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Discussion Starter #3
Well, kind of hard to explain. I assumed everyone must have had that or something. For instance going into a corner, I have to have my speed dead on, if I go into it too slow, I don't dare open it up because it has an abrupt power surge/delivery that can upset the bike. On my Duc, I can do just about anything with the throttle (kind of idiot proof) and it powers through smoothly. That's kind of why I have decided against taking the MV to the track and continue taking the Duc to the track. When I try to open it while existing from corners, I have to make a super concious effort to move the throttle very, very slow and smooth. I was hoping to smooth out the delivery so I don't have to freak out trying to blast out of corners!
 

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Hi Kamran,
sounds like your bike needs to have a co2 and TPS check up.

I shuffered from the same problems ,as I'm shure James C will also suggest, try 4.5% co. Both my bikes like that setting and after having TPS set correctly the motors will hold revs on the overrun into corners and drive out hard as you dare.

Cool looking bike by the way! :smoking:
 

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macmivvi said:
Hi Kamran,
sounds like your bike needs to have a co2 and TPS check up
:king: that man :)


We've called it 'throttle abruptness' over time I guess. Glad to hear it was just this and not something physical, though I know it can feel physical - almost like a vacuum suction is holding the butterfly closed. Glad to hear you are riding hard enough to turn this up :smoking:

I bought a sync tool and an exhaust gas analyzer some time back and can say with 100% certainty after a lot of playing around that you can introduce or eliminate this feeling depending on setup. If it's nearly time for a valve check then do that first (out of spec valves nullify correct numbers), followed by the throttle body balance and CO.

Here are my suggestions for elimination:
-open Exhaust
-clean filter
-Valves in spec
-Throttle bodies balanced very carefully and keep screws withing spec
-CO at 4.5% for my bike
-CR9EIX NGK plugs

I find you need to do this sooner than every valve check, it can drift out of spec from 3000-5000miles (a few times much sooner) in my experience.
 

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Discussion Starter #7
Thanks for your input guys, and thanks James for the instructions. I have about 5700 miles on it and will be taking it for service this summer. I'll hand them the list and put them to work...!

mamivvi, thanks for the comps, and I love the background where you took the pictures (the ones with the flowers and the rustic backgrounds). Is that your property? Very beautiful... :king:
 

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Exhaust Gas Readings

Folks, I wonder if this thread is dead?

If not, may I ask some tuning questions? I noticed that some people are suggesting % CO of 4.5%. Can you tell me if you are looking at other parameters, such as CO2, HC's and O2?

I just replaced my AGO's original RG3 chip with a new one developed by Ferracci (Thanks Sam at Corse Superbikes!), and was setting up the CO to minimize it, plus maximize CO2 (best efficiency). The following numbers, which had the exhaust smelling very rich, were obtained before adjusting anything:

CO-------CO2-------HC---------O2
%---------%--------PPM--------%
4.4........7.41........600..........5.7

(Nose gas analyzer says this is pretty stinkin' rich)

I leaned to stumbling idle


CO-------CO2-------HC---------O2
%---------%--------PPM--------%
1.15......9.45........400...........6

Then enrichened slightly


CO-------CO2-------HC---------O2
%---------%--------PPM--------%
1.06......9.70........400..........5.35

Then looked for smoothest idle near this number (slight tweak of the pot)


CO-------CO2-------HC---------O2
%---------%--------PPM--------%
0.71......10.05.......426.........5.5

(Using the nose gas analyzer, the exhaust smells like good complete combustion- no over-rich smell)

I was surprised to see your notes indicating that 4.5 %, or there about, is best. I do note that the throttle response with my last figures is very sharp- blip the throttle and the RPM is at 6000 in an instant. I also ran the throttle up slowly, all the way to 8000 RPM (the previous PROM had a nasty bucking cut-out between 7000 and 8000 RPM), and found the engine was smooth all the way up and down. I have not put any miles on the bike yet- that will have to wait until next weekend.

As I am brand new to tuning up motorcycles with a gas analyzer, I am not sure what I am shooting for here. I read an article I found on the 'net from Toyota about setting for best CO2, and enrichening slightly to be in the stochiometric (~14.7:1 Air/Fuel ratio) burning range.

Note the high HC's- I don't have the catalytic converter in during this test. Do these HC's seem abnormally high to you?

Thanks for any comments/suggestions you can make.

Sincerely,
Shane
 

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On my 910R, when you get back on the gas slowly, it feels like the bike slows down a little, or "pauses" for a split second befor picking up power.
When I had the bike on the dyno, I tied replicating this and I found that when you are cracking the throttle, say 2-5%, a lean condition in the map shows up.
I added some fuel at these throttle positions and it help with the transition.

I will be tweaking the PC map some more to see if I can eliminate it completely.

So, James C and others are correct that is mostly a fueling issue. But do check the basics first.

