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Discussion Starter #1 (Edited)
Here we go again, must be winter again, seem to look at this every year !
This time I've been doing some bench tests.

As most know, with the 1000S models the engine will rev freely in neutral but when put in gear, it feels sluggish, strangled.

I have put together a Ducati ecu that was kindly donated to me together with an rpm simulator and a few simulated sensors and switches. I'm running a tuned F41000S eprom and logging it all on the MIAW software.

Sensor inputs for this test are ecu standard so no other trims will effect the output.

Revving the engine from 1000 - 5000 rpm using an even gain of throttle to a maximum of just 10 degrees as you would on the road, the advance is evenly retarded up to 20 degrees at 5000rpm.

1000 - 5000 @ 5000rpm in gear 28 degrees, in nuetral 48 degrees (-20)
2000 - 5000 @ 5000rpm in gear 35 degrees, in nuetral 48 degrees (-13)
3000 - 5000 @ 5000rpm in gear 45 degrees, in nuetral 48 degrees (-3)
4000 - 5000 @ 5000rpm in gear 48 degrees / in nuetral 48 degrees (0)

I can't figure out what is meant to be happening.
You would expect the advance at 5000rpm to be the same where ever the start point was, TPS is always around 10 degrees at 5k ?

Any ideas?

<
Edit:I guess at 1000 rpm it just has a bigger retard amount to start with than at 4000 rpm ?
>

Anyhow, once found it will be straight forward to eliminate but then it will all need tuning again !

Cheers
Adam
 

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Kudos to you for your efforts Adam. It's very odd to me as well, as we've discussed. Noel, any input here? Anyone else?

John
 

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Discussion Starter #3
We will have some software finished soon that will allow simulation of any given engine/throttle speeds that can be repeated time after time in batch fashion.

Together with complete control of all the sensors, this will be perfect for graphing and logging the differences in the advance output between in gear and in neutral :)

Will post more when its's done.....soon it will be fixed JAndrewG !
 

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I really look forward to your results.

Had mine dynoed and the dyno guy told me he never saw such strange ignition settings like on my MV. He adjusted it to standard settings he was familiar to from other 4-cylinders.

Bike runs very smooth, burns much less fuel.

Jochen
 

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I wrote this some years ago for James Corrells FAQ website:

Monday, November 28, 2005
Tuning 4) F4 1000; Idle, throttle, blipping issues

submitted by MikeT

If anyone is wondering about why their MV1000 revs differently/sluggish when put in gear, I suspect that MV have done this by retarding the ignition timing, and progressivly advancing it again, so all's back to std by about 3000 rpm. The "sluggish" part is activated by the neutral switch to make the bike tractable in the very low rpm's, don't forget all the jap multi cylinder 1000's have a twin throttle system were you open one set and the engine vacuum/ECU opens the second set, MV don't have the room to do that due to the compact nature of the airbox etc. You could try"cutting" the neutral light input to the ECU which may get rid of the sluggish under 3000rpm bit, I must admit if you take off with some "gusto" and it goes over 3000rpm whilst also slipping the clutch it does rear it's head up!.
 

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Discussion Starter #6
Hi Mike, yes I read all that years ago as well, good write up. ;)

It's you that made me try and figure it all out and do something about it.

I shifted the ebs cut off point a tad lower to help prevent the 'no blipping effect' during normal riding.

As you said in your article, correct fueling and ignition timing also helps.

Now for the retard in neutral part....

Cheers
Adam

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I think you may end up a very sensitive low rpm throttle if you restored the advance? good project though!!
 

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Hi Mike, yes I read all that years ago as well, good write up. ;)

It's you that made me try and figure it all out and do something about it.

I shifted the ebs cut off point a tad lower to help prevent the 'no blipping effect' during normal riding.

As you said in your article, correct fueling and ignition timing also helps.

Now for the retard in neutral part....

