Slow decline to an ultimate death

Hello to the FZ1 world! I'm new to the forum as far as posting, but have used so many of these discussions to help troubleshoot. A couple of months ago I purchased a 2009 Yamaha FZ1. This being my first bike of this caliber, I wasn't sure what to expect, how the bike was going to feel, how much glorious power it was going to have, etc.

I have had a strange start with my new bike. Here is my history of moments of joy and frustration… fairly detailed, but I think it’s a weird enough situation that it’s important.

My first ride was a test ride.. I enjoyed it very much, decided to buy it. My second ride was from the craigslist location to my house. The second ride seemed a little different, and the bike seemed difficult to ride at low speeds. I just assumed new bike, new style of bike from what I’m used to.. give it some time. I had a friend who is more familiar with this type of bike test ride it and he felt as though something was weird cause it was snatchy, and a had a flat spot in the fueling. I disconnected the Juicebox that the previous owner had installed… Felt like a NEW bike all together. I felt comfortable, began riding it to work and just for fun… Talked to many people, decided the Juicebox had probably “gone bad”.

Then… riding on the highway, I noticed there was a bit of jumpiness in low rpms (3-5k) in 5th and 6th gear. Perhaps the bike didn’t like riding in this area I thought? I noticed the speedo numbers began jumping around from one random number to another.. 55, 82, 23, 66 (not the actual numbers), and then it went away. There was also some hesitation in the acceleration/throttle. I thought maybe a sensor? No error codes/check engine light by the way. Ignored it and planned to keep an eye on it. When I was out for a joyride, after an earlier hour and a half ride, it began happening again, but this time the throttle was very snatchy, and the speedo problem was happening in any gear, not just highway speeds. It felt unsafe to ride, so I nursed my way back home and decided I needed to look into what was going on.



My brother-in-law knows a great deal about motorcycles, and works on commercial airplane engines. He talked with me extensively and came over to test all wiring/electronics to make sure there were no shorts and voltages were good. Checked fuses, good. I’m pretty confident that we are in check there.

Next changed spark plugs and all 4 ignition coils. The problem still occurred (weird speedo number flashing and snatchiness), and seemed to come on much more quickly. Next day, error codes 13 (air intake sensor), 23 (atmospheric pressure sensor), and 41 (lean angle sensor [open or short]) showed up and the bike wouldn’t start. Next day, error code 12 showed up. The previous owner had the same issues and symptoms in 2012, and was at the point where the bike wouldn’t start. He brought it to a dealer, they condemned the ECU, replaced it and fixed the bike. SO, I purchased the most updated ECU (2011+) and plugged it in, and sure enough it seemed as though everything was gold. Bike was running smooth, felt great. DAY 1: Took two rides about 30 minutes long around town, nothing crazy. DAY 2: Took a long morning ride and about an hour into the ride THE SPEEDO STARTED DOING THE SAME THING, the bike became difficult to ride, and died. I pulled over, let it cool started up and rode with flashers (thankfully I was on my way back home, only a few miles away). Bike seemed okay for a couple of minutes, then died. Let the bike cool, started up and made it home with my head hanging quite low..

I am at a loss right now as to what my next move is. Previous owner installed a Delkevic slip on, and removed the SERVO motor. Perhaps this is an issue? Perhaps the crankshaft position sensor is bad? Speedo sensor? Bike wiring harness? I am hoping I don’t need to go on a wild goose chase with this one, and perhaps someone has experienced something similar or has some ideas. I’m very open to ideas and criticism, as I am here to learn!

Thank you for reading!
Chris
 
Wow!!!....mine had a snatchy throttle at 4K RPM’s and it was solved by Ivans ECU flash. This seems like somethng worse. If you get it sorted to where its just doing what mine did try the flash. Good luck.
 
Wow!!!....mine had a snatchy throttle at 4K RPM’s and it was solved by Ivans ECU flash. This seems like somethng worse. If you get it sorted to where its just doing what mine did try the flash. Good luck.

Yeah, I've read many stories of a snatchy throttle, but this is something different. Prior to the bike "malfunctioning" the throttle response/acceleration is actually smooth as butter. Then something happens, potentially when the bike is hot for a certain period of time. Thanks for the advice, we'll see where this goes.
 
It sounds like you have a short somewhere that is only activated while you are riding.

I'd start by checking all the wires and plugs to see if you have a bad one somewhere that was missed with the standing inspection. I'd start by checking the ones around the headstem for wear.

Also check the plugs in the harness where the juice box was plugged in.
 
It sounds like you have a short somewhere that is only activated while you are riding.

I'd start by checking all the wires and plugs to see if you have a bad one somewhere that was missed with the standing inspection. I'd start by checking the ones around the headstem for wear.

Also check the plugs in the harness where the juice box was plugged in.

Yeah, I think you are right. I just found a nick in one of the wires to the plug that goes into the servo motor. The previous owner had taped it, and had some servo motor eliminator plugged in, I assume to trick the ecu. Lots of heat is generated in that area, so this could certainly be an issue. I'm going to get some assistance in repairing that wire, and get the servo motor and stock exhaust installed (hopefully very soon!!). I'm going to wait for some help with the wire, since it would be my first repair in that department. In the meantime, I'm going to continue to inspect wiring and look for any wear and tear, or places that look like someone tampered with and covered up.

The only weird outlier is the speedo. I am remembering now when I got the new ECU and if was feeling awesome, the speedo lagged a bit when pulling to a stop. It would start lagging around 15mph and then would crawl to 5mph, then just hit 0mph. And the speedo ALWAYS starts acting crazy just before it starts to sputter and get snatchy...and momentarily die..
 
