New street fighter concern.

Tay

Tay

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I just purchased a Fz1 street fighter. The bike will cut out under a load for a second and then be fine. It seems to happen around 4500 rpm. The bike has a brothers juice box ficm. The guy has tried to fix this for while and can't. I'm thinking of replacing the ecm. Does this bike have a ecm and a fuel injection module? The juice box is directly under the seat. Where would the ecm be? I'm thinking this problem has to be a electronic concern. Any info would help. Thanks
 
all full injected bikes are going to have an ecm to control the fueling. the juice box is an extra module to +/- fuel if you decide to make performance mods and need to adjust fuelling. my first guess wouldnt be a fautly ecu (that would probabaly be my last guess). the ecm is under the airbox which is under the tank. im trouble shooting a similar issue with my fz1 but mine occurs between idle and <3000 rpm. first suggestion (that others suggested to me during my trouble shooting) would be to unplug the juice box and see if the problem still occurs. does the "cut out" only happen at 4500 rpms? and does it happen every time? it could just be a fueling issue
 
I looked up the info and settings for the juice box on the website. I found the map setting was off for what the bike has. I set it to one and it seemed to make a good difference but is still there. It seems the cut out is now at a higher rpm with a heavier load. I was under the impression the juice box was replacing a factory fuel injection control module. If it's an add on to tweek fuel, I will just unplug it and plug the o2 back in. See what happens. Thanks for the help. I'll post my findings.
 
Tay said:
I looked up the info and settings for the juice box on the website. I found the map setting was off for what the bike has. I set it to one and it seemed to make a good difference but is still there. It seems the cut out is now at a higher rpm with a heavier load. I was under the impression the juice box was replacing a factory fuel injection control module. If it's an add on to tweek fuel, I will just unplug it and plug the o2 back in. See what happens. Thanks for the help. I'll post my findings.
Click to expand...

what mods are on the bike? seems like from what i have read the stock fueling is okay for one mod. so if you have more than a slip on or air box mod going back to stock may cause you to be too lean. the juice box is a good thing just need to find a good map. having the "cut out" move when you changed the map makes me think its nothing more than a fueling issue and you have to either find the right map by trial and error or spend some money and take it to the dyno to get the ideal
 
Still cuts out.

Ok. I have disconnected the jb. Hooked the o2 sensor back up. The exhaust has been removed and the stock muffler has been put back on (what looks like the stock muffler anyway). Everything as far as I know is stock. It still cuts out. I was thinking of taking the bike to Vegas to put it on a dyno. I'm just thinking it shouldn't be a real hard fix. The bike runs great besides this problem. If you ease the throttle it will run fine and not cut out at all. It only seems to be on harder acceleration. I'm new to yamaha. My last bike was a speed triple. I appreciate the knowledge from your posts.
 
I removed the tank. The fuel line is good. No kinks. I did find a " fuel cut eliminator" ( for race use only). It's obviously an aftermarket part that has been wired into the system. Could this be the problem? View attachment 16156
 
I have done some reading on the fuel cut off eliminator. It is supposed to fix the factory fuel shut off when you release the throttle it 4500 rpms. I'm finding it odd that the problem I'm having is at the same rpm that this cut off eliminator is supposed to affect. I wonder if the fuel eliminator is actually faulty and causing this issue. Ideas?
 
Tay said:
I removed the tank. The fuel line is good. No kinks. I did find a " fuel cut eliminator" ( for race use only). It's obviously an aftermarket part that has been wired into the system. Could this be the problem? View attachment 16156
Click to expand...
Fuel line has an outer sheath and that is all the you can see. Line can still be kinked underneath the sheath. This is one of those <$20 mods that is easy to do and will eliminate this as a possible issue . . .

Your problem could be any number of things including issues with FCE. FCE problems are often related to poor crimping done during installation. If you remove it you are still connecting crimped on connectors to each other.

Coil issues are also another possibility. Do some searching here and particularly on the FZ10a site.
 
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