Cheers
Adam

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Hi Adam, I assume that the 750 models do not have this feature because they make much lower HP so it was never needed? jimboF4
 

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Hi Adam, I assume that the 750 models do not have this feature because they make much lower HP so it was never needed? jimboF4
The 750 had a similar problem that I think they addressed in a similar way, on very early 750's it was very hard to re open the throttle mid corner at 6000-7000rpm, the engine vacuum was pulling the throttle blades closed, so, on the 1000 they retarded the ignition which allowed them to open the throttle blades further at idle which helped the issue at 6-7K :)
 

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Discussion Starter #10 (Edited)
The advance is retarded according to the speed of the rpm rising, very slow and there is a lot less retard.
See the 2 graphs below.

in gear vs neutral on both charts.
1st chart is rpms rising in 500ms, note, more retard...
2nd is rpms rising in 1500ms.

Green trace is the rpm, dark blue the advance

I think this will mean the throttle should be no more sensitive if the tables were changed.
Anyhow, I could always just set them half way !

The main question however is why did MV do this in the first place. Are there other reasons you would want to strangle the engine low down ?

Jimbo, there is no ecu connection to the neutral switch on the 750

Cheers
Adam
 

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Adam,

The only reasons they retarded the timing at low RPM, that I could think of anyway, would be to soften the power delivery down low, and as mentioned keep the throttle blades a bit farther open to help the transition to back on the throttle in mid corner. Noel has mentioned this many times here, and it makes sense.

He's also correctly said that retarded timing is one of the reasons these bikes run hot. My bike runs much cooler at higher RPM than it does when I'm short shifting and keeping the revs around 3-5k. I'm certain that a lot of that is because of the timing being so retarded at those revs.

I've also wondered about the Microtec Chris at X-Bikes has for the 1000 S model, and how it deals with these issues, as well as the EBS function. Anyone know?

Thanks,

John
 

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Chris has the Microtech tuned to different advance curves from MV standard. He also has reset EBS function, fan cut-on temp, etc.
You should contact him to discuss, he has spent a lot of time developing mapping for the Microtech and MVs.

Just wish I could afford one!
 

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Discussion Starter #13 (Edited)
I also have different advance curves to MV standard, different fueling, fan temps, EBS table and lower limit settings etc.
I spent a lot of road and dyno time tuning it, Chris probably spent 10 times more !
He won't want to give anything away but maybe he knows a reason for the retarding.
I remember he tried shorting out the neutral switch to stay on once but it poped and banged all over the place - I know your reading this Chris / Donsy ;)

The EBS on the microtec will always be better.
On the 16M, the EBS solenoid is either on or off, the Microtec uses pulse width modulation so it can smoothly switch the solenoid from on to off in many steps and keep it just partially on.

John, why bother writing extra coding to only retard the advance when in gear and switch it when in neutral. The 750 doesn't have this function - I'll check the off throttle advance settings on it though..

If it is because of the throttle blades then why not retard it in neutral as well and not bother with the coding ?

Cheers
Adam
 

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Chris has the Microtech tuned to different advance curves from MV standard. He also has reset EBS function, fan cut-on temp, etc.
You should contact him to discuss, he has spent a lot of time developing mapping for the Microtech and MVs.

Just wish I could afford one!
I'm with you there, Ed. I'd like to have one of Chris's set-up Microtec units for the 312R. I'm not sure if he does a unit for the late (Evo 3) 750s. I know Merc07 has done a bit. I guess I have to get up to speed now on the 1.6M ECU.
 

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The advance is retarded according to the speed of the rpm rising, very slow and there is a lot less retard.
See the 2 graphs below.

in gear vs neutral on both charts.
1st chart is rpms rising in 500ms, note, more retard...
2nd is rpms rising in 1500ms.

Green trace is the rpm, dark blue the advance

I think this will mean the throttle should be no more sensitive if the tables were changed.
Anyhow, I could always just set them half way !

The main question however is why did MV do this in the first place. Are there other reasons you would want to strangle the engine low down ?

