'04 Cafe Sport Dyno Run

[Ryland3210]

I just had my bike dynoed by John Tavolacci at Cliff's. The chart is below. The mapping is stock and the bike has about 5,000 miles on it. It has Staintune mufflers without the baffles, and standard filter with no airbox cover, clamp supplied courtesy of Ratchethack. Evidently the stock mapping was rich enough that the usual leaning effect by improving breathing resulted in near optimum AFR for my purposes. The compensation for the ambient conditions was per the SAE, so actual output was 1% higher than the chart indicates. I'm delighted to be so lucky, and love the sound and performance of the mod's. John did a great job of comparing my bike to several other Guzzi's he had done in the past with various options, and checking the AFR in all of the major operating conditions for me.

 

[dlaing]

That AFR looks better than what most I have seen look like AFTER mapping!

EDIT Sorry, I did not write the above correctly. The resulting AFR is almost always better after mapping. I was just impressed with how flat that curve was.

Flat looks good, is not always good. Many are not that flat after mapping, but power is maximized.

[GuzziMoto]

I like how steady the A/F is, but in my experience 14.7:1 is optimum for low emissions(when coupled with a cat) and somewhere between 12 and 13 to 1 is where max power lives. And for reasons that are debatable air cooled motors like Guzzi's and older Ducati's make max power with air fuel ratios a bit richer then modern liquid cooled motors do(and seem to be happier as well).

[tmcafe]

I just had my bike dynoed by John Tavolacci at Cliff's. The chart is below. The mapping is stock and the bike has about 5,000 miles on it. It has Staintune mufflers without the baffles, and standard filter with no airbox cover, clamp supplied courtesy of Ratchethack. Evidently the stock mapping was rich enough that the usual leaning effect by improving breathing resulted in near optimum AFR for my purposes. The compensation for the ambient conditions was per the SAE, so actual output was 1% higher than the chart indicates. I'm delighted to be so lucky, and love the sound and performance of the mod's. John did a great job of comparing my bike to several other Guzzi's he had done in the past with various options, and checking the AFR in all of the major operating conditions for me.

 

Nice! Looks "flatter" (no pun intended) than I thought and what I remember seeing posted online. When I get a chance I'll check mine--after the TPS and idel rpm. Cold outside and no heating in the garage.

[Pierre]

I like how steady the A/F is, but in my experience 14.7:1 is optimum for low emissions(when coupled with a cat) and somewhere between 12 and 13 to 1 is where max power lives. And for reasons that are debatable air cooled motors like Guzzi's and older Ducati's make max power with air fuel ratios a bit richer then modern liquid cooled motors do(and seem to be happier as well).

Nope, they make more power leaner - just like water cooled motors. Heat becomes an issue.

[RacerX]

John's dyno is more of a realistic dyno. I helped him get it going.

 

After spending several hundred hours on the dyno with Guzzis, as A/F increases = less power/more heat. Air-cooled motors are largely fuel-cooled. Tireless debate here, proving fruitless. No wonder John doesn't post here any more. Mapping is pretty lean on the bike/graph above.

 

I broke my word of posting here for this. Won't happen again.

[dlaing]

Nope, they make more power leaner - just like water cooled motors. Heat becomes an issue.

No, you are all wrong!

Sometimes they make maximum power at 13:1, sometimes richer and sometimes leaner.

[dlaing]

I just had my bike dynoed by John Tavolacci at Cliff's. The chart is below. The mapping is stock and the bike has about 5,000 miles on it. It has Staintune mufflers without the baffles, and standard filter with no airbox cover, clamp supplied courtesy of Ratchethack. Evidently the stock mapping was rich enough that the usual leaning effect by improving breathing resulted in near optimum AFR for my purposes. The compensation for the ambient conditions was per the SAE, so actual output was 1% higher than the chart indicates. I'm delighted to be so lucky, and love the sound and performance of the mod's. John did a great job of comparing my bike to several other Guzzi's he had done in the past with various options, and checking the AFR in all of the major operating conditions for me.

That is the flattest stock lambda curve that I have seen.

While a little lean compared to what most tune to to get maximum power, it is probably a good compromise for maximizing fuel efficiency.

Should you be concerned about heat?

Compare it the curves in the forum's dyno gallery

http://www.v11lemans.com/forums/index.php?showtopic=8556

Please consider adding your dyno there.

[guzzi jon]

My 02 Lemans ran perfect, but after opening up the airbox, I decided to pun on an older serial PCIII. I have mistral pipes, an FBF x-over and modded airbox. Before mapping, it made a healthy 77 bhp, after mapping (and this was at 2600 ft elevation), it made nearly 85 bhp, and was the strongest running guzzi I have ever ridden, it wheelied very easy (roper sloppage plate installed) and got better mileage as well. Louie knows the guzzi's well, and really dialed it in. It still shows a dip, but it was so strong, you never noticed anything but horsepower and torque

[Ryland3210]

Looks nice, as it should. It has the usual dip just over 4K. Makes more power (by 5) than a Norge 1200, as sad as that is. John Tavolacci's name sounds familiar. Does he have a hopped up V11 Rosso Mandello? Do you think that's a conservative dyno?

