TX REDNECK (R.I.P.) Posted January 9, 2006 Posted January 9, 2006 Has anyone tried pulling the fuel injectors out and cleaning them????? Carl has a story to tell & he just happens to have a lifetime supply of those little screens too
Guzzirider Posted January 9, 2006 Posted January 9, 2006 What are the advantages or dissadvantages on using an 100Octane gas on the Guzzi? 73867[/snapback] I have just tried it the once on a long Autobahn joureny down the A61 to the Black Forest. Bike did not pink at all and I it could have been my imagination but the motor seemed to enjoy that extra octane. Guy
Guest jmnvhc Posted January 9, 2006 Posted January 9, 2006 The Germans have the right idea- they sell 100 octane from the pump (Shell V Power). Guy 73812[/snapback] This is something that I don't understand about v11 Guzzis... why they even require high octane in the first place. The compression ratio is 9.8:1, which isn't high. Higher octane fuels came about as a result of higher compression (read higher performance) engines, which the Guzzi is not (not complaining). It just shouldn't have a problem with lower octane fuels, right? I don't know, maybe the timing is really early on it, or maybe since it's air-cooled on hot days it just detonates because it runs hot?
dangerous Posted January 9, 2006 Author Posted January 9, 2006 PSIs your bike stock or modified? 73779[/snapback] Only change is open pipes, but not to open.... they have been on since almost new and I havent had the pinking this bad till now. NZ fuel is shit..... so Ill try the higher oct, however it is the same shit as 91 but with more shit additives... my 1100i sport never pinked on 91oct, TPS.... interesting might have to look at that.
dlaing Posted January 10, 2006 Posted January 10, 2006 Now it ranges to 32-34 in town driving.Used to be about 39 and with the previus exausts about 44mpg. I think your conversion is wrong. You previously said that you were consuming 12 to 14 liters per 100 km, which would be about 18 miles per US gallon or 22 miles per imperial gallon.
Guest Nogbad Posted January 10, 2006 Posted January 10, 2006 This is something that I don't understand about v11 Guzzis... why they even require high octane in the first place. The compression ratio is 9.8:1, which isn't high. Higher octane fuels came about as a result of higher compression (read higher performance) engines, which the Guzzi is not (not complaining). It just shouldn't have a problem with lower octane fuels, right? I don't know, maybe the timing is really early on it, or maybe since it's air-cooled on hot days it just detonates because it runs hot? 73880[/snapback] Whether an engine detonates is not just to do with compression ratio. There are many other considerations like the effectiveness of mixing, swirl in the combustion chamber, siting of the spark plug, whether the valves run hot, ignition timing etc. etc etc. My take on it is that it is an old design of engine, with poor mixing and a long flame path being forced to run very lean for reasons of legislation. It may also not have the best developed ignition map. Petrol has changed a lot over the years too, and modern unleaded is not the same substance as was there when the Guzzi was designed. Running higher octane fuel makes a lot of difference to mine, in the UK I use Shell Optimax (98 RON) or BP Ultimate (97 RON). Weirdly, the BP fuel runs better.
g.forrest Posted January 10, 2006 Posted January 10, 2006 i run on standard unleaded here , me think it 92.. with 11.3 compression, but is liquid cooled. have even tryed to get it to ping, pulling throttle open at low revs in hot conditions under load of steep grade. but it will never ping. but it's not a guzzi.. Whether an engine detonates is not just to do with compression ratio. There are many other considerations like the effectiveness of mixing, swirl in the combustion chamber, siting of the spark plug, whether the valves run hot, ignition timing etc. etc etc. My take on it is that it is an old design of engine, with poor mixing and a long flame path being forced to run very lean for reasons of legislation. It may also not have the best developed ignition map. Petrol has changed a lot over the years too, and modern unleaded is not the same substance as was there when the Guzzi was designed. Running higher octane fuel makes a lot of difference to mine, in the UK I use Shell Optimax (98 RON) or BP Ultimate (97 RON). Weirdly, the BP fuel runs better. 73922[/snapback]
docc Posted January 10, 2006 Posted January 10, 2006 This is something that I don't understand about v11 Guzzis... why they even require high octane in the first place. 73880[/snapback] The air cooled motor with very large pistons can allow hot spots which initiate pre-ignition ( not good). Running more octane, or more fuel (better cooling) can eliminate the pre-ignition. The state of tune on these motors is fairly complex such that it amazes me some of you can run on low octane fuel. Pinging that comes on fairly suddenly still sounds to me like a tank of crappy gas.
Cliff Posted January 10, 2006 Posted January 10, 2006 Pinging that comes on fairly suddenly still sounds to me like a tank of crappy gas. 73941[/snapback] It is usually a result of opening the throttle. This has the effect of moving from one area in the map to another - where timing, mixture and load is more conducive to pinging. I been running both my bikes on unleaded for a time without any problems. However I've since moved back to Optimax. Only because I figure if I tune it specifically for the fuel, a 10% improvement in economy will pay for itself. A 10% increase in range is always handy.