Jimbo, there is no ecu connection to the neutral switch on the 750

Cheers
Adam
I suspect just for low down manners! Like I said in my write up if you get the rpm's wrong when trying a quick take off the bike rears up very quickly, or did do! I wrote that in 2005
 

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OK, folks lets try this again

go LOOK down your throttles, what do you see????

the BIG side of the throttle blade is to the rear right, on the 'uphill' side, right?

unlike any other throttles I have ever seen:wtf:

what happens when there is high manifold vacuum, like under hard decel? atmospheric pressure put more force on the big side and the throttle sticks...see why? you put the big side on the 'downhill' side and atmospheric pressure helps open the throttle

Magnetti Marelli screwed up plain and simple, they are built backwards

how do you reduce engine vacuum?

you retard it, what is the consequence of retarding a motor????

it runs hot:jsm:......sound like an MV???? no shit

a 1000S is -4 deg initial, a 1000R is -10 deg initial.....which over heats more?

very few injected bikes reference manifold pressure......try flying a piston powered airplane without it......you set takeoff power with manifold pressure!

go find an old VW bug and disconnect the vacuum advance.....what happens?

runs like shit and sucks fuel right?

my '08 910R gets 19MPG around town and 37MPG at 85MPH, the '02 R1150 GS gets the same 37MPG at 85MPH

whats that tell you? an Alpha/N system sucks:naughty:

my old R750/5 got 57MPG at 115MPH.....with vacuum slide carbs, PSST it takes more HP to go 115 than 85

now the rice rocketeers......twin throttles????? give me a break, what for??

Ed said it was to cure 'low speed gasp', what their FI guys are that incompetent???? :wtf:

remember accelerator pumps?

in FI its Delta/Alpha or the rate of change of TPS

in FI you can do temperature compensation on the separate "accelerator pump squirt" and no, it doesn't have to be synchronous, so don't get all upset about duty cycle:laughing:

the real problem?

motorcycle manufacturers won't spend the money to hire someone that knows what they are doing, either because they are too cheap, incompetent, or too egotistical, take your pick

the head guy from Pectel is $1000 a day (the Pectel SQ-6M was developed by Cosworth)
 

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F41000R also has a retard at idle, when the bike is at idle the timing is fixed at 10ATDC, for those with a 1000R and maybe a 312, when you try and lift the RPM slightly with the twistgrip it won't rise whilst the throttle is showing 0 degrees on the diagnostic read out.
You open it slightly more and more and still no rise in rpm, then as soon as the throttle opening gets to 2.5 degrees the rpm will jump to about 2000 rpm and the timing is then 'free' in so much as it hunts around a little as you would expect.

And for Merc, i have no idea if this also does the retard stuff when compared to the neutral switch.................But I would guess it doesn't :)
 

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I'll come back to this as I've got two deadlines to hit today and tomorrow but sometime in between I'll add to this.


ciao ;)
 

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Discussion Starter #19 (Edited)
OK knurl but the question is why the switch between neutral and in gear, why not just use the same table ?

No one spotted my deliberate mistake in the simulation then ?
All RPMs were rising from start to end in 500ms, that means 1000 - 5000 rpm simulation was actually quicker / more tps than the 1000 - 2000 rpm rise, hence the extra retartd maybe? I'll adjust the times accordingly and go from there.
The retard table is more linear which would make sense.

Meanwhile, i'll sit back and wait for more input from Chris....



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now the rice rocketeers......twin throttles????? give me a break, what for??

Ed said it was to cure 'low speed gasp', what their FI guys are that incompetent???? :wtf:
Most Japanese bikes (all modern Suzukis) use manifold pressure as one of 3 primary inputs for the EFI maps. The other 2 are TPS and RPM. They are quite sophisticated systems, much more advanced than the antique 16M ECU and even the newer Marellis that MV used....I don't know about the new Eldor systems.

The secondary throttle plates on Suzukis are controlled by the ECU to compensate for sudden changes of MAP when the throttle is "wacked" open...same concept as a CV Carburetor. They are also utilized to provide alternate "Ride Modes" on some bikes, reducing power for rainy conditions, etc.

The Ride-By-Wire systems now becoming popular achieve the same affect by the ECU controlling the primary throttle plates instead of your right wrist. Unfortunately, when they fail you have no control and the bike goes to a "fail safe" (can't ride) mode. At least with the Suzuki design you can still get home.

Racers take out the secondary throttle plate because they have no interest in anything less than wide open...they aren't riding on the street in traffic...or basically for the same reasons most race bikes never used CV Carbs.

Noel, you know what happens to manifold pressure and fuel mixture when you abruptly open a throttle plate fully from a very low RPM. So you know that optimum power can be achieved by controlling the manifold pressure at a proper level for best performance in those conditions.

I'm pretty sure the FI engineers in Japan and Europe know exactly what they are doing. Technology marches on.
 
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