dlaing

and I think Ryland's strategy is going to fill the mid-range hole effortlessly and the battle will be all about minimizing the high end losses while keeping the sound down and not losing low end. Perhaps I wrong, but I doubt it. Starting with a long center connector made of plain ugly automotive exhaust tubing, he could gradually cut it down to get the right tuning length, or he can do all the calculus(sorry, can't help there) and get it right the first shot . Or it may just not make much difference. Here is an interesting tuning experience http://www.visi.com/~moperfserv/hamelvincent.htm But I wish I could tell if that is two into one or two into two?????

Interesting... For 2008 they list Stelvio, 8V and Monza http://www2.solomoto.es/noticia.asp?ref=10092 Need more info

Thanks Emry! Any ideas how Ryland might calculate this independent header design? I tried some thumper sites looking for ideas, speculating that they might know how to design an exhaust without crossovers and two into ones. But I found nothing but aftermarket slip-on options, with SuperTrapp being an apparent frequent favorite. Thumper makers and most motorcycle makers seem to make the length of the exhaust fit the bike. 125cc-650cc, all about the same length, but diameter changes a bit. The Buell Blast might be an exception amongst singles, although the innards of the exhaust could go back and forth a couple of times increasing the tuning length. I wonder if the engineers even bother with tuning length? Enzo's Cobra was allegedly great for power, but it was loud and must have been a pain during oil changes. SORRY

No, you ingrate, my speculative nature has been of great value to this forum. Not all enjoy speculative banter. They prefer to sit back in their high chairs and swallow spoon fed crap. Not my cup of tea I suppose I should thank you for training me to use many of those listed words, as they are a defense mechanism against your attacks. A pity you are so bored that you took time to look every word that frustrated you in your endeavor to corner me when I make an error. But I am sure your adoring fans will be grateful for your diligent work and will give you an attaboy for pegging me so precisely. (Hey look, I only speculated once ) You can hook up a WBO2 to each exhaust pipe, before the X-over. The leanness tends to indicate that that cylinder is working harder at that RPM. (I have to use the speculative term 'tends' because there exceptions to the theory) Read the infamous ECU thread! Derrick Capito (spelling???) presents a compelling argument http://www.v11lemans.com/forums/index.php?...c=4152&st=0 Who do you suppose started that thread...

I must have missed your stating that you had that kit in your hand. Care to site the post number? Assuming you are correct, sorry for not reading properly. I see statements from you that appear to be incorrect information, like "He has many years of dealing directly with Brembo and categorically states that there are NO - REPEAT NO - specific seal/refurb kits available for the Brembo P32B or other P32 Goldline series 'racing' style calipers from Brembo themselves" When clearly several places show seals for the P32B available for sale.

I have trouble understanding tuning length theory. Trial and error probably works better. My rough measurement is that it is about seven feet (between a quarter and a fifth of a wave length at 4000RPM)from exhaust valve to the outlet of my Mistral muffler. The stock muffler is has nearly three times the tuning length of the Mistral' muffler section, so add on about maybe five more feet giving a length of about 12 feet, or maybe a third of the wave length. at 4000RPM. Maybe if the exhaust was just over 8 feet for a quarter wave, the hole at 4000RPM would magically go away, but I doubt it At maximum Torque, 5250RPM, the seven foot would be about a quarter wave length and at 12 feet would be about 2/5 wave length(surprised that works well) At 8000RPM seven feet would be about 7/16 of a wave length and 12 feet is about 3/4 wave length, both pretty good for making peak HP, perhaps an 8.25 foot exhaust would make ideal power at 8000RPM, But I'll be 12.3 foot is fine too, and the loss of power is from the restrictiveness of the stock muffler, not the tuning length. Aside from the hole in the torque curve at 4000 RPM, it is a fine curve. Way to go Luigi! According to Motoguzznix's Dyno work, there is an appearance that the left cylinder pulls harder till 4000RPM where both cylinders pull equally but power is disappointing and then the right cylinder pulls harder until they balance again at maximum torque point of 5250RPM, and then it switches back to the left cylinder pulling harder. Presumably the wave of boost is working best 5250RPM and worst at 4000RPM, a difference of 1250 RPM. You will find this same effect with either the OEM or typical aftermarket slip-ons, both of very different tuning length.