John T
 

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Shane said:
I read an article I found on the 'net from Toyota about setting for best CO2, and enrichening slightly to be in the stochiometric (~14.7:1 Air/Fuel ratio) burning range.
Sincerely,
Shane
These are not car engines and if you shoot for 14.7:1, you will be down on power, heat will rise sharply and the bike will run like crap.

Best power for most engines is in the 12.8-13.2:1 ratio. BMW motorcycle engines shoot for this 14.7 range in the closed loop area and it causes the infamous Beemer surge...actually it is a lean misfire.

Better to be richer than lean.

John T
 

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Rtfm...

WELL, folks, I bought the manuals for the AGO, but I couldn't find ADJUST CO... until I looked for synching the throttlebodies... And the answer is: CO is to be set at 3.5 +/- 0.5 %...

Now I need a mercury gauge set...


Shane
 

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Update

John, Thank you very much for the map between CO levels and Air/Fuel ratios. This will be very helpful.

After I READ THE MANUAL, I realized I should not take it for granted that the previous owner/maintainer had set the throttle body balance, so I went to my friendly local Cycle Gear, and picked up a mercury synchronizer gauge. I put the synchronizer on, and found that the throttle bodies actually weren't all that synched. In the manual, it speaks of the minimum position for the bypass screws on each throttle body is one turn out from fuilly in. The maximum allowable adjustment is three and 1/2 turns out from fully in. As an initial condition, I checked each throttle body- counted the number of rotations to the right to th e fully-in position. Throttle Body (TB) 1 was exactly 1 1/2 turns, as was TB2, and TB4. TB3, however, was somewhere between 1/4 and 1/2 turn from closed (fully in). After probably 40-50 minutes, as I was jockying for level mercury columns in all four tubes, I suddenly realized I had bottomed out #2. That caused me to re-evaluate the initial position recommended by the shop manual (1 1/2 turn from fully in), and I tried 2 full turns, then 2 1/2 full turns, which resulted in the best synchronization I could obtain over a couple of hours of effort. (Starting at less than 2 1/2 turns doesn't allow me enough adjustment on my bike to stay above 1-turn out from fully-in on the "lowest bypass" TB, which is a requirement in the manual.)

With the TBs synchronized, I could finally get back to setting the CO. As the manual specifies 3.5 % +/- 0.5 %, I decided to make 3.5% CO my target, as we have mountains here in Arizona where one doesn't want to be running too rich, and, as I live in the desert, which is 1300+ feet above sea level, as well as I may make a trek to San Diego, or L.A. sometime, I don't want to have to worry about the thing being too lean there, either. I was able to attain this value, and here are the values of the other components of the exhaust gas:

CO... 3.52 %
CO2.. 8.78 %
HC... 539 ppm
O2... 3.8 %

If anyone decides to follow me here, a word of caution: make adjustments very carefully. moving the adjustment screws 1/8 turn or less at a time is required to keep from passing through the "sweet spot". Coarser adjustment can take you past the sweet spot, and you might never notice it. Same goes for the CO control. Also, there are two ways to increase CO output- one is below (lean side) the optimum A/F ratio, and one is above it (rich side). You'll want the rich-side adjustment. The engine doesn't like the lean-side one.

Ridability- I have not taken this thing out yet, but I did notice that the throttle response is very, very snappy- blip the throttle, and it zooms past 4-5000 RPM.

Good luck, good tuning , and happy riding!

Shane
 

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Hi Shane,

Good work! Have you read through the faq pages to compliment what you've learned from the manual?

http://mvfaq.blogspot.com/2005/12/tuning-1-throttle-position-sensor-tps.html
then most relative to your work so far:

http://mvfaq.blogspot.com/2005/12/tuning-2-idle-base-co-and-throttle.html



For example you mention that your #2 cyl was found bottomed during your sync work and on the 1000's this is the base by which you set the rest against. My suggestion is to try to have a look relative to number two by first setting IT in a reasonably middle ground before touching the others THEN move on to 1,3,4. Because of EBS you have to set #2 then align the others to this placement. No mention but you may have done it this way? If not it will need to be done again IMO - or at least checked for turns in/out.

I only use a single gas analyzer, CO. I haven't checked my other numbers on a 5 gas so can't help there.

I will say though, as I mentioned on the FAQ page, the factory specifies 3.5% as an EU mandate on emissions where in fact most people who work on this subject find 4.5% to be much more controllable on the throttle with a good balance of all factors considered.

If you were mapping a PCIII, for example, I would say to make sure of all the base setups (as airfuel mentioned) which includes filter clean, valves in spec, tps then your throttle bodies and CO%.

