Need help/instructions on Throttle Body cleanup

[Kev m]

Hey Kev. Did I say EFI? NO I said I have put a manual petcock on bikes that had an electrical one, guessing you have electric one?
Before you or someone else jumps to any conclusions, I am NOT referring to the Titanic, the Hindenburg, Starship Enterprise, or MH370.

Ok, I'll try this again. I don't have any petcocks on any of my current bikes and haven't had one since the 2000 Jackal (which I did indeed change from electric to manual).

But the OP asked about cleaning throttle bodies. That means EFI.

The OP has a Breva and like most Guzzis that means EFI AND NO PETCOCK.

So he doesn't have a manual or electric petcock.

As for electric petcocks, has there ever been a carbureted bike with one? (Like did the carbureted Calis use one? That's before my time with Guzzis so I'm genuinely asking and interested to hear the answer).

But that's a tangent, as this thread is about an EFI smallblock with two throttle bodies, an internal tank fuel pump, no petcock and manual fast idle linkage (so no electronic idle air    control circuit).

I get that you're trying to help, but it's really easy to confuse guys who are new to this stuff and asking these questions. So I'm not complaining about your contribution, but I am trying to clarify for those who don't know the difference.

No offense meant whatsoever.

[yogidozer]

Ok, I'll try this again. I don't have any petcocks on any of my current bikes and haven't had one since the 2000 Jackal (which I did indeed change from electric to manual).

But the OP asked about cleaning throttle bodies. That means EFI.

The OP has a Breva and like most Guzzis that means EFI AND NO PETCOCK.

So he doesn't have a manual or electric petcock.

As for electric petcocks, has there ever been a carbureted bike with one? (Like did the carbureted Calis use one? That's before my time with Guzzis so I'm genuinely asking and interested to hear the answer).

But that's a tangent, as this thread is about an EFI smallblock with two throttle bodies, an internal tank fuel pump, no petcock and manual fast idle linkage (so no electronic idle air    control circuit).

I get that you're trying to help, but it's really easy to confuse guys who are new to this stuff and asking these questions. So I'm not complaining about your contribution, but I am trying to clarify for those who don't know the difference.

No offense meant whatsoever.

OK Kev, I'll type this slow for you.
I have put a manual petcock on bikes that had an electrical one, guessing you have electric one?
My EV HAS EFI....AND AN ELECTRIC PETCOCK ORIGINALLY.
Never said I had the same bike the OP has, hence the part....guessing you have electric one?
Lay off the Buds and get youself some cranberry juice 

[Ncdan]

Easy guys. We are all on the same team here and just trying to assist a fellow member with an issue👍

[Kev m]

OK Kev, I'll type this slow for you.
I have put a manual petcock on bikes that had an electrical one, guessing you have electric one?
My EV HAS EFI....AND AN ELECTRIC PETCOCK ORIGINALLY.
Never said I had the same bike the OP has, hence the part....guessing you have electric one?
Lay off the Buds and get youself some cranberry juice 

I tried politely explaining multiple times.

So I'll try being direct. Your information was completely irrelevant to this thread.

No one here that doesn't have an old Cali has ANY KIND OF PETCOCK. Like I directly said again and again I don't, OP doesn't, anyone with a Breva of any kind, or any CARC, or a Cali from the past couple of decades, or a V9, or V85, none of us.

You're guessing wrong.

Your information is not helpful.

It's has nothing to do with what any of us are talking about.

I literally cannot believe you can't understand it with all the patient explanations I've offered.

I'm completely stumped why you can't grasp this.

I'm not in the slightest but offended.

I just can't grasp why you seemingly can't understand this or are otherwise choosing to be deliberately obtuse.

[yogidozer]

I tried politely explaining multiple times.

So I'll try being direct. Your information was completely irrelevant to this thread.

No one here that doesn't have an old Cali has ANY KIND OF PETCOCK. Like I directly said again and again I don't, OP doesn't, anyone with a Breva of any kind, or any CARC, or a Cali from the past couple of decades, or a V9, or V85, none of us.

You're guessing wrong.

Your information is not helpful.

It's has nothing to do with what any of us are talking about.

I literally cannot believe you can't understand it with all the patient explanations I've offered.

I'm completely stumped why you can't grasp this.

I'm not in the slightest but offended.

I just can't grasp why you seemingly can't understand this or are otherwise choosing to be deliberately obtuse.

My information was to use Seafoam. I also suggested to drain gas from the tank. I drain from the petcock, on my EV and Sport 1100.
As I stated I DO NOT KNOW IF HIS BIKE HAD ONE.

