though.

I am in sunny Perth - only takea a couple of minutes as the outside temperature us so wa


Sent from my iPhone using Tapatalk

 

[Motogiro]

Good to know. How many coils does the FZ have? I'm too lazy to pull the book. I'm guessing 2.

Two coils....

 

[Erci]

Two coils....

Made me think of this :rof: