07 Busa Idle stumble & intermittent misfire HELP.

[evo]

Hello,
For reference this bike is very new to me. Only had a couple weeks, I'll list engine related mods and symptoms.

2007 6700 miles (did not have a speedo healer w/ 16/42 gearing so it's actually less)
Muzzy full system 4-2-1
It may have Pair Valves blocked - it does not pop under decell.
BMC Filter w/ small Airbox mod
PC3 USB (mapping unknown @ the present time - haven't downloaded to view)
Cycle Tech Air shifter & shift light (currently not functioning/bottle empty. Lol)

I recently flushed coolant & changed oil as well as some minor repairs/cosmetic updates, unrelated to symptoms.

Symptoms:
at idle, approx 1100-950 would fluctuate mildly and occasionally hick-up. I bumped idle speed to 1200, is a lil better. As engine warms up it's more stable but the stumble is there.
Shift into 1st gear and engage clutch, start to accelerate the bike will drop a cylinder and sputter than pick up and go above 3500-4k rpm, does this in 2nd and 3rd occasionally. At cruising speed of 65+ I can feel an engine vibration around 4k. As I pull up to stop lights in Neutral, it will have an intermittent cylinder drop and pick up. It definitely a dead cylinder dropping.

Bike seems to pull well up to speed, nothing radical tho, So far I'm not very impressed. I also have a 94 GSXR1100 that's worked pretty good, so other than my 06 R1 & my recently sold 08 ZX10R, not much to compare it to.

My History, I own many bikes, this is my first Busa. I am a auto mechanic. I have a keen ear for symptoms like this. So, my question for you seasoned Hayabusa owners is, where do I look first?

The obvious diagnostic steps would be to #1: Pull Spark plugs #2 Compression test #3 inspect OHM Coils #4 check fuel injectors... I'm not aware of any common issue that may help alleviate some troubleshooting time. The FI has never come on, should I try and pull codes? Could the previous owner have pulled the FI bulb, so it doesn't illuminate (I've seen this with cars)?
With the current mileage and over all condition, I didn't expect any mechanical issues, so curious of any problematic or notorious component failures...

Thanks in advance & I look forward to a long stay here.
I've been a member on GDC for about 10 years.

- Cheers

 

[02BusaMark]

Disconnect the positive lead from your PC and see if this clears up your hiccup.

 

[evo]

Ok, I'll try that this afternoon. I'm going to pick up some Plugs also. Just didn't think at roughly 5-6k they would need a change, but who knows what punishment the bike went thru previously.
Very strange other symptom is my Accumen gear indicator (I installed) I hooked up and calibrated was working fine. I recently installed the SpeedoDRD and calibrated for the gearing & now both my Accumen is off, very sluggish and will not register 5-6 gear, also my shift light intermittently comes on at any rpm, even idle. But the shift light works as normal where the rpm is set. I did notice when removing Airbox previously, there is a wire connected to each ignition coil, assuming an ignition interrupt for the air shifter unit? I'm going to rec-calibrate the Accumen today on the rear stand, assuming the Speedo healer screwed it up & test against GPS.

 

[1bondoman]

Put plugs in before u do anything. Bike plugs are very temperamental

 

[evo]

Yea, I figured as much. I work on PWC also, a common symptom on the 4stroke Yamaha Waverunners is not revving past 4k rpm and 15mph limit. Toss fresh plugs and run like new. Strange thing is, the electrodes will be clean and no signs of rich/lean condition, it's as if they internally short. Thanks for the tips. I've had battery disconnected for about an hour now. Also, assuming I can relearn my Accumen gear indicator, it did state in the Speedo DRD instructions to add it after any piggy backs, however it's a plug and play unit @ trans speed sensor and the Accumen is tied into the wiring at the Meter cluster, not sure that's reasonable, I'll try and see what what happens.

 

[evo]

Ok, so I had some CR9EK plugs here in the shop already. Same I use in the Kawasaki STX12 &15-F Jetskis. Anyway, I remove Spark plug Cyl#1, plug loose. Pull it out, its a CR9E, gapped @ .08mm as were all others. I removed and installed new correct dual electrode versions. First impression, stable idle, much crisper throttle response. Ill take for a spin later on. Re-set ECU & reprogrammed the Acumen gear indicator. Will reply after I take a ride with any improvement or not. I have also confirmed the FI light does come on then go off with engine start.
Thanks for the help up front.

 

[Boosted Cycle Perf]

I'd suspect plugs too, but if that doesn't help disconnect the power commander.

 

[evo]

I was beginning to wonder if there was a tre installed, but looked around and could not locate. May be behind the Left side fairing, but only briefly pulled back to install the SpeedoDRD a few days ago & didn't see anything.
I will update shortly after a ride, but lemme finish this beer first. Lol

 

[1bondoman]

Ok, so I had some CR9EK plugs here in the shop already. Same I use in the Kawasaki STX12 &15-F Jetskis. Anyway, I remove Spark plug Cyl#1, plug loose. Pull it out, its a CR9E, gapped @ .08mm as were all others. I removed and installed new correct dual electrode versions. First impression, stable idle, much crisper throttle response. Ill take for a spin later on. Re-set ECU & reprogrammed the Acumen gear indicator. Will reply after I take a ride with any improvement or not. I have also confirmed the FI light does come on then go off with engine start.
Thanks for the help up front.

Cr9e is fine you just can't start it and shut it right back off. I have found as long as you let the bike warm up before you shut it off they do fine. The cr9ek does hold up better with a lot up start ups and cold shut downs.

 

[dadofthree]

Plugs, fuel tank look clean inside ? Bike has sat a lot. These bikes pulllike crazy and at 4k that front tire gets light.

 

[evo]

Update, took for a spin yesterday. Ran as it should, the intermittent cylinder drop must have been the loose spark plug. Yes, I understand the theory behind the CR9E, but being a copper plug, it doesn't have the same lifespan, nor does it have the twin electrode. Perhaps the ignition is sensitive to it, I dunno. But I took up a back road then to highway, maybe a 5 mile circuit and ran thru the paces, hit maybe 130mph. The stumble is gone as well as the hesitation off idle and at lower rpms. I believe that annoying vibration is gone as well, didn't ride long enough to really pay attention, was too busy navigating traffic. It does pull much stronger now, but not nearly as brutal above 9k like my GSXR 1100 w/ Flat-Slides.

Acumen is registering all gears now & the shift light is not being a nuisance anymore.

Yes what I can see of the fuel tank it's spotless. I have read up on the Fuel pump mods and adding an inline filter, something I may do down the road. Speaking of pumps, my track bike pump died, sitting.... It's an 03 GSXR600. There is a retrofit Chrysler minivan pump that fits, not sure if same would work in the Busa or not, if I ever needed to? But I've tackled this dilemma a few times.

I look forward to a few additions like Stacks, FP trans star and ignition advancer. I'm going to look into a reflash also, so I can remove the PC3.

After much research I believe I'm going to try the new Perelli Angel GT series tires as well.

Thanks for all the helpful insight.

 

[1bondoman]

Cr9e's were good enough to go 5.10 8th mile and 7.80 1/4 mile.

 

[dadofthree]

Glad you got it now, Grip It and Rip It