Very strange problem with my Gen II (Updated with pics and info)

Try going for a ride in the night or early morning when the temperatures are low and then report back. My guess is, it is lean surging at these hot temperatures. TB sync can make it a bit smooth but will not eliminate it. Sometimes a TB sync will make a lean surging condition even more glaring.
 
How many miles did you put on the 16 t sprocket? Putting the 17 on you might be feeling the uneven wear as a stutter in rpm.

Dave
 
I'll try both a non-SpeedoDRD run and a cooler temperature run.

The 16T only has about 2k miles on it so the 17T better matches the rear sprocket in wear. It was doing this with both the 16T and 17T.

@Papa... I don't think it is a lean surge because I've had all these mods done for a long time without changes and it hasn't been doing it in the past. It became apparent just in the last 3 - 4 weeks.

@Brad - LOL!!!! That was funny!!!

Thanks all! I'll get it sorted but I may not know what the actual cause is because when I lift the tank, I'll be doing a lot of things all at once. I won't have the time or patience to keep lifting the tank to try one thing at a time. :D
 
It has crossed my mind regarding the SpeedoDRD but mine is set correctly. I dialed it in to -6.8% with the stock gearing and the dash is nearly spot-on with the GPS. I managed a few sustained runs at 40, 50, 60 and 70 MPH and each time, the GPS indicated those numbers, the bike was displaying 1 MPH less than the GPS.

But, like you, it still could be a factor so I may try running the bike without it connected at all just so I can eliminate it as a possible cause.

What you describe though is just about what I am experiencing but the confusing part is the RPM needle remaining constant and unwavering. :wilynily:

Thanks for the input!! Appreciate it!

No prob, don't know if my input helped any, but as crazy as it sounds the issue mine had was definitely due to the DRD being way out of calibration. It ran perfect before I installed it, after the install ( with it calibrated way off ) the terrible bucking /surging showed up and then minutes later with the cailbration corrected, just like a light switch it was back to running fine again and all I did to make any difference was push the tiny button to recal the DRD.

Agian, seems crazy to me mine was doing what it was due to the DRD but just thought I'd make mention of it since I came across your thread.............good luck getting your issue fixed.
 
Try going for a ride in the night or early morning when the temperatures are low and then report back. My guess is, it is lean surging at these hot temperatures. TB sync can make it a bit smooth but will not eliminate it. Sometimes a TB sync will make a lean surging condition even more glaring.

Correct me if I'm wrong, but as far as I know, cooler temps and " better air " require more fuel to maintain a correct a/f ratio, so if it is lean surging at hot temps its going to be even leaner when it's cooler - nite time or early morning - so the problem would be worse when colder................unless the ecu is staying in open loop running off of fixed values, not sensor inputs which would get the ecu to try to correct the a/f.?
 
I'd put my money on a very slight lean surge, which could be caused by any number of things that would lean out the Fuel mix. As far as the speedo thing goes, it obviously corrects the reading on the instruments by interfering with the signal sent from the trans. to the ecu so who knows how that may affect the fueling. It's too bad you don't have a PCIII or V, you could add a little more fuel at the RPM and throttle openigs where you are experiencing the prioblem to se if it made it better. I'd check the throttle bodies just to see how in sync they are.
 
Are you running the stock fuel line FZ1inNH?

Yes. Replacement with rubber line is high on the list. I intend to buy enough so that when I have to lift her tank on the Purple People Eater, I will replace her line as well.

If this is a lean surge condition, why all of a sudden? These mods have all been in place for a long time without any issues. For this to start happening, something changed that I did not have a hand in. It's GOT to be the plugs/sync issue. I'll have the NGK set before this weekend so I hope to be working on this first thing Saturday morning. I hope I can report before the end of the weekend that this has been resolved. ;)

When I have the tank off/suspended, I will be doing the following:
  • AIS removal / Install blockoff plates
  • Replace OEM plugs with NGK Iridium set
  • Sync throttle bodies
  • Replace OEM fuel line with FI rated rubber and clamps
  • Flush cooling system / Replace with Engine Ice
  • Inspect Air filter / Replace if needed
  • Clean and re-seat all connectors after applying dielectric grease.

