detonation

[dlaing]

I respectfully disagree.

 

If the pinging is caused by too lean mixture (which is the case with a stock setting to begin with and then, after some modifications to intake/exhaust it becomes really excessive) then richening is NOT the short term solution BUT the only proper one and no carbon build-up is expected.

 

Once again: first make sure the mixture is close to proper one and then worry about valves, TPS, idle, balance etc.

 

Unless Im missing something. If that is the case please tell me what.

What you said is true.

Certainly if you take a good running bike, add a free flowing muffler and it starts to pink, adding fuel is the proper solution.

And in many other cases adding fuel is a good enough solution

But I am not sure why you disagree.

If you simply take a PCIII to a stock Guzzi tuned by the shop to compensate for emission legislation, add some overly rich map that you downloaded, you could be running rich enough to cause carbon build-up and eventually get a pinging problem.

But heck, I could be missing something too, and carbon buildup may never cause pinging on our bikes, even running 10:1 fuel ratios?????????

But I doubt that it is a non-possibility, and I'll bet many of our bikes with Power Commanders and downloaded maps, have more than ideal carbon buildup, so much so that if we put the bike completely back to stock we would have pinging issues.

Again, I could be wrong...

[luhbo]

I agree that you need to richen it up a good bit if you modify the intake or exhaust. If you open either end up & dont give it more fuel it will ping.

 

And I do not agree and I say: don't invest in a PC (ceterum censeo ..., you know )

 

I never noticed any difference in fueling requirements unless I run it at WOT and above 6000 min-1. Below that there is no remarkable flow restriction caused by cans or airbox. Normaly the bike runs at revs below 5000 even better with standard equipement. Running better means better air flow and so normally a tendency to leaner mixtures.

 

One question to the one who said you sould avoid bio-gas. Why should alcohol increase the tendency to ping? I always thought it had a much higher octane rating as mineral fuel.

 

Has someone ever checked the position of the phase sensor as a possible cause for pinging? There are a lot of V11 that never ping, some do it only slightly from time to time, and some seem to ping always regardless what qualitiy of fuel they get. To me this looks more as problem of tolerances. If not just tolerances in reception, then tolerances of assemblage --> position of phase sensor.

 

Hubert

[Guzzi2Go]

What are you suggesting luhbo? Is it that the phonic wheel may be screwed in at an "advanced" angle to the crank? From what I see this one is "nailed" to the cam and can be inserted in one way only.

 

I also do not see what adjustment options are available for the phase sensor itself.

 

The only options obvious to me to address this issue are electrical (TPS, ECU, PC, ...)

 

BTW, mine pings at low rpms @WOT, never at >5000 rpm and it is all stock, even when running on 100 octane fuel. I tend to interpret this as inability to inject correct amount of fuel at these speeds, rather then inability to retard the spark.

 

But then again, what do I know....

[luhbo]

....I tend to interpret this as inability to inject correct amount of fuel at these speeds, rather then inability to retard the spark.

 

But then again, what do I know....

 

Yes, who knows what. The manual at least says the phasesensor has to be adjusted when it's getting mounted, some even say it should be cleaned from time to time. The manual even shows a picture for that.

 

Don't ask me how it works with this sensor, my KR doesn't ping, regardless what colour the fuel has that I get for it. So I had no need to check this part of the signal chain so far.

 

Hubert

[Guzzi2Go]

Well, what can be adjusted is the air gap between sensor and phonic wheel. The air gap will affect amplitude and offset of the signal, but not its phase, so I would exclude that as a cause for pinging.

 

BTW, how does TÜV react on your My15M (ASU)? Has the subject ever come up?

[luhbo]

Well, what can be adjusted is the air gap between sensor and phonic wheel. The air gap will affect amplitude and offset of the signal, but not its phase...

 

That's probably right as long as it sits perfectly (within allowed tolerances) perpendicular over the axis of the wheel. And also the software must be stable enough to work properly with signals of different or maybe even variing strength.

