CV44 TUNING

[Admiral Akbar]

Where did you find a 250 main? or did you just use an 1/8 inch drill?    Max

[mayor]

Sorry Red, but I don't believe for a minute that the data you are presenting is "real".      furthermore, I seriously doubt that a 250main in a cv40 would show almost the same afr as a 200 main in a cv44 with the only change being the exhaust from a Caliber to a D&D.  is that to imply that the Caliber pulls more air than a D&D (despite all the evidence of the effectiveness of the D&D)? or would you be suggesting that the main acts differently in a cv44 than it does in a cv40?  my guess is there was either an error in what was recorded, or what was posted.....

[Admiral Akbar]

Sorry Red, but I don't believe for a minute that the data you are presenting is "real".      furthermore, I seriously doubt that a 250main in a cv40 would show almost the same afr as a 200 main in a cv44 with the only change being the exhaust from a Caliber to a D&D.  is that to imply that the Caliber pulls more air than a D&D (despite all the evidence of the effectiveness of the D&D)? or would you be suggesting that the main acts differently in a cv44 than it does in a cv40?  my guess is there was either an error in what was recorded, or what was posted.....

Ya know it is totally possible that Red is runnin' a 250 without problems..

Max

[mayor]

Ya know it is totally possible that Red is runnin' a 250 without problems..

in a 95" with a CV40....netting 13.5:1 afr?  sorry just not buying it.....

[FLTRI]

Ya know it is totally possible that Red is runnin' a 250 without problems..

in a 95" with a CV40....netting 13.5:1 afr?  sorry just not buying it.....

I personally have not seen where a 250 main could effectively (not grossly rich) be used in a CV40 for any build.
Normally a typical 185-195 main will provide 13.0-13.5 AFR @ WOT.
A 250 should run the AFR down to about 11.0-11.5:1 which is way too rich to make power....on gasoline.
Maybe we're talking a special gas/alky blend?
Just my $.02,
Bob

[PanHeadRed]

>Sorry Red, but I don't believe for a minute that the data you are presenting is "real".<

It's posted on HTT how could it possibly not be true?

[PanHeadRed]

Max, there was problems, if I left the enricher out to long it would kill the plugs.

Mayor, believe what you want, but that run was recorded on the Dynojet 250 what ever at Fast Lane Cycles in Chantilly Virginia with a 250 main in my CV40. The tuners name was Will, the shop was a Sport Bike shop, what I remember most about the day (other then breaking a pair of sun glasses) was the tuner got on the phone and called the owner of Devil Dog Cycles and said "you got to come over here and see this".

Fucked up sniffer? Don't know, don't care. 

I don't think Will buys that less fuel less timing thing either.

I you wish I will mail you the jet and you can measure it for your self. Maybe it's a 249.9 and not a true 250.

[PanHeadRed]

Here are the AFR's from 24 runs that day, some are 3rd gear, some 4th some 5th. They go from 200/shims to 250


[attachment removed after 60 days by system]

[FLTRI]

"potty mouth! "ed up sniffer? Don't know, don't care. 

PHR,
I would think you should care if the AFR readings are correct. The way the tuner evaluates the AFR/power is by the signal from the O2 pump/sniffer.

If this data is not right (reads lean from air getting into the OG sensing system) the tuner will make changes to get the readings to look correct.
Service a missreading pump (eliminate air entry) and the AFR rich goes rich because it no longer gets outside air into the sensing system.

Anyway the need for a 250 main in a CV40 to get AFR to 13.0-13.5 on a 95" build with your exhaust, cams, and intake just doesn't make sense.

If I were the tuner and needed to check the validity for using the 250 main, I would simply install what I had been using for those builds (185-195) and do a pull to see what the power did.
If power went up, I would know the AFR readings were bogus. If power went down I would have to accept the 250 was prolly the correct jet.
Heck, you may have a bit more power/mileage left in that build.
Bob
PS - The fact that if the enrichener is left on too long it kills the spark plugs is a good indicator the AFR is too rich without the enrichener. Remember the enrichener also adds air not just fuel, so a properly tuned engine should be able to run just fine with the enrichener out, albeit a bit rich @ low rpms, without fouling plugs. Also, you should not need the enrichener to cold start your engine?

[PanHeadRed]

>PHR,
I would think you should care if the AFR readings are correct.<

Bob, my "don't care" statement is not as it reads, I'll explain later. That carb tune was done a few years ago, I rode that bike to NOLA and back, at times on reg gas the 3rd week in July, no problems. But I took the 250 out at the end of that summer, I prefer the tune I get using my AFR meter.

That guy tuned it I rode it, it ran fine (cept for the plug thing) I also ran it for a long time with a 220 and one shim.

I used a 200 with 2 shims, a 220 with 1 shim and a 250 with no shims, they all graphed fine depending on who's graph and what an individual wants to classify or accept as an acceptable AFR.

[mayor]

my guess is the "don't care" was directed towards another fellow.     

[FLTRI]

Red,
What color are your plugs? They should be a shade off white (we no longer have leaded gas so the tan color is no longer good).
If you were to use a high powered light like the doctor uses to look in your ears, you should find a very small ring of color at the very base of the porcelain.
If you show color on the rest of the porcelain then it is rich.

