Bazzazz Z-Bomb Question

[750]

Apologies if this has been covered, I did a search on the whole forum and within the stickied bazzaz dyno results thread and couldn't find an answer.

I understand the Z-bomb removed restrictions in 1st through 3rd, cool...sounds great. Someone online (I do tend to take it all with a pinch of salt) has suggested the bike will run incorrectly altered air/fuel mix due to thinking it's in third all the time. Is this correct? Logic tells me no, as the bike reads the air coming in and adjusts accordingly...surely the gear wouldn't matter? Let me know!

Thanks

[lshark]

the ECU has maps for each gear....3rd gear is not restricted so that map is used for first and second gear....it's an ok $65 remedy but not without compromises ....a $375 Guhl reflash eliminates those restrictions, plus eliminates the fuel cut on closed throttle in all gears....this is a govt mandate which shuts off the injectors on closed throttle above a certain rpm....the purpose is to prevent unburned gas from getting through the cylinder....the side effect is rough on/off throttle transition, such as when leaning into a turn or during low speed maneuvers....when you open the throttle while leaned over in a turn, the response is abrupt and somewhat awkward due to a fresh charge of fuel hitting a "dry" cylinder.....the reflash allows an idle mixture to enter the cylinder at closed throttle, eliminating the rough transition ....you may have to take a ride and try to feel what i'm talking about, but you will notice the improvement with the flash.....it even makes it shift a little smoother

this is a thorough explanation of the fuel cut ....from another company but they no longer make this product

What is"fuel cut" ??

(Fuel Cut is a federal emissions regulation requirement for all EFI vehicles sold in the USA since 1980...... NO VEHICLES ARE EXEMPT !! )
"Fuel cut" happens when you close the throttle anytime above a preset rpm, in other words the injectors will stop.....
Upon re-application of the throttle, there is a delay before the system will start back up and re-wet the intake tract and combustion chamber..... the rider feels this as a delay and jerky response from closed throttle.... especially while leaned over in a turn or trying to maneuver the bike at low speeds.
This can also be heard with an aftermarket exhaust as a loud pop/bang/flame when the injectors come back on
Under these conditions, throttle response is much less than precise. I have designed the FCEtm for these bikes, and as a result there is a very marked difference as to how much better these bikes respond and behave under any riding condition....
Using this product, this bike is transformed to a perfectly smooth and predictable ride under any riding condition, and the rider can pay more attention to where he/she is going rather than how carefully the unpredictable throttle is re-applied.

All models will benefit from no loud backfiring upon throttle re-application with this product

[Skids]

So this rough feel you've been on about which was solved by the Guhl re-flash is only pertinent to US bikes? There's no such restriction on UK/Euro bikes I am aware of.

That would explain why my 14 model has no fuelling issues at all.

[hvfrdave]

The fueling on the later bikes, are far better than the fueling on the 2010-11 model. Honda addressed this by modifying the header pipes, and also the fueling map. The later model also has more bottom end, not a lot more, but enough for me to notice. The later model also runs a lot smoother at low revs. I would still fit the Z-bomb though, it would certainly give you more get up and go.

[lshark]

Europe is just as bad as our EPA....don't know if this is on EU bikes or not

my 2010 had flat spots in the midrange even after the z bomb and Zfi....gone with the reflash

[Volfy]

...This can also be heard with an aftermarket exhaust as a loud pop/bang/flame when the injectors come back on

...All models will benefit from no loud backfiring upon throttle re-application with this productThis is

The exhaust popping is unspent fuel being burnt off. A lot of bikes have secondary air injection systems that adds air into the exhaust to encourage this. There is absolutely nothing wrong with the typically amount of it. In fact, with some engines, particularly Triumph triples, this exhaust burble can actually become a signature sound of the engine. I'm very partial the the "Triple Burble". Some riders make this problem worst by introducing mods that alter the fueling of the stock engine. They almost always richen the mixture in search of more power. This worsens the exhaust popping and can get bad enough to shoot flames out of the back end.

Fuel cut actually reduces the amount of trailing throttle burbling in an engine. Again, there is nothing wrong with fuel cut if it is done correctly. Some amount of it is beneficial and produces the engine braking that most riders prefer in a trailing throttle situation. Mfrs do quite a bit of testing to make sure the amount is "just right". IMO, the VFR1200's stock trailing throttle balance feels fine. Neither is the exhaust burble excessive. For a while, I was running a shortened 2Bro M5 can with no dB killer, and that sucker was loud. IF there were any annoying exhaust popping, I would have heard it.

[lshark]

there is no testing for just right for manufacturers....the EPA mandates that fuel is cut OFF

[750]

The UK bikes won't have that EPA nonsense though, will they? I'm assuming its similar to all that EVAP gear that is put on California VFR750's etc.

I just worry about sending my ECU all the way to the states from the UK, if it gets lost then I'm essentially left with an expensive door stop.

[Artfulkatana]

It was stated that there is "popping" when the throttle is rolled on again from a closed position. I have NEVER had that problem, a slight pop when I close the throttle for engine braking, which is normal. I'm truly convinced about the flash, I will do it as soon as my recall repair is finished actually. I can feel the jerky motions from the fuel cutoff, but that's about it unless I'm engine braking.

Sent from my SM-N910P using Tapatalk

[Skids]

The UK bikes won't have that EPA nonsense though, will they? I'm assuming its similar to all that EVAP gear that is put on California VFR750's etc.

I just worry about sending my ECU all the way to the states from the UK, if it gets lost then I'm essentially left with an expensive door stop.

Nope, they're different bikes in those terms. As are the 12+ models which have much better fuelling.

You can send it tracked and be very confident it will get back to you safely surely?

[RC1237V]

The UK bikes won't have that EPA nonsense though, will they? I'm assuming its similar to all that EVAP gear that is put on California VFR750's etc.

I just worry about sending my ECU all the way to the states from the UK, if it gets lost then I'm essentially left with an expensive door stop.

I looked on the parts website (Babbitts) and the 2013 ECU was $882.29, so I insured it for $1,000.00 and had no worries..............I de-catted and put a pipe and K&N filter in, and couldn't be happier as Don did a perfect job!

[Volfy]

there is no testing for just right for manufacturers....the EPA mandates that fuel is cut OFF

I have played with enough fuel maps to know otherwise. One reason I liked Triumphs is that for many of them, you can tune the fuel map (and change various parameters) via TuneECU, which is a freeware. Attached is the stock map for the Speed Triple R I last played with. If you look at the 0% throttle opening column, trim values for all RPM positions is non-zero.

Wish I could do that with the VFR1200, but no such luck.

[750]

I liked TuneECU for my Street Triple R. Was handy for uploading standard and altered maps.

Thing is, downloaded maps are never going to be perfect, they're a ballpark guess at best - every bike is different, even in stock shape.

[Chanmenie]

Yes custom maps are preferable, but they are only as good as the guy using the dyno

[Volfy]

There is no such thing as a perfect map. Even if it is your bike on the dyno, and the guy is a seasoned pro at his craft, it is still only optimized for the set of prevailing conditions during that dyno session. Conditions change all the time - both the bike and atmospheric. It's up to the rider to determine if good enough is actually good enough. It does help that a lot of bikes these days have close loop feedback control (lambda sensor, knock sensor, etc.) and dynamic adaptation.

[MotardMenace]

I have a question on the Z-Bomb for those that have it. I would obviously love to eventually get the Guhl map but thought I might try this first for a while. The bike I purchased has the Bazzazz TC/FI controller with quick shifter. This is compatible with the Z-Bomb isn't it? Thanks

[crakerjac]

Yes. Z-Bomb is compatible. The Z-Bomb connects to the Gear Position Sensor (GPS) harness just above the shifter. It has no electronics inside it, so it does not care what other mods have been done to your bike.

[MotardMenace]

Yes. Z-Bomb is compatible. The Z-Bomb connects to the Gear Position Sensor (GPS) harness just above the shifter. It has no electronics inside it, so it does not care what other mods have been done to your bike.