It sounds like you have a short somewhere that is only activated while you are riding.

I'd start by checking all the wires and plugs to see if you have a bad one somewhere that was missed with the standing inspection. I'd start by checking the ones around the headstem for wear.

Also check the plugs in the harness where the juice box was plugged in.


I repaired the frayed wire just behind the plug where the servo motor goes. Installed the servo motor and stock exhaust. First ride, seemed to be okay (aside from lord knows what was inside that exhaust from the previous owner). Second ride, different day, pulled out of the driveway and got aggressive on the throttle. Speedo lost it's mind and started flashing random numbers all over the place. This is usually the first thing that occurs when the bad symptoms arise. I didn't have time to ride and get stranded so I just came back. I'm waiting on a speedo sensor that I ordered.

Could a faulty speedo be confusing the ECU into running poorly?
 
With all that and no code, that is unfortunate. If it was my truck the Speedo issue would be the crankshaft position sensor. Not sure where the Speedo is connected to. You could always remove the sensor, inspect, clean and reinstall to see.
 
With all that and no code, that is unfortunate. If it was my truck the Speedo issue would be the crankshaft position sensor. Not sure where the Speedo is connected to. You could always remove the sensor, inspect, clean and reinstall to see.

I actually just purchased a new speed sensor, since it's not super expensive. Replaced the speed sensor with the new one yesterday... same exact symptoms. It rides fine for a little bit, but the speedometer numbers jump around quite manically when I give it a decent amount of throttle, and numbers are not smooth on deceleration. Once the speedo starts doing that, the bike gets very jumpy and the throttle becomes anything BUT smooth. Then it idles like garbage and either dies or really wants to die.

I've spoken with someone from a repair shop, he suggested to bring the fuel injectors in for a cleaning as the next step. He also said to get the bike started and give the wiring harness a shake to see if the speedo does anything funky. Those are my next two steps at this point. I am so thankful I currently have an older bike to ride during all of this!!
 
It sounds to me like you have a wire chaffing somewhere still , and giving you those trouble codes , a ball ache I know but you need to remove more bits and carefully follow the loom , also check the connectors on the left side of inner fairing ( if its the s model ) injectors wont cause the speedo issue .. any other random symptoms....another avenue to explore is the earth connections in the loom , can be found on right side of the frame in the corner where the loom goes around the back of the engine, you will need to cut the loom open to access the two white earth connecting blocks , you can take these apart , you will be surprised how much shit these can cause you!
 
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Thank you to all who have read my post and thought through some possible troubleshooting ideas. I eventually got REALLY tired of throwing parts and sensors and frustration at the bike and waved the white flag.. Here is the update:

I ended up taking the bike to two places. First place was recommended by a friend, not a dealer, but a repair shop that is known to figure out weird issues. I brought it there and the bike would NOT malfunction. Left it there while I got married and went on a honeymoon.. all the guy said was "this bike is sick, no problems, blast to ride!" ... So I rode it home about an hour, with my buddy riding behind me. He said all he could smell was unburned gasoline the whole time, and NO it was not riding smooth and the speedo was acting like a lunatic. All of my test rides after that ride home lasted about 15 minutes before running like garbage, and then idling like crap, and eventually dying. Cold start, perfect, first 10-15 minutes of riding perfect, after that... awful.

I then took it to a Yamaha dealer (10 minute ride away) and it died as I pulled into their parking lot. Actually hilarious... Anyways, **LOOKS LIKE WE FOUND A SOLUTION**

Here is the resolution on the paperwork:
INSPECTED BIKE
SCAN FOR CODES NONE
TEST RODE
COLD START OK
AT 170 DEGREES IDLE STARTED TO SURGE AND STALL
PARTIAL THROTTLE OPEN MOTOR SKIP, SURGE WIDE
OPEN OK
BIKE HAS AFTER MARKET COILS
CHECKED COILS OKAY
REPLACED SPARK PLUGS, WERE BURNING RICH. TEST
RIDE. STILL STALLING
HAVE TO REMOVE RADIATOR TO REPLACED SPARK PLUGS
CHECKED WIRING, CONNECTORS, WIGGLE TEST
INSPECTED AIRBOX
INSPECTED AIR INDUCTION SYSTEM
AND FOUND A RESITRICTION IN THE INTAKE HOSE. CLEARED HOSE.
ASSEMBLE BIKE. TEST RODE. BIKE FIX.

The previous owner made all sorts of modifications, and plugging up the AIS hose was one of them. I saw that in a youtube video somewhere as part of some stupid airbox mod. My friend and I did notice a weird tinfoil cover to one of the hoses, thought it was some cheap fix to cover something. Anyways, the bike has been riding MINT. I am assuming that al the surging in the engine was communicating something through the ECU to screw up the speedo. I'm still crossing my fingers and being cautious, but good lord it feels good to be back on the bike!!
 
Glad you got it sorted.

It sounds like the previous owner blocked the AIS without doing the PCV install and O2 sensor removal or ECU flash.
 
Glad you got it sorted.

It sounds like the previous owner blocked the AIS without doing the PCV install and O2 sensor removal or ECU flash.

Yeah exactly. I probably won't be doing any modifications at this point. The bike is riding so nicely and is PLENTY fast for me. I do have 2 Delkavic slip on exhausts and will probably make that change at some point. Mostly cause the stock 20lbs mailbox on the side of the bike isn't my favorite thing...
 
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