 

John mentioned a bike he owned, but to be honest, he showed me so many dyno runs, I don't recall which was his.

 

Based on his comments and selection of the SAE correction factor, which is more conservative than other options used by other dyno facilities, I believe it is pretty accurate. It deducted 1% from the actual output of 76.8 HP.

 

The AFR graph is a little hard to read on the post, so here are some data points:

The red dotted line is at 13:1. The peaks are 13.9 at 2600 RPM, 13.8 at 3900, 13.85 at 6300 RPM, 13.5 at peak power 7300 RPM

 

My guidance to John was that I was interested in increased range (MPG), that more power is always welcome at WOT but I was quite happy with the bike's output as it was. Max HP was not the goal. The AFR was higher at throttle openings in the cruise range. Generally from 13.9 to 14.4, except during decels, when it jumped way up briefly.

 

Given my objectives and the results, John honestly indicated that investing in a PCIII would not be worthwhile in my case. He could have easily taken advantage of me, as I'm a pushover for technology. Next time I feel compelled to tinker, or make some major change, I'll be back to him to make a purchase.

 

While I was there, he installed a PCIII on another bike along with a shift lever sensor. The PCIII momentarily interrupts the spark as soon as it detects motion on the shift lever. The duration is programmable. While on the dyno, he showed the customer how incredibly fast the bike could be upshifted at WOT. Instantaneous (less than 65 milliseconds) upshift as fast as one hit the shift lever. It worked like the best drag bikes-way cool! Warnings were given to the customer to avoid doing this in lower gears. (this bike dyno'd at 173 HP at the wheel! It would probably do backflips power shifting up to 2nd or 3rd.

[Ryland3210]

My 02 Lemans ran perfect, but after opening up the airbox, I decided to pun on an older serial PCIII. I have mistral pipes, an FBF x-over and modded airbox. Before mapping, it made a healthy 77 bhp, after mapping (and this was at 2600 ft elevation), it made nearly 85 bhp, and was the strongest running guzzi I have ever ridden, it wheelied very easy (roper sloppage plate installed) and got better mileage as well. Louie knows the guzzi's well, and really dialed it in. It still shows a dip, but it was so strong, you never noticed anything but horsepower and torque

 

Looks great.

 

Do you have any AFR plots to go with it? Was it corrected for temperature, barometric pressure and humidity?

[leafman60]

Wait a minute, wait a minute, what Guzzi makes 173 HP ????? Must have been an Eldorado.

[Ryland3210]

That is the flattest stock lambda curve that I have seen.

While a little lean compared to what most tune to to get maximum power, it is probably a good compromise for maximizing fuel efficiency.

Should you be concerned about heat?

Compare it the curves in the forum's dyno gallery

http://www.v11lemans.com/forums/index.php?showtopic=8556

Please consider adding your dyno there.

 

Why is the AFR so flat? All I can say is that shortly before the run, the valves, TPS, and synch were done carefully. The rest of the credit goes to factory mapping and whatever contribution the mod's may have made.

 

Should I be concerned about heat? Not according to John T., under these tuning conditions. The cruise AFR never got above 14.5. I think I'm OK.

I posted the chart as you suggested in the dyno gallery.

 

I'm looking forward to Sunday's ride with my buddies in the Polar Bear Club. Weather looks good for the middle of winter. We've had a good rainfall to wash off the salt, and looks like it will be dry through Sunday night.

[dlaing]

If you increase timing advance you can get another 2.5% or so from a stock motor. Any more of an increase typically requires engine mods. These figures are across the board generalizations that apply to most roadgoing four stroke internal combustion engines (cars, trucks, bikes, quads, etc.).

Motoguzzinix got more power by decreasing timing. So our bikes seem to be an exception to the generalization.

Usually, when we map/tune for midrange, it's at a slight loss to top end power, at least 5% or more, and vice-versa. The midrange dip/rough spot Guzzis have is best cured by a little richness in my experience.

How would mapping for midrange compromise top end power?

 

There are other, perhaps better, ways to cure the midrange dip then enrichening. The most popular way is adding an aftermarket crossover, and then remapping with a PCIII.

I suspect the dip may be a good place to lean it out or modify timing. According to Motoguzznix's research the A:F ratio is balanced across the cylinders at the dip. This gives it more room for making it run hotter there to get more power. Leaner may actually improve it there. Many dyno tuners have enriched there without much benefit. Finding the ideal timing for the dip could be key.

[Ryland3210]

Wait a minute, wait a minute, what Guzzi makes 173 HP ????? Must have been an Eldorado.

 

It was a four cylinder crotch rocket of some form. Tricked out, stroked, bored, and a $5,000 exhaust system. Definitely not a Guzzi!