Cali EV detonation

[guido]

My Calidfornia EV is detonating at high speed. It has taken a while to convince myself that this is actually what happens, but it is prominent on hot days, up hill and two up, above 140km/h. It seems to start after sustained speed of 5 to 10 minutes. you hear a mechanical noise, not like the normal ping, but something more like a hammering sound. After it starts, more power just give more noise, not much more speed.

We can get only 93 and 95 perol. Strangely, 93 or 95, it does not seem to make a difference. We are 1600m above sea level, and it is rather hot about 30 Celcius.

I am after the easiest changes first, like spark plugs, ignition etc, but I am not sure what can be adjusted on the EV.

Any ideas?

[Guest Mattress]

Can we petition Moto Guzzi to give us some $$ to study this problem. It is a fairly regular complaint that pops up here. Pre-ignition itself in spark ignition engines is well understood, but why does it pop up seemingly randomly on V11 engines?

 

Yours seems temp related. Willing to be a guiena pig for the study and replace your temperature sensor holder with a brass unit? Maybe it is not reading correctly and throwing off the ecu calibration.

[motoguzznix]

Guido

 

First an foremost the valve clearence cold should be adjusted to 0,20 inlet and 0,25 exhaust.

Next step is adjustment of the throttle potentiometer at 150 mV, and synchronisation of the throttle bodys. You will find some advice for this when searching in this forum.

Next step adjust the CO to approx. 3-3.5 %. This is on the early P8 via a sealed poti beside the large ECU plug. On the later 1.5 ECU it has to be done by your dealer via the axone diagnose tool or something similar.

This should help a lot.

[Guest ratchethack]

Guido, this has been an on-going topic of discussion and I've been most interested in gathering intelligence on this myself.

 

A long list of factors contribute to ping (spark plugs ain't one of 'em). Several (myself included) have focused on the ping problem from the perspective of two fundamental factors -- fuel quality and combustion chamber shape. Can't do a single reasonable thing about the former, but the latter is of great interest lately, and I'm hopeful.

 

Wot I'm after is I suspect much the same as y'erself and others -- a well informed approach to doing a comprehensive top-end refurb at some point downstream. In my own case, I'm hoping to incorporate the right kinds of cylinder head modifications -- NOT for the purpose of chasing curves on the dyno -- but for fuel burn optimization with our less-than-optimal ethanol-contaminated fuel here in sunny California, which I suspect may be as bad or worse than yours, the quality of which I have ZERO expectations for getting any better at any point in the future.

 

If you don't mind wading through some truly amazing acrimony and bile-spewing (WARNING: Why some of the emotion-laden dreck und sturm and apparent defensive behavior that this topic conjured up would ever be necessary is far beyond my comprehension?? ) you might be interested in the thread here, where IMHO much of what is relevant, known, and likewise unknown is discussed, along with some illustrations and direct measurements of the combustion chamber that I found of value. For whatever reason, others evidently somehow found this "offensive". :

 

http://www.v11lemans.com/forums/index.php?...=8819&st=0#

 

I've been eagerly waiting ever since this thread 6 months ago for an update from our Austrian friend, Ernst (Motoguzznix) for an update on his progress. IMHO he seemed to be on the right track with a rational approach, direct experience, and a good grasp of the principles at work!

 

EDIT: I see Ernst has beat me to the punch with his reply above!

 

Wot news, if any, of your progress on squish band and cylinder head modification, Ernst??

[Guest Mattress]

I checked out that thread. Lots of talk about the combustion chamber design, and speculation about squish. All that is fine and dandy, but it doesn't address other factors involved in pre-detonation or "ping" such as the influence of ignition timing and flame front travel.

 

I suppose you can monkey around with creating a custom squish band, but if a more efficient burn and less likely pinging is your goal, why not just go for dual plugging?

 

TLM quoted me about 800 euro with 1-2 week turn around, includes ECU reprogramming to adjust advance. If you have MyECU or Tuneboy that can adjust advance, you'd save about 300 euro.

[Guest ratchethack]

I checked out that thread. Lots of talk about the combustion chamber design, and speculation about squish. All that is fine and dandy, but it doesn't address other factors involved in pre-detonation or "ping" such as the influence of ignition timing and flame front travel.

 

I suppose you can monkey around with creating a custom squish band, but if a more efficient burn and less likely pinging is your goal, why not just go for dual plugging?

 

TLM quoted me about 800 euro with 1-2 week turn around, includes ECU reprogramming to adjust advance. If you have MyECU or Tuneboy that can adjust advance, you'd save about 300 euro.

Mattress, o' course there are many ways to look at skinning this cat, depending on wot y'er trying to achieve, but I'm about as certain as I can be that we aren't all trying to achieve the same thing!

