Author Topic: Sacred Screw Reset  (Read 6346 times)

Offline GonzoB

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Re: Sacred Screw Reset
« Reply #60 on: December 14, 2020, 01:25:45 AM »
Hi Roy.

This is why I hesitated in making comment....

It's entirely possible that the flow characteristics (eg laminar or turbulent flow) won't change with changing the fluid. The last thing you would want is to have a flow rate that is right on the border between different flow types. If you had that, then the results would be likely to vary with very small changes in adjustment. All I'm saying is that Roy's design is close to maintaining the same Re number, and that's a good starting point.

Until these methods are tested by installing and running an adjusted throttle body we won't know.

I can be (quite fairly) accused of over-thinking this, but it does add some rigor to the discussion.

Gonzo
My '07 Breva 750 Projects: MCC cruise - Luggage - Shorter Shocks -

Offline Huzo

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Re: Sacred Screw Reset
« Reply #61 on: December 14, 2020, 01:32:20 AM »
Damn right.. :thumb:

Offline Kiwi_Roy

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Re: Sacred Screw Reset
« Reply #62 on: December 14, 2020, 05:58:10 AM »
Don't get me wrong I enjoy trying to figure out what you guys are talking about.
I do think you are over thinking it but that's ok sooner or later you will make your own rig and find out its not all theory.
Just let me know when you are ready to startup on Gasoline or Methanol and I will take cover lol
 
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Offline arci

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Re: Sacred Screw Reset
« Reply #63 on: July 22, 2021, 07:13:22 AM »
One question. Is it possible to use TPS sensor PF3C and set 150 mV at zero TPS position and after it set the 4.7 TPS position by corresponding voltage?

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Re: Sacred Screw Reset
« Reply #63 on: July 22, 2021, 07:13:22 AM »

Offline guzzisteve

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Re: Sacred Screw Reset
« Reply #64 on: July 22, 2021, 10:19:30 AM »
Well, John Jibell over on the GT forum says NO. I tend to agree w/him. You need a different ECU for that work.
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Online Mayor_of_BBQ

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Re: Sacred Screw Reset
« Reply #65 on: July 22, 2021, 12:53:23 PM »
I read most of this, understood essentially none of it


I'm not even clear what you gents are trying to do but it seems impressive
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Offline Kiwi_Roy

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Re: Sacred Screw Reset
« Reply #66 on: July 22, 2021, 02:53:46 PM »
I read most of this, understood essentially none of it


I'm not even clear what you gents are trying to do but it seems impressive
It's quite simple really,
The Throttle bodies get out of whack when someone thinks that's the way to set the idle speed, it throws the mixture out the window.
What we need to do is re-set the throttle stop on a messed with throttle body so it passes the correct amount of air.
If we have a good unit and measure the flow through that its a simple matter of matching the flow of the bad unit to the good unit
Since we have no way of measuring the air flow we use water, we don't need to convert water flow to air flow because for any given opening if the pressure is constant the flow will be constant also unlike air, water is very easy to measure by weight or volume/Time
This is something control valve manufacturers have been doing for ever, they talk in cV the quantity of water that will flow in one minute at 1 psi
In this case we just need to set a molested throttle body to flow the same an un-molested one, if they both flow the same quantity of water it goes without saying they will also flow the same amount of air.
In theory someone could take the numbers I found and make a rig to set his throttle body to match mine.
His rig could look quite different, it only has one important dimension and thats the height of water over the butterfly, the pipe diameter could be quite different within reason.
I spent many years specifying control valves for chemical plants, I'm just trying to find a practical use for that experience.
I only had one throttle body to work with, the one on my Griso which still had the original paint sealing the screw.
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Offline Kiwi Dave

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Re: Sacred Screw Reset
« Reply #67 on: July 22, 2021, 04:00:59 PM »

Offline guzzisteve

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Re: Sacred Screw Reset
« Reply #68 on: July 22, 2021, 04:42:26 PM »
The guy who resurrected the thread wants to use stuff from both but later ecu for a stepper.

Why not take stepper off, plug holes, and never reset tps, move magic screw anywhere BUT never reset it. You can put it back w/o an issue. It is only after re-setting to what ever is normal that it gets out of wack.
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Offline arci

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Re: Sacred Screw Reset
« Reply #69 on: September 02, 2022, 02:19:58 AM »
TPS sensor PF1C is linear TPS sensor, in this case we are able to set 4.7° as difference value.

In this case should work the process:
- For the reset, find the absolute closed position (point where it stops moving closed) hit reset TPS button.
- turn screw till software says 9.4*, hit reset TPS button. (9.4/2=4.7)
- It is set to 4.7°

Offline guzzisteve

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Re: Sacred Screw Reset
« Reply #70 on: September 02, 2022, 10:31:40 AM »
Yes, That's how it's done. I've had to fix a few but not many. You need clean throttle bodies and have to find that point where it just touches closed.
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Offline lucian

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Re: Sacred Screw Reset
« Reply #71 on: September 03, 2022, 07:33:28 AM »
TPS sensor PF1C is linear TPS sensor, in this case we are able to set 4.7° as difference value.

In this case should work the process:
- For the reset, find the absolute closed position (point where it stops moving closed) hit reset TPS button.
- turn screw till software says 9.4*, hit reset TPS button. (9.4/2=4.7)
- It is set to 4.7°

  The problem with this is that 4.7degrees TPS is an angular measurement as related to the axis of the throttle plate pivot . When backing off the stop screw until no more movement closed is detected, the throttle plate will not be at O degrees. It does not close absolutely perpendicular to the  throttle body bore.

Online Wayne Orwig

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Re: Sacred Screw Reset
« Reply #72 on: September 03, 2022, 08:26:32 AM »
TPS sensor PF1C is linear TPS sensor, in this case we are able to set 4.7° as difference value.

In this case should work the process:
- For the reset, find the absolute closed position (point where it stops moving closed) hit reset TPS button.
- turn screw till software says 9.4*, hit reset TPS button. (9.4/2=4.7)
- It is set to 4.7°

The TPS is on the right throttle body, through the linkage.
The sacred screw is for the left throttle body.
So the linkage adjustment would mess with that reading, correct?
« Last Edit: September 03, 2022, 08:25:17 PM by Wayne Orwig »
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Offline guzzisteve

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Re: Sacred Screw Reset
« Reply #73 on: September 03, 2022, 08:30:40 AM »
I converted it to voltage @ closed, then reset it at the correct voltage for 4.7* manually then reset it. They do not all come perfect from factory. If you balance the TB's at 4K and idle is to high when you get done, you are past the allowance they leave you. Not much else you can do but turn it down from stock.
The important thing if you have this situation is you do not reset it after moving it manually. You leave it alone so you know where you are in degrees. It will fuel fine w/o being reset.
It's best not to mess w/it at all, BUT do you want a bike that runs out of TB sync and always rough.
Most of the time it is the stepper or clutch switch. Steppers are way up in price so you delete it.
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