Hotrodding the GS

  


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Yup. Exactly what I experienced on my first ride with the Air today. Smooth with quick response to throttle. Very nice guys

I'm looking forward to trying mine this Spring. Ordered in July and got it today (5 1/2 months from order to door) Hopefully the Ice Cool and Smooth will take less time to build.

I'm sure you'll like it once you dig out into Spring. Either way yes, the wait on your batch will to be hard to beat! Not that I'm trying or anything.

Happy Holidays folks!


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Here's some information relating to fuel injector atomization and fuel pressure, and how they relate to fuel vaporization.

Atomization doesn't much change the fuel vaporization rate within the atmosphere of the intake tract. But the increased fuel pressure likely creates a somewhat larger spray pattern, and that would make a difference.

The sequence of events goes sort of like this. Fuel leaves the injector, flies through the air, and lands on the intake port wall where it begins to vaporize. That waiting-to-vaporize fuel is often referred to as 'port wall fuel'. That 'puddle' of fuel if you will, covers some amount of surface area on the intake port wall. The vaporization rate of the 'port wall fuel' is primarily based on the surface temperature of the wall.

After spraying from the injector nozzle, some of the sprayed fuel vaporizes due to the low pressure of the intake manifold. The low pressure vaporization rate is based on manifold pressure and is not significantly dependent on fuel droplet size (aka atomization.)

The remaining bulk of the sprayed fuel vaporizes after coming into contact with the warm inside walls of the throttle body and intake port. That particular vaporization rate is based on a few things. Manifold pressure continues to be a minor factor in fuel vaporization rate, but there are three other larger factors.&#8194;1. The temperature of the inside walls of the throttle body and intake port.&#8194;2. The the total area of the injector spray pattern.&#8194;3. The velocity of the intake air across the 'port wall fuel puddle'.


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Here's some more info on fuel vaporization.

The thing is, in the intake tract, gasoline turns to vapor primarily via two processes. In one process the liquid gasoline is heated and turns to vapor from being in direct contact with the intake port wall. In the other process the liquid gasoline vaporizes due to the low pressure of the intake port during the intake stroke.

There are some reasons why 'heat vaporization' plays a more significant role than 'low pressure vaporization' in vaporizing the liquid gasoline.

1. 'Heat vaporization' happens during the entire 720° of the combustion cycle. That is to say, liquid gasoline vaporizes during the whole time it's in contact with the intake port wall. I mean, once all the liquid gasoline 'boils off into a vapor' the heat vaporization process is complete of course. But as long as liquid gasoline is present on the intake port wall the process happens continuously.

2. 'Heat vaporization' is permanent. Meaning that the heat-vaporized fuel doesn't re-condense to a liquid at some point further along in the 720° combustion cycle.

3. 'Low pressure vaporization' is semi-permanent say, and primarily for the two reasons described in item 3 and 4. On an Independent Throttle Body motor, low pressure vaporization only happens during a fraction of the 720° combustion cycle. Specifically, it only occurs during the period of time the intake port is at a pressure low enough that the gasoline can no longer remain a liquid. In practical terms, that's about 120° of crankshaft revolution, less than half a turn. As compared to the two revolutions (720°) of the full combustion cycle.

4. 'Low pressure vaporization' is in some ways a temporary phenomenon. Some of the liquid fuel vaporizes during the low-pressure period of the intake stroke, only to re-condense into a liquid when the manifold pressure returns to the local barometric pressure. As mentioned in item 2 above, heat vaporization is more 'permanent'. In that once the fuel is heated to the point of vaporization it stays vaporized.

Diesel fuel is a very low 'vaporization pressure' (RVP) fuel, much lower than gasoline. The super low RVP of diesel fuel operates in the high compression ratio (CR) of a compression-ignition (aka diesel) motor.

I'm not trying to point out an exception. Only that the law-mandated increases in the vaporization pressure of liquid gasoline (done by oil refiners during the higher temperatures and higher barometric pressures of summer months to reduce fuel evaporation emissions) has less of an effect on the combustion process than a host of other factors.

Which is a good thing if you think about it, because the end user has no control over the refining process.


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Some of the atomized fuel vaporizes in the combustion chamber, some from the port surfaces. Droplet size matters.

So how is Iice Smooth coming along? If you build it, you could have a winner.

None of my questions ever seem to get a real response but I will try again. Hope springs eternal. Anyway...

On the throttle by wire comments poolside made a while ago... You mention that the new LC gs is throttle by wire and mention it masks poor response by not letting it happen... Lets distinguish between throttle grip and actual throttle bodies. Does this masking imply the speed at which one can move the grip is somehow governed or is the throttling done within the electronics? If just in the electronics I see no real world throttle grip response to remain unchanged. Rider experience does not change right?

Speaking purely from a physics perspective... taking into consideration cable friction and electric mechanism to fire the injectors and ignoring any "throttling" of the throttle... which solution is faster in getting the message from hand grip to fuel in the chamber?

Uh would you mind asking your question in another way?

I'm not really sure what you're trying to get at.

JJ

I get that a lot.... lol. My brain has random access gears. The problem with Addarall is you have to remember to take it...


I am saying I don't see how ride by wire masks poor throttle response unless it prevents the actual handgrip from being turned faster than the engine will respond. Does a ride by wire bike actually prevent you from turning the handle too fast or does it ignore it when you turn it to fast? If it ignores it when you turn to fast that does not seem to me to change the riders perception of responsiveness as poolside suggested the new LC boxer might do.

Are you mechanically limited in turning the grip too fast? If so is resistance on a curve through the power band? If not how does ride by mask poor throttle response from an ergonomic perspective.