I'll betcha it is the 120.2799.30 seal, "part of an OBSOLETED caliper, the P32B #20.4532.70 caliper". One of these days someone will spend the $9.76 ++ and find out(yoyo has $25minimum order). I suppose asking won't hurt... I suspect another viable source is Guzzitech. Yes, I am spamming for them and I ride and eat lunch with Todd Eagan. But it would be good to support Guzzi specialists over every other yoyo out there, if we have a choice.

I doubt it, but hey, you never know. I sure was surprised to learn from your posts that the mixture was perfectly balanced at 4000RPM. Effects of back pressure are fairly easy to predict. Effects of tuning length are more difficult to predict. With the crossover all evidence is that the stock muffler does not lose low end and may in fact gain it over what is typically used, free-er flowing shorter tuning length muffers that give the bike more high RPM power. Predicting that the same will happen without a crossover, where we are potentially getting more back pressure, does not seem to be making a risky prediction. I suppose the back pressure with stock muffler and no crossover might produce so much back pressure that the power is robbed below 4500RPM but I doubt it, and I am positive it won't gain more power above 6500RPM and will likely lose a lot. Going to the free flowing mufflers, back pressure is pointing us at less bottom end and more top end. I don't think that is a bold prediction. If I said that no crossover and free flowing muffers would make more power in the low end, mid range or the high end than a typical stucchi/mistral combo, that would be a bold prediction. I think such an arrangement will make less overall power but I have no idea where it might do better or worse. Yah, I know, another bold prediction. I hope Ryland proves it wrong

If you lose the headlight (Low or high, not the 10W dip light) when the tach goes out, followed by charging problems, it most likely indicates that the starter or headlight relay is going bad. Motoguzznix mentioned this in the other thread. Next time it happens put your hand in front of the headlight and see if is lit. Also, check if horn works. If both are out, than you need relays. You can get the best amp rated relays here, for cheap: http://www.dpguzzi.com/relay.htm

That presents a good argument for sticking with the stock airbox and using a crossover. I suppose you could have shields to deflect the wind and balance tubes to even the airpressure by the pods. But that would be a pain to implement so that it worked well.

FWIW There still may be some discrepencies, but I don't think it has anything to do with the model year. One error is the polarity on the left front turn lamp (not of great importance, but it might confuse someone plugging in an LED bulb) A while ago, I sent Carl a list of what I discovered. I think he fixed the other discrepancies. As always, Thanks Carl! I might have sold my bike a long time ago if I had to rely on the diagram in the manual.

Hi Pierre, I am almost certain the TuneBoy won't communicate with the Breva, Griso, Norge, etc. Those bikes use a Magneti Marelli IAW 5 AM2 or something like that...maybe it is a 5AM? I would not be surprised if TechnoResearch soon comes out with a Direct Link software to use with the Newer bike's ECUs. It appears as if their diagnostic software may work with it, but Guzzitech does not list it. But it is listed here http://technoresearch.online.fr/Motorcycle-List.htm The diagnostic won't show the mapping, only the direct link. Not sure about AxeOne, but I doubt it will show the mapping.

For $205US http://www.guzzitech.com/store/TR-DirectLink.html DirectLink can modify fuel maps for each cylinder. I think Tuneboy can, but the map labels have me a little confused. PCIII USB can do individual cylinder tuning, but not timing. For a few more hundred dollars you can get a wide band Oxygen sensor, preferably with data logging so that you can use while riding. An exhaust gas temperature meter can also be useful. I think the further you go from stock with modifications, the more you will benefit from these tools. Motoguzzinix's posts show that there is room for improvement for just about any V11. Going with separate exhausts will really change the mapping needs. You might also consider pod filters to keep the cylinders even safer from cross-interference.

I don't understand that either. I thought the Boxer twins would benefit even more from a 2 into 1 because of the symmetry. That is what I believe. Yes, you have to weigh the benefits of shared muffler for scavenging versus the benefits of clean even back-pressure. Keep in mind the stock ECU is mapped for the stock mufflers and crossover. Throw a Stucchi on and some more open mufflers and all that hard work plotting the map cells by the factory engineers has gone out the window. I have yet to see someone post a really extensive mapping that truly got the most out of the modifications. Also, keep in mind that without a crossover, you will lose power somewhere... With Guzzi stock muffers and no crossover, expect big gains in the middle and bigger losses at higher RPM. I suspect if you put on the free-est flowing mufflers you can find, the high RPMs benefit while the low-end will drop miserably. But find the right compromise and re-tune the ECU and you have one of the smoothest running Guzzis around. Just don't expect to win races against the bikes with Stucchi Crossovers and Mistral Mufflers, that have already been proven to make power.

