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VDST with 02 Sensor


Desdinova

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Hi Folks,

Well after several months of just looking at the Lemans, we had a nice day so I thought I would attempt to get it running and begin tuning the bike.

 

Quick History:

1. Some time back (2005) my bike was tuned and dyno'd but there were some quirks that I was never able to flush out.

2. Earlier this year, the bike's tuning deteriorated to point where it wouldn't run at all.

3. I decided to do the normal TPS, TB-adjust, Valve-Adjust and during that process....

4. ....was when I determined the bike had been previously setup with the Throttle Advance cable not completely disconnected.

 

This now meant everything was off. The PCIII Mapping was off, the idle trim was off, everything. Everything was compensating for something else being off because the throttle bodies never actually reached their closed position, hence the TPS was never set correctly.

 

Ok.. so here I am with two questions.

 

1. Is there a way to read the CURRENT trim setting with the VDST software. I thought there was, but mine seems to come up ZERO until I adjust and save, but I think it resets back to ZERO once I shut off the bike.

 

2. For those using VDST software, what are you using for an O2 Sensor. I hate to spend $300 for a one time use item. In fact, if someone has one I could borrow... that already fits the fitting on the pipes, I'd be forever indebted. I would just need it long enough to set the trim properly with a Zero's PCIII Map, so I could then take the bike and get it Dyno'd knowing the PCIII wouldn't be "compensating" for the trim being incorrect. I doubt the place I'm gonna take the bike has access to the ECU... although I guess I could bring my laptop with me and let them use it.

 

3. For those with an O2 Sensor, what have you set the air/fuel to read at idle. I have seen 13:1 but wanted to hear from people who have actually measured it.

 

Anyway, I'm open for idea's. I miss riding my LeMans. It runs, but it's very sluggish cause the trim is likely way off. I know what the bike can do, I just want to get it back to that point now that I know it's all set up properly from the mechanical side.

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3. For those with an O2 Sensor, what have you set the air/fuel to read at idle. I have seen 13:1 but wanted to hear from people who have actually measured it.

13:1 or slightly leaner should be sane, although I tend to listen to the engine and also try how it reacts to a quick roll of the throttle.

 

I've seen tables for "correlation between CO and O2". I'm not sure that is an exact science but if it is, 13.2:1 corresponds to a CO of 3.5.

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4. ....was when I determined the bike had been previously setup with the Throttle Advance cable not completely disconnected.

 

This now meant everything was off. The PCIII Mapping was off, the idle trim was off, everything. Everything was compensating for something else being off because the throttle bodies never actually reached their closed position, hence the TPS was never set correctly.

 

So now that you've properly adjusted the TBs, etc. and the map is off... dump the map!

 

Yeah, I know: it's hard to dump a custom map you paid good money for, improperly done or not, but which is more important: chasing some chimera of a means to adjust the f!cked up map, or having a Guzzi that runs right?

 

Try substituting a generic V11 PCIII map [tons of'em over at Guzzitech, iirc] for a bike w/ the same farkles as yours, & see if that improves your situation. If not, you can always revert to the messed up custom map...

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Skeeve, as I mentioned... the map is dumped (although I spelled zero'd wrong). I need to set the idle trim on the ECU before I put a new map or do anything. The bike runs, but just barely.. it's probably too rich... Normally this is done at the factory and it likely never changes, but someone monkey'd with it so I need to set it again. I tried to do it by ear, but I can't seem to get the VDST to save the setting properly, which is part of the issue, the other is I really need an -02 wand to do it right. Can't even attempt mapping until this is done and need an 02 wand to do it.

 

I may try again by ear today, just to get it back on the road.

 

-mkb

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Got it running ok today. Did a little experimenting to get the trim at least close which I did.

 

Applied a MAP from a similar setup I download from Guzzi Tech.

 

I really need to get this thing to a dyno, but alas... the one that should have been parked in my driveway hasn't appeared and there isn't a reliable one that I know of within reasonable or even unreasonable travel distance... :(

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