 

It's a bit of guessing, sure, but nobody so far ever mentioned this part. I know from cars that it's very often the cause of problems and break downs.

 

TUV never was a problem. "Wer viel fraecht, ged viel irr" as some say. And not only in a forum.

 

Hubert

[Cliff]

What's TUV?

[raz]

It's TÜW. German homologation. I'm puzzled I can't find it on any Wikipedia, not even the German one. In the context above I guess it's like MOT, annual test/approval for vehicles.

 

Also, aftermarket exhausts, lights, turning indicators and such things can be "TÜW approved" and then you can just mount it and it will be OK without hassle with authorities. That goes for me too in Sweden, because of the European Union.

[Guzzi2Go]

TÜV is MOT. In order to pass the "exam", your bike has to be within manufacturer specs in almost all aspects. Noise, pollution, speed, power, wheels, tires, springs/shocks, etc. So free fiddling with mufflers, ECUs, gear ratios, tires, etc. is basically illegal, and if you really insist on it you should put your bike through homologation on your own expense, or find the parts that are homologated for your bike. In addition, if you did any modifications to your bike you have to carry documentation of it with you all the time.

 

What I asked luhbo is if he had problems doing the pollution test, since changing the fuel map will obviously change exhaust gases characteristics. TÜV would usually notice that and complain.

[Skeeve]

The reputation of TUV being such a big monster is the stories of their insisting on OEM tires for a motorcycle, etc. [ie, inane bureaucratic pigheadedness] instead of realizing that a 120x70ZR17 is a tire, is a tire, is a tire and rightfully up to the rider's choice (& budget) to determine.

 

Think of it as MOT on steriods. The kind of steroids that cause brain tumours and make the user go insane.

[raz]

That shit has come to Sweden too, it's an EU thing. The tires are usually not bound to exact make and model, but exact dimension and speed rating. Or rather, whatever is literally written out in the Certificate of Conformity, you can not change. So if the papers state a make and model tyre, you are bound to it. If the papers state a 280 km/h tyre for a street car, you must use such tires even though you can't legally go faster than 120 km/h on Swedish roads.

 

A good reason to ride an 11 year old bike Actually they don't even test my exhaust gases at all.

[Guzzi2Go]

We drifted away...

 

So some bikes ping, some not, although they all seem to be the same. Two options have been discussed so far:

- we are running (too) lean

- our timing is screwed (valves and/or ignition)

 

What seems to be more likely?

 

I am familiar enough with microcontrollers, digital electronic, software and signal conditioning not to buy the argument that distance of the crank sensor to the phonic wheel would contribute to this particular problem, although timing in general could be the issue. Would it be possible that entire cam is "misdialled" on machines that ping? This would cause valves to work differently, but also put phonic wheel in an "unfavourable position". The manual also describes procedure how to align the cam with the crankshaft. Would that be worthwile checking? Has anyone?

[raz]

The manual also describes procedure how to align the cam with the crankshaft. Would that be worthwile checking? Has anyone?

I never understood that "degree wheel" page in the WHB as there is nothing to align (except the marks must point right). All parts are keyed. I think the only outcome of that procedure is that you verify that the TDC marks on the flywheel are punched where they should be, and that you didn't put the cam 180 degrees out of phase. But you don't need the degree wheel for that anyway!? Or do I miss something?

[Guzzi2Go]

I never understood that "degree wheel" page in the WHB ...

Same thing here. I could imagine that cam offset to crank position may be tolerated in a +/- few degrees range for as long as the valves do not meet pistons. Ignition time point is probably more sensitive than that.

 

But then, I know too little on engines to make such a claim.

[Tom M]

We drifted away...

 

So some bikes ping, some not, although they all seem to be the same. Two options have been discussed so far:

- we are running (too) lean

- our timing is screwed (valves and/or ignition)

 

What seems to be more likely?

 

There's at least one other possible cause for some bikes pinging and some not that isn't related to fuel quality or what you mentioned above; squish clearance. It was discussed here, and there's a great web page that shows how to set it on an air cooled Harley motor here.