VDSTS won't open. (resetting TPS for closed throttle))

[John in PA]

Trying to reset TPS zero after rebalancing TB's on a buddy's new Stelvio (dealer couldn't be bothered, apparently).. I'm using the version of the software from Technoresearch, from when Giamberto was still there. 3.0x version. Been a while since I used the VDSTS. This is a 2014 Stelvio NTX. is it still the 5AM or 5AW computer as on the early 2009 Stelvios, (which mine is)

Anyway software says there's no hardware key or missing driver. this is the version using the Keyspan USB/ serial adapter. I also have the old USB hardware key,from a previous version, but my recollection was that with the Keyspan, I didn't need the key. Anyhow, I tried it with and without the extra key and get the same message. I also reinstalled keyspan driver eventhough it supposedly was present.

What am I doing wrong?

I could also use a link to the procedure for resetting TPS zreo after a TB rebalance as it's been quite a while since I did it.

 

[GTM®]

John, give TR a ring and ask for Sandro or technical help. If it's long distance, have them call you back (they will). They're generally happy to guide you through all of it; 248.658.1800 - 9-5 CST (MI).

 

[John in PA]

Thanks, Todd! After rebalancing, all I should have to do is reset the TPS, correct?

After balancing TB's, idle speed climbed too high (maybe around 1400) , probably due to the TB with the sensor being the one that was adjusted, with concurrent timing advance, is what I'm thinking.

 

[GTM®]

Thanks, Todd! After rebalancing, all I should have to do is reset the TPS, correct?

After balancing TB's, idle speed climbed too high (maybe around 1400) , probably due to the TB with the sensor being the one that was adjusted, with concurrent timing advance, is what I'm thinking.

Correct, only a TPS reset. If you balanced the left side, that will raise the idle. Set it back to where it was (if you can), and adjust the right side accordingly. Timing is not affected.

 

[John in PA]

My recollection on balancing method is that the throttle stops left and right are only for balancing at idle and the adjuster screw in the independent linkage on the left lower front of the left TB is the one to use for all balancing for throttle settings above idle. In this case, owner was complaining of excessive vibration in the band from 3000-4000 RPM, which I interpreted as bad throttle balance (corrected per the TwinMax).

You'd have to back off both throttle stops to get RPM's to drop and maintain balance at idle, or else I'm missing something.(??) Plus, I think the computer resets idle speed with the TPS reset, doesn't it?

Just been while since I monkeyed with this, and want top be sure I remembered correctly.

 

[john zibell]

Do not touch the throttle stops. That will mess up the fuel injection system. The throttle stop is the "sacred screw" referenced in the VDSTS thread. If moved the method to get the butterfly at the correct degree of opening on fixed (non moveable) TPS bike is to replace the TB the TPS is mounted to. The TPS and butterly can be reset on 15M bikes, but not 5AM and 15RC machines. If the idle is high, there is another issue, stepper motor, vacuum leak or something along those lines. The new bikes are designed to idle higher (1150 to 1250 or so) as read by software, not the bike tach as those are not too reliable.

 

[John in PA]

I got the software to open by reinstalling the driver software for the hardware key. Went into Device Manager in Windows, found the correct USB device and reinstalled driver. I tested it on my bike and reminded myself how everything works.

And, TPS CAN be reset in the IAW5AM computer, but it's done automatically by the software. But, it's NOT done by touching the throttle stops. The TPS reset is done if, after balancing throttles, the closed throttle reading is anything other than 4.7mV. If that's the case, you tell the computer to reset TPS and basically it tells the computer that the "NEW" setting IS 4.7mV. Essentially tells the computer *where* zero throttle is, and it references from there.

Anyhow, now I should be able to get my buddy's bike reset and ready to enjoy.

 

[john zibell]

You'd have to back off both throttle stops to get RPM's to drop and maintain balance at idle, or else I'm missing something.(??) Plus, I think the computer resets idle speed with the TPS reset, doesn't it?

Just been while since I monkeyed with this, and want top be sure I remembered correctly.

Since you mentioned backing off the screws here I thought I'd remind you not to do that to save the expense of a throttle body. You don't need to tell me how to reset the TPS, I wrote part of the VDSTS thread. and I've been servicing 5AM machines since 2006.

 

[canuck1969]

I got the software to open by reinstalling the driver software for the hardware key. Went into Device Manager in Windows, found the correct USB device and reinstalled driver. I tested it on my bike and reminded myself how everything works.

And, TPS CAN be reset in the IAW5AM computer, but it's done automatically by the software. But, it's NOT done by touching the throttle stops. The TPS reset is done if, after balancing throttles, the closed throttle reading is anything other than 4.7mV. If that's the case, you tell the computer to reset TPS and basically it tells the computer that the "NEW" setting IS 4.4mV. Essentially tells the computer *where* zero throttle is, and it references from there.

Anyhow, now I should be able to get my buddy's bike reset and ready to enjoy.