As I have mentioned, unless the air bleeds have been "bored out" a 175-195 would be really close.

The fact you are using CV44-size jets in a smaller carb tends to indicate way more fuel than necessary.
Also the enrichener deal points to too rich as well.

Just for grins maybe slide a 180 main and go for a ride and see if it doesn't feel perkier and less apt to foul plugs.
Just my $.02,
Bob

[PanHeadRed]

>my guess is the "don't care" was directed towards another fellow.<     

Not at all, I was just pointing out that it was so long ago it no longer matters..........to me.

My point was here is a chart that shows a 250 slightly rich, and I can show another that shows a 200 shimmed even richer. Which sniffer is right which is wrong? Maybe there is error in both?

[PanHeadRed]

>The fact you are using CV44-size jets in a smaller carb tends to indicate way more fuel than necessary.
Also the enrichener deal points to too rich as well.<


Bob, I was but am not currently. Current set up is a 44,  50 slow - M needle - 200 main

Current WOT is high 13's SS Cruise with a 30% load is middle 14's. I liked it the Dyno guy liked it, so I don't see a 185 in my future.

The 250 in the 40 was a few years ago. I went in for free Dyno time (a couple of pulls to measure power no tunning) with a 220 and one shim. The operator offered to tune it for "free" so I let him do his thing, I left with a 250 and no shims. Rich? Yeah with the cable pulled, Death to the engine? Not hardly.

But like I said that was a few years and exhaust systems ago, I have moved on.

[FLTRI]

>The fact you are using CV44-size jets in a smaller carb tends to indicate way more fuel than necessary.
Also the enrichener deal points to too rich as well.<
Bob, I was but am not currently. Current set up is a 44,  50 slow - M needle - 200 main

Those numbers look right for the application....more air - more fuel.
The CV40 with the 250 is less air - more fuel, too much fuel.
The tune was free and you got what you paid for IMO.
Anyway glad to hear you got it right in the end,
Bob

[Admiral Akbar]

My point was here is a chart that shows a 250 slightly rich, and I can show another that shows a 200 shimmed even richer. Which sniffer is right which is wrong? Maybe there is error in both?

Come on.  You guys don't know why that motor is going way rich at WOT with a 250 main?

Max

[FLTRI]

Come on.  You guys don't know why that motor is going way rich at WOT with a 250 main?
Max

U-h-h-h, because the main jet is too big???

[Admiral Akbar]

Come on.  You guys don't know why that motor is going way rich at WOT with a 250 main?
Max

U-h-h-h, because the main jet is too big???

ooops

Come on.  You guys don't know why that motor is not going way rich at WOT with a 250 main?

Max

[Jeffd]

I had a dyno run once by a guy who built some world record horse power hybusa motors (arcane motorsports) and he was not familar with v-twins and he stuck the sniffer barely in the end of the muffler and got a lean reading no matter how big of jet we put in.  I wonder if the dyno run with the 250 main was doing the same thing?  sniffer not far enough up the pipe.

[FLTRI]

I had a dyno run once by a guy who built some world record horse power hybusa motors (arcane motorsports) and he was not familar with v-twins and he stuck the sniffer barely in the end of the muffler and got a lean reading no matter how big of jet we put in.  I wonder if the dyno run with the 250 main was doing the same thing?  sniffer not far enough up the pipe.

Possible. All I'm saying is the AFR reading isn't correct if a 250 main in a CV40 shows anything but pig rich @ WOT.
Just my $.02,
Bob

[Sonny S.]

I had a dyno run once by a guy who built some world record horse power hybusa motors (arcane motorsports) and he was not familar with v-twins and he stuck the sniffer barely in the end of the muffler and got a lean reading no matter how big of jet we put in.  I wonder if the dyno run with the 250 main was doing the same thing?  sniffer not far enough up the pipe.

Possible. All I'm saying is the AFR reading isn't correct if a 250 main in a CV40 shows anything but pig rich @ WOT.
Just my $.02,
Bob

[Admiral Akbar]

I had a dyno run once by a guy who built some world record horse power hybusa motors (arcane motorsports) and he was not familar with v-twins and he stuck the sniffer barely in the end of the muffler and got a lean reading no matter how big of jet we put in.  I wonder if the dyno run with the 250 main was doing the same thing?  sniffer not far enough up the pipe.

Possible. All I'm saying is the AFR reading isn't correct if a 250 main in a CV40 shows anything but pig rich @ WOT.
Just my $.02,
Bob

  Sure it's possible to from 220 to 250 and not have the AFR read rich..  If you don't think so then you don't understand how the CV works.. Same for all slide type carbs..

Max

[Sonny S.]

95", mild compression, low lift, short duration cams. You think that motor can move enough air through it with a CV40 to support a 250 main ?

IMHO, if a 250 main is needed then HP #'s should be very high.

but then again, I don't understand how the CV works 

[Admiral Akbar]

You think that motor can move enough air through it with a CV40 to support a 250 main

It depends on the diameter of the needle at the end.. Heck you even be able to go bigger.    Max

[PanHeadRed]

>You guys don't know why that motor is going way rich at WOT with a 250 main?<

Nope I don't, it showed 12.7 - 12.2 on the meter. That may be to rich for some schools of thought, maybe not others.

Define rich.