 

One might reasonably ask up front how much time and money would one reasonably expect to throw at it relative to the results one expects to achieve?? Since we seem to be more or less permanently limited by bad gas (at least where I live), I'm looking at all reasonable options, with an eye toward cost and benefit, and real-world practical road travel. Certainly dual plugging could be one approach, but 800 Euro seems a bit much relative to the cost/benefit of mild head work. In my own case, knowing that at some point (and it won't be all that long now!) I'll have the heads off for refurb., I became interested in looking at a less "invasive", simpler, easier, and less expen$ive approach that might make more sense from a cost/benefit perspective.

 

Sure you can back off timing to address ping. If that's all there were to it, it'd be the cost/benefit King. But IMHO that's trading one problem for others without eliminating the root cause. Backing off timing has undesirable trade-off effects, such as poor mileage, for example. Flame-front travel? It's a function of many things, including most prominently, cylinder head shape and squish band characteristics, which is exactly wot we've been talking about.

 

Sure the woods 'r full o' dyno-chart-peak chasing approaches. This is the business of Mich Rich and many many others. Not to take a single thing away from Mike Rich or anyone doing power peak tuning for track or world land speed record chasing! I'm not interested in the slightest, but that's just me. On the road, I can't be limited to race fuel, and I don't EVER ride around at WOT, which is mostly wot I expect Mike tunes for on the dyno. IMHO, most of the "common" go-faster modification approaches that look so impressive on the dyno charts are going in the wrong direction for tractability on the road and long-term durability, which is wot I'm interested in. IMHO, particularly when you've got bad fuel to deal with, most of the hot rod mods are NOT helpful -- in fact, they're extremely UNHELPFUL.

 

The cylinder head measurements of the stock heads that Ernst came up with, along with his drawings that illustrate (at least to me) a poor combustion chamber shape without any squish band at all, were an indication to me that some mild head work along the lines of what Ernst has been doing JUST MIGHT go a long way toward helping more efficient burning of our crap gas. I eagerly await more information. Ideally, someone will have taken this approach and be able to provide credible, positive results.

 

I'm like Guido -- I'm after the easiest changes first, and I'll bet others (like Ernst) have already been down the same path -- just thinking that many of us with similar goals might benefit from that kinda experience, and a more $imple, $ensible $olution to ping for the road with bad fuel -- IF IT EXISTS!!

 

BAA, TJM & YMMV

[Guest Mattress]

Mattress, o' course there are many ways to look at skinning this cat, depending on wot y'er trying to achieve, but I'm about as certain as I can be that we aren't all trying to achieve the same thing!

 

One might reasonably ask up front how much time and money would one reasonably expect to throw at it relative to the results one expects?? Since we seem to be more or less permanently limited by bad gas (at least where I live), I'm looking at all reasonable options, with an eye toward cost and benefit, and real-world practical road travel. Certainly dual plugging could be one approach, but 800 Euro seems a bit much relative to the cost of mild head work. In my own case, knowing that at some point (and it won't be all that long now!) I'll have the heads off for refurb., I became interested in looking at a less "invasive", simpler, easier, and less expen$ive approach that might make more sense from a cost/benefit perspective relative to the results I expect to achieve.

 

Sure you can back off timing to address ping, but IMHO that's treating the symptom rather than the cause, and backing off timing has undesirable trade-off effects, such as poor mileage, for example. Flame-front travel? It's a function of many things, including most prominently, cylinder head shape and squish band characteristics, which is exactly wot we've been talking about.

 

Sure the woods 'r full of dyno-peak chasing approaches. This is the business of Mich Rich and many many others. Not to take a single thing away from Mike Rich or anyone doing power peak tuning for track or world land speed record chasing! I'm not interested in the slightest, but that's just me. I can't be limited to race fuel, and I don't EVER ride around at WOT, which is mostly wot I expect Mike tunes for on the dyno. IMHO, most of the "common" go-faster modification approaches that look so impressive on the dyno charts are going in the wrong direction for tractability on the road and long-term durability, which is wot I'm interested in. IMHO when you've got bad fuel to deal with, most of the hot rod mods are NOT helpful -- in fact, they're extremely UNHELPFUL.

 

Now the cylinder head measurements of the stock heads that Ernst came up with, along with his drawings that illustrate (at least to me) a poor combustion chamber shape without any squish band at all, were an indication to me that some mild head work along the lines of what Ernst has been doing JUST MIGHT go a long way toward helping more efficient burning of our crap gas. I eagerly await more information.