Thx

[750]

So, can anyone give me a yes/no answer then - will the Z-bomb at all fuck with a/f ratio - as far as I'm concerned it's just telling the bike it's in another gear, so should be of no consequence. Right?

[hvfrdave]

So, can anyone give me a yes/no answer then - will the Z-bomb at all fuck with a/f ratio - as far as I'm concerned it's just telling the bike it's in another gear, so should be of no consequence. Right?

The Z-bomb, was one of the first mods I did on the VFR1200F, way before I de-cated the bike. The Z-bomb did not and does not interfere with the fueling. The Z-bomb transforms the acceleration in 1st and 2nd gear, as I have said many a time, by far the best value for money modification you will ever spend on your VFR1200.

[750]

So, can anyone give me a yes/no answer then - will the Z-bomb at all fuck with a/f ratio - as far as I'm concerned it's just telling the bike it's in another gear, so should be of no consequence. Right?

The Z-bomb, was one of the first mods I did on the VFR1200F, way before I de-cated the bike. The Z-bomb did not and does not interfere with the fueling. The Z-bomb transforms the acceleration in 1st and 2nd gear, as I have said many a time, by far the best value for money modification you will ever spend on your VFR1200.

There we go, nice simple answer.

I just bought one for a smidge over £30 :)

[Chanmenie]

Yes Dave knows his stuff

How did you manage that John second hand ?

[750]

Yes Dave knows his stuff

How did you manage that John second hand ?

Yep, donated the money to a charity of the chaps choice and he's got it out in the post for me today. Coming from the states to the UK. Happy days, everyone's a winner :)

[Chanmenie]

Nice one

[CandyRedRC46]

the ECU has maps for each gear....3rd gear is not restricted so that map is used for first and second gear....it's an ok $65 remedy but not without compromises ....a $375 Guhl reflash eliminates those restrictions, plus eliminates the fuel cut on closed throttle in all gears....this is a govt mandate which shuts off the injectors on closed throttle above a certain rpm....the purpose is to prevent unburned gas from getting through the cylinder....the side effect is rough on/off throttle transition, such as when leaning into a turn or during low speed maneuvers....when you open the throttle while leaned over in a turn, the response is abrupt and somewhat awkward due to a fresh charge of fuel hitting a "dry" cylinder.....the reflash allows an idle mixture to enter the cylinder at closed throttle, eliminating the rough transition ....you may have to take a ride and try to feel what i'm talking about, but you will notice the improvement with the flash.....it even makes it shift a little smoother

this is a thorough explanation of the fuel cut ....from another company but they no longer make this product

What is"fuel cut" ??

(Fuel Cut is a federal emissions regulation requirement for all EFI vehicles sold in the USA since 1980...... NO VEHICLES ARE EXEMPT !! )

"Fuel cut" happens when you close the throttle anytime above a preset rpm, in other words the injectors will stop.....

Upon re-application of the throttle, there is a delay before the system will start back up and re-wet the intake tract and combustion chamber..... the rider feels this as a delay and jerky response from closed throttle.... especially while leaned over in a turn or trying to maneuver the bike at low speeds.

This can also be heard with an aftermarket exhaust as a loud pop/bang/flame when the injectors come back on

Under these conditions, throttle response is much less than precise. I have designed the FCEtm for these bikes, and as a result there is a very marked difference as to how much better these bikes respond and behave under any riding condition....

Using this product, this bike is transformed to a perfectly smooth and predictable ride under any riding condition, and the rider can pay more attention to where he/she is going rather than how carefully the unpredictable throttle is re-applied.

All models will benefit from no loud backfiring upon throttle re-application with this product

For what its worth, I have tuned my 2007 vfr800 vtec using Rapid Bike Racing and 4 wide band o2 sensors, closed loop tuning, data logging and an AFR readout. I have found that there is a fuel cut on the vfr vtec, but it is only in gears 4th, 5th and 6th. There was no fuel cut in the lower three gears.