[Kev m]

My information was to use Seafoam. I also suggested to drain gas from the tank. I drain from the petcock, on my EV and Sport 1100.
As I stated I DO NOT KNOW IF HIS BIKE HAD ONE.

Seafoam or drain was actually useful. Sorry it got lost in all the other noise.

Maybe it wouldn't have if you hadn't double-downed on the other crap, repeatedly.

[yogidozer]

Seafoam or drain was actually useful. Sorry it got lost in all the other noise.

Maybe it wouldn't have if you hadn't double-downed on the other crap, repeatedly.

Guess reading isn't your strong point. Still waiting for you to show me where I said HE has an electric petcock, or any petcock

[Kev m]

Guess reading isn't your strong point. Still waiting for you to show me where I said HE has an electric petcock, or any petcock

Right here, literally:

I have put a manual petcock on bikes that had an electrical one, guessing you have electric one?
Siphon gas into a gas can, set the bike on the sidestand, drain

< Snip >
Get rid of the electric petcock some day, then you can drain right from the petcock..

That is what sent us down this path. And I wasn't the only one to note it.

All I did was try to clarify that this didn't apply. And then tried multiple times to explain WHY this was wrong/misleading/confusing/inaccurate.

My intention was never to insult.

I tap danced trying to be nice.

I have still not taken a direct swipe at you.

Please READ this simple answer in the intent it is met. To clarify and not insult.

[MotoGuzzi750]

I can't help much but I can add that I was always surprised how much a new air filter improved the way the bike runs - sufficient to say that I track the change interval religiously and don't hesitate to do it a little early.

Took out the air filter, and it is very old and dirty !
I should have done this earlier I feel.
New air filter has has arrived and will install it soon.

I decided to drive without any air filter while waiting for the new one to be delivered.
And I am very happy with the results.
The engine doesn’t feel like it wants to die at stop.
Rpm stays close to 1000.

I noticed that rpm drops slightly below 1000 after driving for about 20-30 mins.
I am curious to know why does this happen.
It doesn’t prevent me from driving presently, just curious to know.

Hoping good results with new air filter…

Thanks.

[guzzisteve]

Well, you are getting some results. Good. Clean out airbox & put in new filter. You should monitor the spark plug color after running it, if plugs are getting dark or light. Open airscrews a tad if getting dark & running slower from it(leaning out mixture up to around 2500rpm).
CycleTrader has a Griso 1100 over here in SC for $3500 for sale if you are still looking.

[lucky phil]

Took out the air filter, and it is very old and dirty !
I should have done this earlier I feel.
New air filter has has arrived and will install it soon.

I decided to drive without any air filter while waiting for the new one to be delivered.
And I am very happy with the results.
The engine doesn’t feel like it wants to die at stop.
Rpm stays close to 1000.

I noticed that rpm drops slightly below 1000 after driving for about 20-30 mins.
I am curious to know why does this happen.
It doesn’t prevent me from driving presently, just curious to know.

Hoping good results with new air filter…

Thanks.

Maybe it needs to idle a fraction higher. The true idle is probably slightly lower than that indicated.

Ciao

[Kev m]

OP - not assuming any level of knowledge here so please excuse if I'm covering basics you already knew.

When mechanical adjustments are available for idle speeds, they are set to meet spec at hot idle as that is the condition that is most used.

But because of mechanical differences in conditions the setting for hot idle would not be sufficient for cold idle.

As such motors have methods of making up the difference to force a fast cold idle until the engine is warmed.

Carbs use things like chokes or enrichener circuits (two different ways around a square, that end in the same place, with a richer air/fuel ratio). This allows for easier cold starts and for a steady (albeit faster idle when cold). Actually the same amount of enrichment means for a VERY fast idle when warm.

EFI motors automatically adjust the air/fuel ratio for conditions like cylinder head and ambient temperature. But this may not be enough to keep the engine running steadily when cold, so they ALSO use some method of introducing more air for a faster idle. Many (most?) use an IAC (idle air control valve) to bypass the standard throttle plate position (which is closed/almost closed at idle). Others, like the 2TB smallblocks use a manual throttle advance knob (probably labelled choke, even though it doesn't actually choke anything) to physically open the throttle plates the smallest additional amount introducing more air and producing a faster idle).

Anyway that's just a long way of saying that if all else is in good condition (valves, spark plugs, clean intake and passages) then a linkage or air screw adjustment is necessary to set the idle properly when the engine is fully warmed.