 

I'm like Guido -- I'm after the easiest changes first, and I'll bet others (like Ernst) have already been down the same path -- just thinking that many of us with similar goals might benefit from that kinda experience, and a more $imple, $ensible $olution to ping for the road with bad fuel -- IF IT EXISTS!!

 

BAA, TJM & YMMV

 

 

Fair 'nuff. Itll be interesting to see what you do & achieve.

 

My edumacted guess is that guzzi had to compromise on the design to meet the emissions regs that came into effect in the 90s. I'm sure the squish band helps combustion. But squish band is also crevice volume and that means unburned hydrocarbons and increased emissions, much like when I quaff down one of Chicago's hot dogs with extra chilli.

 

Current engine designs are reducing crevice volume in all sorts of combustion chamber designs. Mostly through raising the top ring.

 

Maybe when guzzi went to dual plug on the new Breva engines it allowed them to put the squish band back in the chamber.

[Cliff]

I am after the easiest changes first, like spark plugs, ignition etc, but I am not sure what can be adjusted on the EV.

Any ideas?

 

The first thing anyone should do here is to make sure the bike is setup properly. The main things here are the throttle balance and TPS. The TPS setup affects both the mixture and spark advance so make sure it is done right.

 

If it still pings after correct setup, try the TPS tweak. Adjust it to increase the voltage a smalll amount, say 10-20mV. The will increase the mixture and also retard the ignition. It may also increase your fuel consumption.

[Guest ratchethack]

. . . squish band is also crevice volume and that means unburned hydrocarbons and increased emissions, much like when I quaff down one of Chicago's hot dogs with extra chilli.

Erf, kaff! As I recall, this points out one o' the great traditional advantages o' seeing the Cubs do wot the Cubs do best at Wrigley Field (I won't say wot ) -- Wrigley has no roof -- and that's a GOOD THING!

[Guest Mattress]

Erf, kaff! As I recall, this points out one o' the great traditional advantages o' seeing the Cubs do wot the Cubs do best at Wrigley Field (I won't say wot ) -- Wrigley has no roof -- and that's a GOOD THING!

 

True. But I'm a Tiger's fan so I only go to Comisky. Now called U.S. Cellular Field. The Cubs draw all the young and beautiful and it is more like one big College Party, though to be fair. Only I don't seem to register on the radar screens of young lassies anymore - I've slipped over into the stealth age.

 

But, did my logic about the disappearing - reappearing squish band make sense to you? I think when guzzi was designing the V11 engine they tried to open up the squish band for emissions. Dual Spark provides two origins for the flame front, providing more complete combustion for a hemi-head and it's required domed piston. So bink, now we can bring back the squish band and it's crevice volume.

 

What about the timing system? Has anyone found the pickup sensor out of wack or position?

[Guest ratchethack]

. . .did my logic about the disappearing - reappearing squish band make sense to you? I think when guzzi was designing the V11 engine they tried to open up the squish band for emissions. Dual Spark provides two origins for the flame front, providing more complete combustion for a hemi-head and it's required domed piston. So bink, now we can bring back the squish band and it's crevice volume.

Mmmmmmm....... Well, yes. Your "crevice volume" thoughts are well taken. Seems to me the Pro's who build these engines on a fairly regular basis have been drawing on a knowledge base that spans many decades. For the most part, the principles at work 40 years ago still apply, because not much has changed over the years. I've begun to suspect that wot we wound up with for cylinder head shape in the stock V-11 has "built-in" compromises, that at various stages of development became matters of "expediency" at the Guzzi works, and allowed them to get thru requiements for production without tooling changes when using much higher quality fuel than many of us have access to today.

 

Now that most of us have far worse fuel than they did decades ago, we've inherited some problems that new engine designs don't have, because they were built for "modern" fuels as dictated by the Eco-Nazi's.

Dual Spark provides two origins for the flame front, providing more complete combustion for a hemi-head and it's required domed piston. So bink, now we can bring back the squish band and it's crevice volume.

Makes sense to me, but then, I'm no engine designer. I say if at all possible, by all means leave us discover wot the Pro's know, and if possible, approach top-end re-work based on wot they've discovered works far better with our crap fuel. Dual spark may be an option -- and a good one at that, but I'll bet there are a few less "strenuous" alternatives for the road that make perfect sense. Many have suggested getting back to a 1 mm or .040" squish band is a solid approach. This sounds reasonable to me, FWIW.

[Guest Mattress]

Mmmmmmm....... Well, yes. Your "crevice volume" thoughts are well taken. Seems to me the Pro's who build these engines on a fairly regular basis have been drawing on a knowledge base that spans many decades. For the most part, the principles at work 40 years ago still apply, because not much has changed over the years. I've begun to suspect that wot we wound up with for cylinder head shape in the stock V-11 has "built-in" compromises, that at various stages of development became matters of "expediency" at the Guzzi works, and allowed them to get thru requiements for production without tooling changes when using much higher quality fuel than many of us have access to today.

