Engine Cuts Out at 3500RPM

[NonSmallJohn]

Hi, this problem is pretty hard to explain, but I'll try my best.

I bought my 2011 fz8 with only 2400km this past April. The problem I'm noticing is at exactly 3500RPM there is a distinct "click", it sounds like an electronic click, such as a relay. Power is then lost for a very brief moment. It only happens when going up through 3500, not down. For example, if I'm driving in 1st gear at 37km/h at exactly 3500 RPM the engine cuts in and out over and over because the RPM is hovering around the 3500 mark. It is very jerky and very dangerous at times. The sound seems to be coming from the right side just under the gas tank, then again, it's hard to tell when your driving around. Anyone know what's going on?

Thanks

Mike

 

[Blackfin]

Hi, this problem is pretty hard to explain, but I'll try my best.

I bought my 2011 fz8 with only 2400km this past April. The problem I'm noticing is at exactly 3500RPM there is a distinct "click", it sounds like an electronic click, such as a relay. Power is then lost for a very brief moment. It only happens when going up through 3500, not down. For example, if I'm driving in 1st gear at 37km/h at exactly 3500 RPM the engine cuts in and out over and over because the RPM is hovering around the 3500 mark. It is very jerky and very dangerous at times. The sound seems to be coming from the right side just under the gas tank, then again, it's hard to tell when your driving around. Anyone know what's going on?

Thanks

Mike

When you turn the key from off to on what sounds do you hear from under the tank? Has that changed?

I'm wondering if the subthrottles are doing something weird on you.

Might be interesting to lift the tank and pull the top cover off the airbox. I'd also pull the intake funnels off to give you a clear view of the subthrottle plates. Then start the bike and, with the rear wheel securely off the ground, put it in first and rev it to ~3500 and observe the plates to see if anything strange happens (e.g. they snap shut momentarily?)

If you do this use all necessary caution to ensure the safety of yourself and others. Keep kids & pets away, for example...

 

[NonSmallJohn]

Thanks for the quick reply! When I turn the key on it's a interesting noise, hard to describe, sort of jittery/ticky (Maybe I'll make a short video clip when I get a minute). Also the fuel pump can be heard. I will try out the idea you've suggested this weekend and see what happens. If the throttle plates do snap shut, what would you suggest as the next step?

Thanks

Mike

 

[TorontoAlex]

On startup the bike initialises and does a funky 0-11000 on the tach and thats all normal.

Wild ass guess but maybe rectifier regulator?

 

[Weekend Casualty]

i will say that when i turn the key to start my bike it also does a sort of "system check" that sounds like a robot trying to wake up. I'm thinking thats the noise you're describing but i could be wrong. Mines made that for two years and never given me a problem. The engine cutout however is something i cannot explain.

 

[NonSmallJohn]

My bike is in storage very far away from my current location, so it took me a while to make this video. This is the noise my bike makes on start-up, not sure if it's normal.https://www.youtube.com/watch?v=_g2sueVfy5g

 

[Blackfin]

My bike is in storage very far away from my current location, so it took me a while to make this video. This is the noise my bike makes on start-up, not sure if it's normal.https://www.youtube.com/watch?v=_g2sueVfy5g

Sounds normal to me. If you lift the tank and remove the air box lid and peer down into the air funnels when you key on you'll see the sub-throttle plates cycle during this time. The PCM is checking their function. At least some of those nifty sounds is coming from the sub-throttle stepper motor.

 

[NonSmallJohn]

When you turn the key from off to on what sounds do you hear from under the tank? Has that changed?

I'm wondering if the subthrottles are doing something weird on you.

Might be interesting to lift the tank and pull the top cover off the airbox. I'd also pull the intake funnels off to give you a clear view of the subthrottle plates. Then start the bike and, with the rear wheel securely off the ground, put it in first and rev it to ~3500 and observe the plates to see if anything strange happens (e.g. they snap shut momentarily?)

If you do this use all necessary caution to ensure the safety of yourself and others. Keep kids & pets away, for example...

I'll try what you suggested next season (April-May 2016). I know it's a long ways away, but I'll let you know the outcome.

Thanks

Michael

 

[Mikz86ta]

Mine makes same noise on startup. Seems like your noise is 'quicker clicks' but largely the same.
Aside from that, does it cut out at 3500 in all gears and riding situation? Same with light throttle input and hard throttle input?

 

[NonSmallJohn]

It does happen in all gears, but it's definitely more noticeable in in the lower gears. It's a very quick cutout so It's not noticeable with hard throttle inputs. However it does happen all the time and can be very dangerous at times due to the jerky nature of it. I'm eager to find out what's wrong with it, but I'll have to wait till April before I can do anything major to it.