I don't remember if the 2TB models had an adjustable TPS or not. The TPS (throttle position switch) is a potentiometer that tells the ECU how open or closed the throttle is at any given moment. As such it is a critical component to any speed/density EFI air/fuel ratio calculation. I mention this because on my Cali Jackal years back, after say 30-40k miles I developed a slightly slow hot engine idle that allowed it to stall a few times. After checking the basics I determined that the fix was to tweak the TPS setting ever so slightly and it returned to perfect idle after the incredibly minor adjustment. I'm not sure if this is a possible issue on your smallblock or not, but if it is then it would be one of the very last things you'd check anyway. If your TPS isn't adjustable (physically or electronically), then just bank it as totally irrelevant to this bike.

Hope some information here helps.

[guzzisteve]

From the Breva Service Manual---------------"Execute the throttle position self-teach procedure"------------- You need some software for this.
This could also solve your low idle issue.

[Kev m]

From the Breva Service Manual---------------"Execute the throttle position self-teach procedure"------------- You need some software for this.
This could also solve your low idle issue.

 

Ah electronic - got it. So the ECU learns the idle closed position and resets the value. Copy! Same as CARC and later bikes then.

[guzzisteve]

Been a while eh Kev? Didn't you have a V7C? When I went out to Cost Mesa for refresh on new models it was almost new. Manuals are made cause you can not remember all this stuff, only the stuff that doesn't change.

[Kev m]

Been a while eh Kev? Didn't you have a V7C? When I went out to Cost Mesa for refresh on new models it was almost new. Manuals are made cause you can not remember all this stuff, only the stuff that doesn't change.

No my Stone is MY first smallblock, though my little bro Jay's first one was a V7C.

[MotoGuzzi750]

From the Breva Service Manual---------------"Execute the throttle position self-teach procedure"------------- You need some software for this.
This could also solve your low idle issue.

I don’t have service manual for Breva.
How do I get it ?
Also would you recommend to execute this working/checking on valve clearance and spark plugs checks?
I would think so.

Thanks.

[Kev m]

I don’t have service manual for Breva.
How do I get it ?
Also would you recommend to execute this working/checking on valve clearance and spark plugs checks?
I would think so.

Thanks.

I don't think you necessarily need the Breva manual, though the engine content would probably be useful.

He was just using it as a reference that the TPS is not mechanically adjustable on the twin-throttle body models like the Breva and the V7C.

I have the V7C Service manual PDF which was published in 2008. If you need it PM me an email address and I'll send it out. I don't think it will need to be zipped or anything.

As for resetting the TPS, I don't think it is necessary anytime you set the valves or change the plugs, but in theory it would be necessary after any linkage adjustments or throttle body synchronization. It isn't a bad idea though if you continue to have low idle and you are sure everything else is mechanically in good condition.

[guzzisteve]

Hey 750, here's the manual, just click on it and download the PDF-----------------------------------------------------

https://guzzitek.org/gb/ma_us_uk/750/Breva750IE_042003_Atel(GB).pdf

Good Luck----------------------------

[Kev m]

Hey 750, here's the manual, just click on it and download the PDF-----------------------------------------------------

https://guzzitek.org/gb/ma_us_uk/750/Breva750IE_042003_Atel(GB).pdf

Good Luck----------------------------

Steve, does the B750 manual have some stuff that the later V7C manual doesn't?  Just curious.

[guzzisteve]

Yes, pretty much same bike just different bodywork, bars, etc and the Nevada is same too.

[Kev m]

Yes, pretty much same bike just different bodywork, bars, etc and the Nevada is same too.

Yeah I know that, but IIRC the Breva book was published in maybe 2003 and the V7C book in 2008 so unless the V7C was just a supplement to the Breva book I would expect some changes/differences.

I was asking if you knew if anything was superseded.

No big as I don't have a 2TB smallblock, but you never know when you might have to work on one so I was curious.

[guzzisteve]

Same stuff all those years all the way to the single throttle body. Except for covers Around 10yrs no changes. The wear plate on the crank is probably from 1978, if it works they didn't change anything.

[Kev m]

Same stuff all those years all the way to the single throttle body. Except for covers Around 10yrs no changes. The wear plate on the crank is probably from 1978, if it works they didn't change anything.

 

Thanks

[MotoGuzzi750]

Have you tried Seafoam?

Since Seafoam is working well, I am wondering if cleaning the fuel injectors may also help.
What do you think about that? And also, what is the procedure to follow to clean fuel injectors on this model?

[MotoGuzzi750]

I can't help much but I can add that I was always surprised how much a new air filter improved the way the bike runs - sufficient to say that I track the change interval religiously and don't hesitate to do it a little early.

I will be installing new air filter soon ( currently running bike without any air filter for short/ocassional rides ).

Since adding Seafood to gas tank has helped run better, I would like to know if fuel injectors are clogged?
What do you think? How hard/easy it is clean them? What is the procedure to clean them? -Thanks.