Look at this thread. You will find a link on how to adjust the sync (among other things). Very straight forward, as long as you don't turn the wrong thing............

https://www.guzzitech.com/forum/topic?f=221&t=10815

 

[John in PA]

You'd have to back off both throttle stops to get RPM's to drop and maintain balance at idle, or else I'm missing something.(??) Plus, I think the computer resets idle speed with the TPS reset, doesn't it?

Just been while since I monkeyed with this, and want top be sure I remembered correctly.

Since you mentioned backing off the screws here I thought I'd remind you not to do that to save the expense of a throttle body. You don't need to tell me how to reset the TPS, I wrote part of the VDSTS thread. and I've been servicing 5AM machines since 2006.

My "screw comment" was in reference to Todd's comment to only adjust one side, not cause i wanted to do it. I guess idle balance is set at the factory, as it wasn't far enough off to mess with anyway, and I do understand the impact of messing with those stop screws, having experimented with them on an early 2007 Norge (if you put them back where they were, no harm done, but a BAD idea to fiddle with them, I agree. I did that before I understood how the new system worked, and after working with p8's and 15M's for a few years)

No offense meant. I guess I read your comment too literally. Thanks for chiming in!

Where's the VDSTS thread? I'd like its link for future reference.

 

[John in PA]

Good stuff, Canuck! Thanks for the links!

 

[WayneOrwig]

Are you talking about the idle stop screws, or the air bleed screws?

BTW, John Z., the dashboard on the Stelvio (and the other CARC bikes) uses a digital tachometer with an analog hand. Very accurate actually.

 

[john zibell]

Wayne,

Yes they are pretty good, but with the analog hand open to interpretation and angle of viewing. When I'm working on a bike I prefer the digital readout from Centurion. Even that isn't a steady number as the speed at idle still varies.

 

[John in PA]

I was talking about the idle stop screws, I know not to mess with them (though I did years ago on a red Norge that I have that is a "shipping-container twin" to Bill Hagan's! Fortunately got it back to factory set-up by trial and error)

I actually forgot about the air bleed screws for balancing at idle till re-reading the tune-up instructions (when all else fails...)

Anyhow, I'll go out and re-do the balance and reset TPS on my friend's new bike now that I've got the software working again. I have no idea why the laptop lost it's connection with the hardware key driver for the VDSTS, but at least I figured out how to restore it. That was my primary problem--the bloody software program wouldn't open at all!

 

[AlanNZ]

Look at this thread. You will find a link on how to adjust the sync (among other things). Very straight forward, as long as you don't turn the wrong thing............

https://www.guzzitech.com/forum/topic?f=221&t=10815

Can someone explain why you would need to replace the TB if you adjust the stop screw. I assume it is a mechanical stop so if you move it from its current setting you should be able to reset it to the same setting again? Just curious.
Alan NZ

 

[canuck1969]

If you can set it to the exact same point then yes, it is not a problem. If you don't there is a crude procedure on here somewhere to get it back to the approximate position. They leave the TB factory preset at a specific throttle position based on air flow. The TPS needs to know that fixed position in order to sync the right side TB (4.6 to 4.8). If you move it, you will never get the TB's in sync since the TPS just assumes 4.6 to 4.8. But you are correct, if you put it back you will be fine. That being said, I still wouldn't want to take the chance.

 

[john zibell]

Alan, The hard part is to get it to precisely the same position. Therefor best not to touch it.

 

[AlanNZ]

If you can set it to the exact same point then yes, it is not a problem. If you don't there is a crude procedure on here somewhere to get it back to the approximate position. They leave the TB factory preset at a specific throttle position based on air flow. The TPS needs to know that fixed position in order to sync the right side TB (4.6 to 4.8). If you move it, you will never get the TB's in sync since the TPS just assumes 4.6 to 4.8. But you are correct, if you put it back you will be fine. That being said, I still wouldn't want to take the chance.

If it's that critical, and there is the potential to accidentally adjust, you would think the factory would make it more idiot proof eg cut the head off the screw or a permanent locking device.
Alan NZ

 

[john zibell]

It takes time to idiot proof the throttle stop. Time equals money so it isn't done. At least paint is put on the end of the screw to deter tampering.

 

[WayneOrwig]

Can someone explain why you would need to replace the TB if you adjust the stop screw. I assume it is a mechanical stop so if you move it from its current setting you should be able to reset it to the same setting again? Just curious.

On the CARC bike:
The idle butterfly stop set screw is set at the factory on a flow bench. That gives the proper amount of air flow in the TB. You should be able to correct any slight idle imbalance, with the air bypass screw.
Keep in mind that these bikes ALSO have the idle air stepper motor. So if you tweak the idle stop screw, the stepper motor may/will run, and try to correct for the change that you made. You can get into a situation where you do one thing, and the ECU tries to do something else. So it is best not to touch them.
The factory implies that if they have been touched, you throw them away and have to install new throttle bodies. Obviously that is overkill, but it hints at how important it is that they not be screwed with.