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Oooo baby Enzofour  - but beginner on fueling? 
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My Italian is a little rusty, but this does not look good.
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(05-25-2022, 08:01 PM)Enzofour_imp Wrote: (05-24-2022, 06:04 AM)max_imp Wrote: Enzo there are 4 calibrated gauges required together with the knowledge to deal with the interaction of the iacv positions.
From the question i think you may not have done a carb/ throttle body sync before, so before changing anything i would suggest to watch several yt video's to find out what's involved, how to do it and why.
Throttle sync is only required when the engine is warm and at idle, there is no other reason to adjust the sync adjustment which is why Honda does not supply service info, they want to avoid the risk of getting it wrong which is easy to do, the adjustment screws are not fixed like the old carburettors so by adjusting too much you can drift out of range and end up with a rich or lean mixture.
With carburetors you adjust the amount of fuel mixture, with a throttle body you only adjust the amount of air per cylinder, there is a difference.
For instance when i bought my cb919 the engine sounded like a harley at idle, the engine only ran on 2 cylinders, it took me a while to work out why, and after syncing the throttlebody with the 4 gauges it started to run like it should have; somebody mis-understood what they did and got it wrong.
Once i had the vacuum gauges installed and started the engine it was very apparent that the sync was off.
All four cylinders have the same capacity so they produce the same amount of vacuum at each intake stroke at the intake when the valves open, this amount can be measured with 4 individual vacuum gauges and adjusted so they read the SAME amount of vacuum supplied through the iacv and adjusted ( equalized ) by the 4 screws under the throttle body.
As soon as the throttle is opened slightly the butterfly valves and the tps start doing their job and the idle screws are no longer of any importance, they are only required when the butterfly valves are closed.
You can then verify this by using a piezo electric pressure sensor in the exhaust and watch the pulses it produces with each exhaust stroke which should be equally the SAME, you do need an automotive oscilloscope for this check so you can record and watch the pulse train.
Hope this helps.
My advice; if there is no problem don't introduce one.
With all respect for your ability and thanks for all your help, i appreciate it; cheers
Ciao Max, come puoi vedere non sono proprio un principiante 
![[Image: 5efde316e31cb5dc6054cfb30e34aa9c.jpg]](https://cb1100forum.net/forum/uploads/imp/202205/5efde316e31cb5dc6054cfb30e34aa9c.jpg)
Ma questo era un motore a carburatori, sui corpi farfallati si sono un principiante.
Il mio CB1100 non ha problemi, ma vorrei sapere dove precisamente collegare i tubi del vacuometro perche ci sono diversi tubi sul corpo farfallato e non vorrei sbagliare.
Mi piacerebbe controllare se le leggere vibrazioni al manubrio e agli specchi, che ho a motore caldo e in folle, sono fisiologiche o è il minimo non perfettamente alliniato.
Enzo, I'd like to know if this engine was taken apart for rebuilding or something else.
Nice, clean and well organized garage / 5*
...
Enzo, vorrei sapere se questo motore è stato smontato per la ricostruzione o qualcos'altro.
Garage bello, pulito e ben organizzato / 5*:
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I think Enzo should leave it outlaid as is to showcase the beauty that all is inside the lump.
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I don't know what he said- but anyone able and willing to take the engine apart that far will probably be able and appreciate the advanced capabilities and charting of this for syncing-
http://cb1100forum.com/forum/showthread.php?tid=16275
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(05-26-2022, 08:13 AM)PowerDubs_imp Wrote: I don't know what he said- but anyone able and willing to take the engine apart that far will probably be able and appreciate the advanced capabilities and charting of this for syncing-
http://cb1100forum.com/forum/showthread.php?tid=16275
(+1)
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(05-23-2022, 09:19 AM)whizzle_dizzler_imp Wrote: Yeah, I just read their returns page.
I follow ya.
I am hoping the ECU solves your (and mine) problem. I hope you will keep us informed. I tried cleaning the TPS contacts the other day and my 2000rpm dropped to 1500, for what it is worth.
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So, anybody trash the fuel injection and replace with carburetors yet ?
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(05-27-2022, 08:50 PM)riceburner_imp Wrote: So, anybody trash the fuel injection and replace with carburetors yet ?
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(05-26-2022, 07:41 AM)peterbaron_imp Wrote: (05-25-2022, 08:01 PM)Enzofour_imp Wrote: (05-24-2022, 06:04 AM)max_imp Wrote: Enzo there are 4 calibrated gauges required together with the knowledge to deal with the interaction of the iacv positions.
From the question i think you may not have done a carb/ throttle body sync before, so before changing anything i would suggest to watch several yt video's to find out what's involved, how to do it and why.
Throttle sync is only required when the engine is warm and at idle, there is no other reason to adjust the sync adjustment which is why Honda does not supply service info, they want to avoid the risk of getting it wrong which is easy to do, the adjustment screws are not fixed like the old carburettors so by adjusting too much you can drift out of range and end up with a rich or lean mixture.
With carburetors you adjust the amount of fuel mixture, with a throttle body you only adjust the amount of air per cylinder, there is a difference.
For instance when i bought my cb919 the engine sounded like a harley at idle, the engine only ran on 2 cylinders, it took me a while to work out why, and after syncing the throttlebody with the 4 gauges it started to run like it should have; somebody mis-understood what they did and got it wrong.
Once i had the vacuum gauges installed and started the engine it was very apparent that the sync was off.
All four cylinders have the same capacity so they produce the same amount of vacuum at each intake stroke at the intake when the valves open, this amount can be measured with 4 individual vacuum gauges and adjusted so they read the SAME amount of vacuum supplied through the iacv and adjusted ( equalized ) by the 4 screws under the throttle body.
As soon as the throttle is opened slightly the butterfly valves and the tps start doing their job and the idle screws are no longer of any importance, they are only required when the butterfly valves are closed.
You can then verify this by using a piezo electric pressure sensor in the exhaust and watch the pulses it produces with each exhaust stroke which should be equally the SAME, you do need an automotive oscilloscope for this check so you can record and watch the pulse train.
Hope this helps.
My advice; if there is no problem don't introduce one.
With all respect for your ability and thanks for all your help, i appreciate it; cheers
Ciao Max, come puoi vedere non sono proprio un principiante
Ma questo era un motore a carburatori, sui corpi farfallati si sono un principiante.
Il mio CB1100 non ha problemi, ma vorrei sapere dove precisamente collegare i tubi del vacuometro perche ci sono diversi tubi sul corpo farfallato e non vorrei sbagliare.
Mi piacerebbe controllare se le leggere vibrazioni al manubrio e agli specchi, che ho a motore caldo e in folle, sono fisiologiche o è il minimo non perfettamente alliniato.
Enzo, I'd like to know if this engine was taken apart for rebuilding or something else.
Nice, clean and well organized garage / 5*
...
Enzo, vorrei sapere se questo motore è stato smontato per la ricostruzione o qualcos'altro.
Garage bello, pulito e ben organizzato / 5*:
Enzo, I'd like to know if this engine was taken apart for rebuilding or something else.
Nice, clean and well organized garage / 5*
...
Enzo, vorrei sapere se questo motore è stato smontato per la ricostruzione o qualcos'altro.
Garage bello, pulito e ben organizzato / 5*:
Disassembled for reconstruction
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CB1100 Idle speed instability problem