Again... I took his post on it to be speaking from a actual throttle perspective. I am interested in what that masking means to the riders twist of the grip, how does the expeirence of twisting the grip and the response of the bike change? sounds like the rider experience would actually not change at all... lag still experienced the same from a ergonomic perspective. I could not care less if the lag is in the electronics that fire the injector or the electronics that pull the throttle body lever because my experience as a rider would not change would it?

I see ride by wire as an implementation detail without real rider control advantage. Why would a rider care which is used if the experience is the same?

I'll take a shot at this...

With a cable throttle when you open/close the throttle the FI system has to respond to the position of the throttle body butterfly (thru the throttle position sensor input) AFTER you have moved the throttle. IOW, you control the air into the engine and the FI processor controls the fuel to match.

With TBW, the FI computer knows what you WANT to do when you move the grip. It uses that information to move the butterfly via a motor. Difference being, the FI processor can control all of the other FI parameters in conjunction with, or even in advance of, the butterfly movement.

The response lag should be imperceptible to you in a well designed system. But the ability of the FI processor to now control all aspects of the fuel AND air delivery system means lower emissions and potentially better driveability.

TBW also lets the ECU programmer change the relationship between the twist grip and the throttle plate. 10% on the grip might be 5% at the plate if they're trying to smooth out off idle power. This lets the engine designer give you nice linear power very easily, without making as many compromises in engine tuning that reduce power. On some newer car ECUs there's a sophisiticated map for the relationship between the throttle pedal sensor and the throttle body plate. If you have the right tuning software you can modify this yourself. That's a lot easier than going into the machine shop and making a new throttle cam.

In the cases where the owner has the ability to access the tuning, electronic controls are far superior to old mechanical ones when it comes to home tuing. I'd rather adjust the ECU with a laptop than replace jets, slides and needles in a rack of carbs.

Funny, but fewer electronics, yes I know that is quickly becoming pure fantasy, sure makes for less gremlins and electron vagrancy! Old fart like me prefers stuff I can fix in BFE without batteries, solar power or satellites with just hand tools and ingenuity.

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The masking refers to masking poor emission related behavior from the engine and what the efi s/w has to do to meet emissions standards in ALL cases of engine response and performance.

With the introduction of TBW the efi can better match (less masking) the proper fuel/air delivery in all operating conditions with fewer emissions related poor engine responsiveness characteristics.

In terms of rider experience the difference is an extremely slight delay in throttle response, so slight that it's not really noticeable.

JJ

Another relative way to say that is when it's nearly too hot or to cold to be out riding. I'm not trying to be obtuse, merely hoping to lower the perceived importance of the settings. The 'really hot' and really cold' settings do make a difference, try them and see. There is no risk in trying the different settings. No risk to the bike in any way. It might be that you like one setting over another.

As JJ says, many riders like to experiment with the different settings regardless of the outside temperature. According to their reports, a few riders prefer one setting over another even during pleasant temperatures, but almost everyone leaves the jumper at the -20°C factory setting.

A more fundamental reason for the jumper settings is to maintain compatibility with the future IICE products.

-20°C is the factory setting.



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The IICE Air (with -20 setting) noticeably helped throttle response (controllability) in lower revs and reduced the amount of backfiring/popping. There is still some backfiring/popping so I'll try different settings and with/without the spark arrestor over time to see what I like best. Overall a noticeable improvement! It was easy to install too!

Bike: 2008 R1200GS with Akrapovic slip-on muffler

I posted this in my local riding thread already but I wanted to post it here as well

So I got mine just before the holidays... a great present but family obligations meant I had to wait to try it out.

That thing literally transformed my bike. Just got it installed last night. As I left the driveway the bike was still cold and I thought I probably waited four months for a modest improvement. Within a few miles I was like... holy $!#&! It was as if a ten minute install had been me finding a hidden "make my bike run like crap" switch in the on position and had turned it off. All day I been thinking why the hell did they not make the bike this way to start with? Someone asked how it affected gas mileage. First, who gives a rats ass. Second, no way to know. Why? Because the damn low gears now actually have response like low gears and I found myself actually bothering to use them all day. So I have no way of comparing milage because my riding style completely changed today.

Seriously it is the weirdest thing... you turn the handle on the right hand side of the handlebar and the bike actually moves forward when you do it! Who came up with this crazy idea? Poolside did. He is the man!

I've had an interesting experience. Right after I got my bike ('97 1100GS) I bought a Leo Vince exhaust and have ridden that way since. I also did a jumper in place of the CCP, 30-87a.

When I got my IICE Air, I didn't notice a huge improvement. A bit smoother off idle and low throttle, but that's it. I also noticed my mileage was shite.

Yesterday I put the stock exhaust back on to see if it would help the mileage. I have no clue whether it will help the mileage, but DAY-UM!! The bike is now soooo much smoother and has a LOT more low end power. :eek1 :eek1 I was really surprised.

I set the IICE back to the "zero" setting and it felt fine, but lost a bit of pep. Put it back to -20 and it's got ZIP again.

I was really surprised by the improvement going back to the stock pipe made, but even more impressed by the amount of difference the IICE makes with the stock pipe.

How long did you leave the Iceair on with the aftermarket pipe? I wonder if the ecu needed more time to adjust itself with the two together?

I have a akrapovic slip on on my 07 1200 and the difference was substantial. It may be your older electronics can't adjust for the pipe and you need a power commander to tune things manually for the pipe?

It was on with the Leo Vince pipe for about 8 months, maybe more. Frankly, I never felt my bike did well with the Leo Vince pipe. I've only done a few miles with the stock exhaust back on, we'll see how it goes over the next couple of weeks.