 

Now that most of us have far worse fuel than they did decades ago, we've inherited some problems that new engine designs don't have, because they were built for "modern" fuels as dictated by the Eco-Nazi's.

 

Makes sense to me, but then, I'm no engine designer. I say if at all possible, leave us discover wot the Pro's know, and if possible, approach top-end re-work based on wot they've discovered works with our crap fuel. Dual spark may be an option -- and a good one at that, but I'll bet there are a few less "strenuous" alternatives for the road that make perfect sense. That's my take, FWIW.

Well hell dude I'm not either. My background is metallurgical engineering, staring down microscopes, staring at my shoes when girl engineers walk past. Castings these days are commodities. I got caught. I bet brillance or critical thinking skills would beget some comfort in life, it doesn't. You just end up with a nasty student loan bill.

[motoguzznix]

I've been eagerly waiting ever since this thread 6 months ago for an update from our Austrian friend, Ernst (Motoguzznix) for an update on his progress. IMHO he seemed to be on the right track with a rational approach, direct experience, and a good grasp of the principles at work!

 

EDIT: I see Ernst has beat me to the punch with his reply above!

 

Wot news, if any, of your progress on squish band and cylinder head modification, Ernst??

Ratchet

I am still looking forward in this direction, but could not manage to pull the heads off my V11. In the meantime I detected an other area in the V11 heads to be modified, see here This needs some investigation and I am working on it.

Eventually I wanna fix all the issues concerning the heads at the same time not knowing when this will be the case.

 

I suppose you can monkey around with creating a custom squish band, but if a more efficient burn and less likely pinging is your goal, why not just go for dual plugging?

 

TLM quoted me about 800 euro with 1-2 week turn around, includes ECU reprogramming to adjust advance. If you have MyECU or Tuneboy that can adjust advance, you'd save about 300 euro.

Matt

 

I suppose guido is not looking for an expansive engine conversion, just wants to fix the pinging issue.

Cliff has almost the same ideas like me and this should be the first steps to cure the problem.

Concerning the heads, the Cali has a much better combustion chamber shape like the V11. The chamfer at the outer diameter of the chamber does not exist in these heads. To get an optimal sqush band, only the cylinder barrels have to be shortened to get the pistons completely on top of the bore. But I would only go that far and pull the heads when engine adjustment is not able to control the issue.

[Guest ratchethack]

Ratchet

I am still looking forward in this direction, but could not manage to pull the heads off my V11. In the meantime I detected an other area in the V11 heads to be modified, see here This needs some investigation and I am working on it.

Eventually I wanna fix all the issues concerning the heads at the same time not knowing when this will be the case.

Matt

Thanks for the update, Matt. I hadn't missed your porting analysis. Good work!

 

Have you considered swapping heads and cam? This takes me back a few years to my understanding back then that one of the primary drawbacks of the design of V-11 heads for the road is that the valves are larger than ideal for the kind of low and midrange torque I consider most desirable for the road. Before Todd Eagan swapped engines in his Jackal for one from a Sport, I'd considered swapping heads and cam with him. I reckon the small-valve, milder cam Jackal engine is better suited to the road for 99+% of riders, whether they understand this or not. Todd (being truly one o' those 1%'er's! ) was interested in doing this, but at that point in time, I had relatively low miles on my Sport heads and had no other reason to have the heads off, and I didn't have enough motivation for this kind of excursion without a need for heads off in the first place.

 

Since "bigger" and "more" is generally always considered "better" in the world of moto modification, I suspect it wouldn't be too difficult to find a Jackal rider somewhere interested in a swap when it's time for top-end refurb. To each his own, as they say? I'd be interested to know if you'd considered this y'erself.

[RacerX]

takes me back a few years to my understanding back then that one of the primary drawbacks of the design of V-11 heads for the road is that the valves are larger than ideal for the kind of low and midrange torque I consider most desirable for the road... I suspect it wouldn't be too difficult to find a Jackal rider somewhere interested in a swap when it's time for top-end refurb.

I've got a pair for anyone so interested... ready and willing.

I'd say that the Cal/EV heads/cam are pretty fantastic for riding anywhere besides the SouthWest USA. I spent over 90k miles on the stock Jackal motor (72 dyno-proven rwhp), and absolutely loved it. However, the V11 Sport motor with the Cal 5-speed trans and custom 2-1 exhaust, makes for a pretty impressive package for West Coast style "sport" riding and wide-open, uhmmm, spaces.