I do the throttle bodies and CO% at about every oil change - I find that it drifts 'out of spec' a bit before this point but I find it easier to do them all together. Now that you've done it once you'll find it takes only minutes in the future for the throttle bodies and it takes much longer to flip the ECU than it does to actually adjust the CO% into range :)
 

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Update #2

JamesC said:
Hi Shane,

Good work! Have you read through the faq pages to compliment what you've learned from the manual?

http://mvfaq.blogspot.com/2005/12/tuning-1-throttle-position-sensor-tps.html
then most relative to your work so far:

http://mvfaq.blogspot.com/2005/12/tuning-2-idle-base-co-and-throttle.html



For example you mention that your #2 cyl was found bottomed during your sync work and on the 1000's this is the base by which you set the rest against. My suggestion is to try to have a look relative to number two by first setting IT in a reasonably middle ground before touching the others THEN move on to 1,3,4. Because of EBS you have to set #2 then align the others to this placement. No mention but you may have done it this way? If not it will need to be done again IMO - or at least checked for turns in/out.

I only use a single gas analyzer, CO. I haven't checked my other numbers on a 5 gas so can't help there.

I will say though, as I mentioned on the FAQ page, the factory specifies 3.5% as an EU mandate on emissions where in fact most people who work on this subject find 4.5% to be much more controllable on the throttle with a good balance of all factors considered.

If you were mapping a PCIII, for example, I would say to make sure of all the base setups (as airfuel mentioned) which includes filter clean, valves in spec, tps then your throttle bodies and CO%.

I do the throttle bodies and CO% at about every oil change - I find that it drifts 'out of spec' a bit before this point but I find it easier to do them all together. Now that you've done it once you'll find it takes only minutes in the future for the throttle bodies and it takes much longer to flip the ECU than it does to actually adjust the CO% into range :)
James,
Thank you for your post. I had not had a chance to ride the bike until yesterday. I found the temperature was higher now, by approximately 13 degrees, when the bike is on the freeway. Around town, it's staying right around 200 degrees, plus or minus five degrees. There's still the curious hessitation between 7000 and 8000 RPM, even with the latest PROM from Ferracci.

Now one thing here- when I was balancing the throttle bodies, I did not see the levels are perfectly even between all banks. I had them to within 1/4 inch or less of each other. What do you use as tolerance on the balancing? Do you get them perfectly aligned? Do any of them "bump" up and down, and when they do, cause purturbation in one or two of the other TB measurements? I notice the thing idles a lot more smoothly when the mercury guages are disconnected, and the caps restored on the vacuum ports.

So, it looks like I have verified your statements that the bike will run hotter when it runs leaner. BUT, I am wondering how precise I need to be with the balance, and if you find when yours is balanced, does it run smoothly (say, like an electric motor) with the vacuum gauges attached, when the balance is right? (I had a 1978 Honda 750Four that was like that- the idle sounded like crap until you stumbled across synch, then purred like a kitten). Is THAT what I'm looking for here? I was still under the weather last weekend when I attempted this, so I didn't have the patience to hunt around for probably another hour or two. :conveyer: :conveyer:

Thanks for your assistance, and words of advice and encouragement!

Shane
 

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HI Shane,

Mine are always a bit on the move. I find I just get a feel for the mean range of the up to down stroke and use that. I've never seen them perfectly still unless the gauge was at a severe angle and thus not working hahaha.

I use a Morgan carbtuneII which is solid rather than Mercury. I understand these fine movements are alse relative to the little damping valves you use but I like the fine information provided by the one which causes the constant movement. It's a bit of a feel and experience thing I guess but theoretically easy to understand. Make sure you take it up and down in revs to see how it looks at a few representative and repeatable points, Idle, 5k, 8k or whatever you choose. If using mercury careful not to shut the throttle too quickly or the vacuum will suck the mercury out of the tool and into the engine on some gauges!

I wouldn't expect it to behave as you described for the honda.

Again, i strongly strongly strongly suggest you follow factory suggestion as a MINIMUM at 3.5%. My suggestion of 4.5% is just what I've found helpful for smooth throttle after experimentation. I'd hate for it to be running too lean and burn expensive parts. I didn't look back but think I remember something less than 2% being mentioned..
 

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Mean, But Not Too Lean?

Hi James,

Thanks for your experiences. The MV manual states CO should be adjusted 3.5 +/- 0.5 %. I had adjusted to 3.52 %. After re-checking the synchronization, I will try setting the CO to 4% and see where the temperature settles. It may be next weekend before I have time to work with it again, but I will have another look at the synchronization. I also read your web article on synchronizing the throttle bodies. I will see about synching TB 2 to TB3, then TB1 to TB2, and TB4 to TB3. That's good to know. I will see if I have a right-angle ratchet/screwdriver tool that will allow the left bank/right bank assembly synchronization, as you documented.

Thank you again for your assistance! :drummer:

Shane
 

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No problem but Brad in OZ wrote the article. I just added tidbits here and there since it was originally written to be Brutale specific.

Best of luck. I've done a lot of experimentation between 3 and 7.5% CO so just relaying what I had found..YMMV and all that :)
 
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