Yeah, that is why I suggest a crossover as CURE for the flat spot. The Quat-D and Mistral were compromises, but the Stucchi and FBF had gains just about everywhere.

Yes, there are other factors, and the waves that engine generates are not caused by the exhaust but their reverberations and how they move are greatly effected by the exhaust. But replacing the crossover gets rid of 50 to 120% of the flat spot. FBF Stucchi and Quat-D seem to get rid of just under 100% of the dip. Mistrals seem to get rid of more than 100% of the dip. Re-positioning the crossover might have an even greater effect. EDIT How much of the flat spot is removed is relative to how you define a flat spot. To my mind if the HP is flat or downward, that is a flat spot. Dips in the torque curve are not necessarily flat spots After defining it that way, I can say that the FBF, Stucchi and Quat D in most cases remove that flat spot completely. Although there is still less increase in HP through the 4000 RPM range.

I sure hope you are wrong. Still I can imagine it would still be a nicer ride than most 600 fours. Without shame, I think BMW is the one to follow for power curve design. I'll bet this Griso will be pretty close to a BMW R1200's power curve. Personally I like the curve of the R1200S EDIT Here are some interesting dyno charts Kind of interesting how many flat spots are on the R1200ST curve. http://www.moto-one.com.au/performance/r1200s_st.html http://www.moto-one.com.au/performance/v11sport.html http://www.moto-one.com.au/performance/1098dptermihomo.html

I agree. There is plenty of room for optimization of the timing. Judging by the graphs there is also plenty of room to optimize the individual cylinders. I still have to get my second hand wide band sensor working But using your output as a guide I can at least make some changes at WOT. Thanks!

The stock crossover appears to be the cause of the flatspot. Guzzi could have put a simple X cross over, but they wanted something that would also help it pass noise tests, so they created the baffled stock crossover, and thus the flat spot appear to be the result. They could have used an X-over and quieter mufflers to obtain the same sound but that would likely have reduced top end power, making it less marketable. I suppose the flat spot in the middle allows them to run leaner and or with more advance at that point, perhaps helping pass emission testing???

The stock map from my ECU as interpreted by my Tune Boy software I graphed the 84.56% throttle data across all the RPMs. I spaced the spread sheet entries so that curve would show. It is not perfectly accurate in the spacing of the bars for some reason But the curve gives a pretty good indication. Tuneboy has 3D graphing capability, maybe I will post. I need a new usb memory stick so I can shuttle between garage PC and internet connected Mac. The upper row of the upper map in this image is what was graphed

Throttle position is clearly the most important indicator that the ECU on our bikes uses to guess how much air will actually be delivered. Of course, throttle position does not accurately measure how much air is actually delivered. But combined with other information from other sensors, it can estimate well enough for the bike to miraculously run! Of course everyone else is essentially correct too. So what are we arguing about? probably semantics, again...

At 4000RPM, one of the few points where I expected to see left right not balanced, is exactly where it balances. I guess the fact that it switches over there and at 5200RPM may indicate that something is happening with the exhaust waves, but interestingly at 5200 it just about makes maximum torque while at 4000 performance is lame. Probably would not hurt to run it a little leaner at 4000, just to keep it cleaner, afterall, whatever you do there does not effect power.

Oh Fun! Another thread on relativism!!!! Flat spots can be caused by many things. Postings of dyno tuner's experiences on this forum have shown that changing fueling across both cylinders does little to reduce the flat spot. Postings here have also indicated that starting in 2003 Guzzi fixed the flat spot with a balance pipe and other alleged changes.. And of course aftermarket crossovers and the Quat D have been shown to virtually eliminate it, sometimes at the expense of top end. I kind of like the exhilaration of leaving the flat spot!!! It may be possible to fix the flat spot with ignition advance and individual cylinder fuel tuning???? EDIT after examining the ignition advance curve, the hump is right about where the hole is.(get your mind out of gutter) Did Guzzi try to fix hole with advance or was the hole aggravated by too much advance? Or maybe it needs MORE advance???? Sorry image too large...and linearity of curve is a little warped do to my inability to use NeoOffice, based on Open Office.

I have had that happen and it was fixed by a tune up. (adjust valves, then TPS, then balance TBs) I think the "cause" was an exhaust valve being too tight.

Interesting idea, but the TPS model won't help, at least not at WOT, which is where it shows up in the dyno chart. But mid throttle is a possibility, although unlikely.