Am I missing any "under the tank" possible checks/solutions? Give it a good hard look people. :tup:

As much as I'd like to do these one at a time to see which resolves the issue (if it does!), I don't want that much down time for the bike. Riding season here is short enough as it is... A day without the bike kills me. :wilynily: At the very least, I'll have ruled out a LOT of stuff that it could have been!
 
Have the same subtle surging on my stock '08 so I don't think its your add-ons ... Doesn't bother me much though ... And you guys (and gals) know much more about these sweet machines than I do
 
The only work done over the last couple weeks was changing the tires and this past Saturday, putting the stock 17T front sprocket on then re-calibrating the SpeedoDRD but it was doing this prior to futzing with the speedo healer. Thus, no work that involved intake or exhaust or lifting the tank for any reason.

Another thing I plan on doing is replacing the stock fuel line with FI rated rubber radial hose but I don't think this is a kinked fuel line issue.

Maybe it's the Shinko Raven's? Should have bought more expensive tires? :hook2: :justkidding: Actually, the Shinko's are GREAT thus far!

I suspect the 17 tooth sprocket has the RPM in a lower range then the engine likes to run at or one that your not used to. Try downshifting when you feel the buck. One tooth on the front up or down is a pretty big change equal to like adding three teeth up or down in the back. The speedoDRD has nothing to do with what your are feeling. Your usual shift points are now different due to the 17 being installed. Try to rev out your shift points longer given the taller gearing your engine is trying to pull.
 
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Michele is ordering us a case of Engine Ice today and it will be here Friday. She also found the K&N air filter on Amazon new & shipped for $42 and change, cheaper than the D2MOTO 33% off with shipping! :tup: She managed to get all four Iridium plugs for under $23.00 (long story!), so that leaves me with a trip to the auto parts store for some FI rubber hose, clamps and dielectric grease.

@Gcontroller - I ran the bike for 10k miles with the 17T on it and never experienced this type of bucking/surging and it was fine through the transition of the 16T. Typically? I ride in the 4500+ RPM range unless I am stuck in traffic then I go to a higher gear and 2500 - 3k RPM knowing I cannot escape for a while... This is confusing because the RPMs indicated never fluctuate...

I'm hoping this isn't something with the clutch and maybe it is slipping but if it was, wouldn't it slip ALL the time, not just at certain RPMs? Or, can it slip at certain speeds and grab when you go WOT without fail? At WOT, the bike performs as expected with zero noticeable surge.

I'm betting that the plugs and sync will be the cure. New oil and filter will help out the clutch. K&N air filter will let her breathe more. Engine Ice will keep her nice and cool. And the fuel line kink issue, if it is kinked (I've not checked) will be forever eliminated.

If there's still an issue beyond all this, I'll have to start testing the spark from beginning to end and see if there's any failure there.
 
Sometimes I think I notice the same thing on my stock 07. It's really slight though. I hope to get out this Friday. I'll look for it more closely. IIRC it goes away after letting the bike really warm up with about 30-45 minutes of riding.

The bike has 7.4K miles on it. I was wondering if the upcoming second servicing would smooth out whatever it is.
 
Sometimes I think I notice the same thing on my stock 07. It's really slight though. I hope to get out this Friday. I'll look for it more closely. IIRC it goes away after letting the bike really warm up with about 30-45 minutes of riding.

The bike has 7.4K miles on it. I was wondering if the upcoming second servicing would smooth out whatever it is.

I always had a slight case of this symptom but this is much worse and very noticeable. Michele's FZ1 doesn't do this at all but she is also completely stock except for the K&N air filter.... no mods. This just all of a sudden started. Thus far, it doesn't matter if the bike is warm, cool, or hot. It's been 68 to 88 degrees over the last few weeks here and temperature doesn't appear to change it.

I hope that come Saturday night I can report that the bike is running 110% after all this work! Cross 'em if you've got 'em people! :tup:
 
I always had a slight case of this symptom but this is much worse and very noticeable. Michele's FZ1 doesn't do this at all but she is also completely stock except for the K&N air filter.... no mods. This just all of a sudden started. Thus far, it doesn't matter if the bike is warm, cool, or hot. It's been 68 to 88 degrees over the last few weeks here and temperature doesn't appear to change it.

I hope that come Saturday night I can report that the bike is running 110% after all this work! Cross 'em if you've got 'em people! :tup:

Now that you have a stock FZ1 to compare to, how does it feel compared to your modded unmapped one?
 
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