Bike is in the shop

[jtarkany]

Well, just finished the fork swap and got to ride it for one day. Took it out again yesterday and when I rolled on the throttle she just bogged down. If she had a carbeurator I would of thought she was flooding.

Lifted the tank, checked all of the vaccum lines, checked the fuel filter, plugs and wires were just replaced 2,000 miles ago.

Zipped her back up and tried it again, same problem, if I ease on the throttle all 4 cylinders run strong, if I roll on the throttle it feels like it has dropped a cylinder or two, I mean it's bad.

I was at my wits end so I took it into the shop. They checked everything I did and seem to be confused, their theory at present is that the coil may be going bad or grounding out somewhere.

Anyone else experienced anything like this or know what the cause may be, any hints on what direction I might suggest the shop go in, they are going to call Yamaha on Tuesday to see if they have any input.

Thanks in advance for any help. They better get it running before Aug. 5th so I can hook up with the FZ6 Forum Mega Ride

 

[lonesoldier84]

They better get it running before Aug. 5th so I can hook up with the FZ6 Forum Mega Ride

Damn straight.

 

[Cali rider]

Can you duplicate the lack of power when the bike is at a standstill by just grabbing a handful of throttle? If so, hook up vacuum gauges and see if just one cylinder is dropping or if it's pair 1-4 or 2-3. Ignition is common to each of those pairs as well as injector firing. If you can keep it running rough, let it go for 30 seconds then kill it and take a plug reading.

Wet plugs= ignition.
Dry= lack of fuel.

If it will only happen under load you can isolate the suspect cylinder by taking an exhaust header temp measurement after riding it hard for a short time, killing ignition and quickly stopping to check.

If I had to guess, I would say ignition coil connection/failure is most likely, with low fuel pump pressure as second choice.

 

[jtarkany]

Thank you, I will discuss this with them on Tuesday as they are closed today and Monday :thumbup:

 

[VEGASRIDER]

Obviously the fuel is out of the question? Could have it been contaminated?

 

[Kamloops]

TPS perhaps? Was it not recalled. Did you get it replaced.

What are the Symptoms of a Faulty TPS?

* Stalling
* Irregual idle
* RPM Drop while acclerating or trying to maintain a constand speed.
* Drop in fuel Mileage
* Poor Throttle Response

Found this but it may not work for fz6 as it was for fz6r

To check the TPS values, you have to press and hold SELECT + RESET, then turn the key and keep them pressed for 8 more seconds.

It'll appear dIAg on the display, you can release them now. Afterwards use select until you see a d01 (Diagnostic Mode for the TPS)

Then it should read between 15 and 17 if the throttle is closed,
With the throttle fully open, it should read between 97 and 100.

If the values are over or below those I mentioned, the TPS should be replaced.

To leave the dIAG mode, simply turn the key counter clockwise.



Also maybe something here may help?
http://www.600riders.com/forum/garage-mechanical-help/29706-bogging-down-loss-power.html

 

[jtarkany]

Obviously the fuel is out of the question? Could have it been contaminated?

Good thought but I don't think it's the fuel, I fuel up at the same place and the tank I've been running on was doing just fine for about 150 miles and I only use one can of NOS per tank :BLAA:

TPS perhaps? Was it not recalled. Did you get it replaced.

What are the Symptoms of a Faulty TPS?

* Stalling
* Irregual idle
* RPM Drop while acclerating or trying to maintain a constand speed.
* Drop in fuel Mileage
* Poor Throttle Response

Found this but it may not work for fz6 as it was for fz6r

To check the TPS values, you have to press and hold SELECT + RESET, then turn the key and keep them pressed for 8 more seconds.

It'll appear dIAg on the display, you can release them now. Afterwards use select until you see a d01 (Diagnostic Mode for the TPS)

Then it should read between 15 and 17 if the throttle is closed,
With the throttle fully open, it should read between 97 and 100.

If the values are over or below those I mentioned, the TPS should be replaced.

To leave the dIAG mode, simply turn the key counter clockwise.

Also maybe something here may help?
http://www.600riders.com/forum/garage-mechanical-help/29706-bogging-down-loss-power.html

Thanks for this information, doesn't exactly fit the symptoms but maybe, what is a TPS?

 

[Kamloops]

Good thought but I don't think it's the fuel, I fuel up at the same place and the tank I've been running on was doing just fine for about 150 miles and I only use one can of NOS per tank :BLAA:



Thanks for this information, doesn't exactly fit the symptoms but maybe, what is a TPS?

"rolled on the throttle she just bogged down" That is one of the main symptoms of a faulty TPS from what I understand.

TPS - Throttle Position Sensor

 

[Cali rider]

Any update on this subject?

 

[jtarkany]

Checked in today, they said they have narrowed it down to a fuel supply problem, I mentioned the TPS, they said they had already checked it and it wasn't the problem.

I'll be checking back with them tomorrow.

Thanks for all of the suggestions, keep your fingers crossed :thumbup:

 

[jtarkany]

Bike is back and running great, only took 8 hours for the shop to figure out it was a bad plug :shakehead: I only paid them for 3 hours, that should have been one of the first things they checked.

 

[VEGASRIDER]

How many miles on the plug? Did they end up changing all four? You have any pics of the bad plug?

 

[FB400]

Lest I digress... Wasn't the TPS problem resolved prior to 2006?

 

[kevlarfz6]

Lest I digress... Wasn't the TPS problem resolved prior to 2006?

Yep. The TPS problem is only on the '04s and '05s, it was fixed with the '06s.

 

[jtarkany]

How many miles on the plug? Did they end up changing all four? You have any pics of the bad plug?

The plugs were just switched out 2,000 miles ago, the plug was apparently defective, no pictures.

Lest I digress... Wasn't the TPS problem resolved prior to 2006?

As suggested I asked the shop about the TPS, they said that it was solved prior to 2006 but they checked it just in case, they mentioned that the TPS would cause poor perfromance but would not cause the bike to drop a cylinder.