3000rpm hiccup

[Lucky Phil]

I just had a thought triggered by an issue on the V85TT's caused by what appears to be EMI from the ignition coil affecting the crank angle sensor pickup cable. Causes erratic idle apparently and the Guzzi TSB fix is to re route the wire away from the HT lead I'm led to believe.

I was wondering if anybody with the 3000 rpm hiccup as a chronic issue on their bike might like to see if the crank angle sensor pickup cable or connector is anywhere near the HT lead to the sparkplug. Looking at old images of the wiring on my bike before the engine swap the connector and cable were right next to and touching the r/h coil HT lead. Might be worth looking at and if it's close reroute the cable to keep it as far away as possible and see if there is an effect. ( the std cable has lots of length from memory) 

 

Ciao

[footgoose]

Brilliant. I'm useless with electrics yet this makes sense. I don't have the hiccup but I'll have a look anyway.

[docc]

9 minutes ago, footgoose said:

Brilliant. I'm useless with electrics yet this makes sense. I don't have the hiccup but I'll have a look anyway.

    

[Lucky Phil]

Just now, docc said:

Might need to hold off on the "brilliant" it's just a maybe and possibly and be good if it was scenario.

Ciao

[docc]

The proximity certainly checks out!

[docc]

This also causes me to wonder how much HT coil leads degrade over time and "might-could" make the EMI more pronounced (less contained) . . .

(Still my original HT leads/ "spark plug wires" . . .)

[Lucky Phil]

14 minutes ago, docc said:

This also causes me to wonder how much HT coil leads degrade over time and "might-could" make the EMI more pronounced (less contained) . . .

(Still my original HT leads/ "spark plug wires" . . .)

Does your hiccup docc? I don't think you can insulate EMI unless you use specific shielding. It needs more than just plug wire insulation I believe.

Ciao

[docc]

On 9/14/2021 at 8:53 PM, Lucky Phil said:

Does your hiccup docc?

Ciao

It's a clapped-out old V11 Sport, eh? So, hell-yeah. Fine ripping up and down through the R's or at 4k+ rpm, but get stuck behind draggy traffic at steady throttle (especially in hot ambient temps) and she bitches-and-pisses-and-moans. I chased the "Nasty Hiccup" for ten years (2007-2017) and found myriad causes. Every remedy made it better. For a time. 

A couple weeks ago, we ran across some fine fellow with a low mile (9100) '97 Sport-i who asked about this behavior. I told him, "Of course. Yes. It's The Dragon"

So frustrating, I once said, "Riding the Sport at a slow, steady speed is like asking your Tango chick to waltz. She'll do it, but it's gonna piss her off."

I'm excited about this discovery! My Sport is a definite candidate to separate those wires and monitor for change.

[Lucky Phil]

2 minutes ago, docc said:

It's a clapped-out old V11 Sport, eh? So, hell-yeah. Fine ripping up and down through the R's or at 4k+ rpm, but get stuck behind draggy traffic at steady throttle (especially in hot ambient temps) and she bitches-and-pisses-and-moans. I chased the "Nasty Hiccup" for ten years (2007-2017) and found myriad causes. Every remedy made it better. For a time. 

A couple weeks ago, we ran across some fine fellow with a low mile (9100) '97 Sport-i who asked about this behavior. I told him, "Of course. Yes. It's The Dragon"

So frustrating, I once said, "Riding the Sport at a slow, steady speed is like asking your Tango chick to waltz. She'll do it, but it's gonna piss her off."

I'm excited about this discovery! My Sport is a definite candidate to separate those wires and monitor for change.

Excellent, will be interesting to know if it has a positive effect. Chances are it won't but its a low effort zero cost situation. What could possibly go wrong:)

Ciao

[docc]

What is the source of the "issue on the 850TT"  you referenced in the original post? Is this referring to the new V85TT?

[Lucky Phil]

1 minute ago, docc said:

What is the source of the "issue on the 850TT"  you referenced in the original post? Is this referring to the new V85TT?

Yep the new bike V85TT.

Ciao

[Chuck]

That was one of the things I tried when sorting the Centauro back in the day.

It didn't help.

[p6x]

When I was in battle tanks, all the cabling was shielded and tested in a Faraday cage. I am talking about the systems to automatically acquire targets and follow while the tank is moving. To isolate from electrical motors interference.

There should be something commercially available for the spark plug cable? no?

 

[p6x]

I also wanted to report that since the temperatures have considerably cooled down here, in Houston, the V11 does not cough as much as before.

I have not done any substantial mileage lately, so it needs confirmation. But I use the bike to run errands, and I have not had any sign so far.

[Lucky Phil]

10 hours ago, Chuck said:

That was one of the things I tried when sorting the Centauro back in the day.

It didn't help.

Did the Centy hiccup as well Chuck?

Ciao