dlaing Posted January 11, 2006 Posted January 11, 2006 It is usually a result of opening the throttle. This has the effect of moving from one area in the map to another - where timing, mixture and load is more conducive to pinging. 73977[/snapback] I have found that my pinging seems to continue after the throttle has been opened. My bike with the ECU unmodified pings from about 4500 to 5500 RPM at WOT (and other large throttle openings). So, when I am going up a steep hill in sixth gear at 4000 RPMs and I whack open the throttle, I accellerate initially without pinging, and then ping from about 4500 to 5500 rpms. But if I I am going up a steep hill in sixth gear at 4500 RPMs and I whack open the throttle, I ping immediately and continue to ping from about 4500 to 5500 rpms. I don't know if my bike is just like Motoguzznix', but his graph shows SOME leaness in the area where mine pings. I never ping at 3000 rpm but Motoguzznix does. I guess I have to get a WBO2 to do my own logging
dangerous Posted January 11, 2006 Author Posted January 11, 2006 The state of tune on these motors is fairly complex such that it amazes me some of you can run on low octane fuel. It's what the book in the boot says to run it on.... having said that NZ fuel is amongest the worst in the world and 91oct often comes in at 89+/- 3oct I have found that my pinging seems to continue after the throttle has been opened.My bike with the ECU unmodified pings from about 4500 to 5500 RPM at WOT (and other large throttle openings). So, when I am going up a steep hill in sixth gear at 4000 RPMs and I whack open the throttle, I accellerate initially without pinging, and then ping from about 4500 to 5500 rpms. But if I I am going up a steep hill in sixth gear at 4500 RPMs and I whack open the throttle, I ping immediately and continue to ping from about 4500 to 5500 rpms. I don't know if my bike is just like Motoguzznix', but his graph shows SOME leaness in the area where mine pings. Same, same, same......... Now the girlfriend comented to me her bike was doing the same (Buell XB12R) and I took it for a spin and yes it is just not as bad.... now the last to days I have ridden it has been very hot and we used the same fuel 91oct... we are leaving in the morning for a rally 500k away and will run both bikes on 98 or 96 were 98 isent avaible.... will report back next week. Cheers for all the help
Skeeve Posted January 12, 2006 Posted January 12, 2006 This is something that I don't understand about v11 Guzzis... why they even require high octane in the first place. The compression ratio is 9.8:1, which isn't high. Higher octane fuels came about as a result of higher compression (read higher performance) engines, which the Guzzi is not (not complaining). It just shouldn't have a problem with lower octane fuels, right? I don't know, maybe the timing is really early on it, or maybe since it's air-cooled on hot days it just detonates because it runs hot? 73880[/snapback] #1: Air-cooling. Air-cooled engines have always had lower CR's than their liquid-cooled brethren. Think about the highest CR you heard about in the SuziQ Gixxers before they moved from the air&oil-cooled SACS engine [which lives on in the Bandit] to the water-pumpers; what, 11:1 vs. nowadays, 12.5? 13:1? And those are I-4s... #2: Cylinder diameter. Let's take an example where the engines have the same stroke, to make the math easier: a 1000cc I4 has 4 cylinders of 250cc, a 1000cc V2 has 2 cyls of 500cc each; the diameter of the V2 pistons is going to be about 1.4x the diameter of the I4. That means that the timing has to have more advanced to create a complete burn at similar rpm, which means that you're that much closer to pinging. Retard the timing, pinging is less likely, but you generate more heat & less power [at least, that's my understanding of it!] #3: Hemi head. Hemi's are great when you have 4v heads w/ a central sparkplug & great intake tract design for good mixing. They bite when dealing w/ 2v heads with their offset plugs, large valves, and not-so-great intake tracts that don't flow & fill as well as they might... The dual-plugging of the latest iteration of the Guzzi big-block is just a band-aid for this antiquated hemi-head design. Ride on!
dlaing Posted January 12, 2006 Posted January 12, 2006 #1: Air-cooling. Air-cooled engines have always had lower CR's than their liquid-cooled brethren. Think about the highest CR you heard about in the SuziQ Gixxers before they moved from the air&oil-cooled SACS engine [which lives on in the Bandit] to the water-pumpers; what, 11:1 vs. nowadays, 12.5? 13:1? And those are I-4s... #2: Cylinder diameter. Let's take an example where the engines have the same stroke, to make the math easier: a 1000cc I4 has 4 cylinders of 250cc, a 1000cc V2 has 2 cyls of 500cc each; the diameter of the V2 pistons is going to be about 1.4x the diameter of the I4. That means that the timing has to have more advanced to create a complete burn at similar rpm, which means that you're that much closer to pinging. Retard the timing, pinging is less likely, but you generate more heat & less power [at least, that's my understanding of it!] #3: Hemi head. Hemi's are great when you have 4v heads w/ a central sparkplug & great intake tract design for good mixing. They bite when dealing w/ 2v heads with their offset plugs, large valves, and not-so-great intake tracts that don't flow & fill as well as they might... The dual-plugging of the latest iteration of the Guzzi big-block is just a band-aid for this antiquated hemi-head design. Ride on! 74118[/snapback] #4 Bad fuel map. (I wonder how many PCIIIs have been sold in the world?!?)
Skeeve Posted January 14, 2006 Posted January 14, 2006 #4 Bad fuel map. (I wonder how many PCIIIs have been sold in the world?!?) 74120[/snapback] Well, yeah: there is that!
dlaing Posted March 23, 2006 Posted March 23, 2006 snip... and will run both bikes on 98 or 96 were 98 isent avaible.... will report back next week. 74090[/snapback] ...and the verdict is???
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now