Carb and Mileage

[jerrymac]

I have had the carbs rebuilt by a reputable carb shop that works on Gold Wings and Valks and drove for a few 100 miles and took it to a alk mechanic in shawnee at a Honda Dealer and tweeked it.It improved a bit,ibut is still running rich and pipes are black,he pulled caps off and dumped aftermarket jets in his palm,the spacers looked to be in the middle,any advice will help. :crazy2:I'm getting 23 to 26 MPG

[shortleg]

  Are you talking about needles with shims or an aftermarket
needle kit.
  The jets are in the bottom of the carbs.
        Shortleg[Dave]

[jerrymac]

needles under the diaphram

[sandy]

If they're Dyna Jet needles, they should be on the second notch down from the top. I get 37+ MPG when set there. Runs good too.

[98valk]

dyna jets needles are the richest needles, then factorypro, then OEM.
factorypro with the proper pilot jets and the front two carbs one clip richer than the other four will be the best setup. for MPG use the OEM with the front two one shim extra

[Ricky-D]

I know I've read that (shim the two front carburetor needles) in some past threads and I kinda remember reading something about the same deal from an aftermarket needle/jet mfr., whether it was here on the forum or from the mfr. web site I don't remember.

My primary question about this particular practice is: What does it accomplish?

It seems to me that the affect of the change would be unnoticeable since the change is minimal.

Have tests on a dyno proved out the needs for this particular change and if so: Why not all six carburetors?

I feel that the only true effect from this little change might be a blip in the gas mileage to a small extent.

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[BudMan]

I think the problem is simply too much fuel at all operating ranges.  The pipes are bluing a lot, and quickly too.  I suspect the after market needles in the carbs are too small in diameter for whatever particular jet is in the main.  I know people will re jet and re needle for specific pipes, but as I only run stock pipes, I can't offer an opinion on what is required for his Cobras.
What jets and needles do some of you guys run that have Cobras on a Standard?  I think his is a 2003. Right Jerry?

[98valk]

I know I've read that (shim the two front carburetor needles) in some past threads and I kinda remember reading something about the same deal from an aftermarket needle/jet mfr., whether it was here on the forum or from the mfr. web site I don't remember.

My primary question about this particular practice is: What does it accomplish?

It seems to me that the affect of the change would be unnoticeable since the change is minimal.

Have tests on a dyno proved out the needs for this particular change and if so: Why not all six carburetors?

I feel that the only true effect from this little change might be a blip in the gas mileage to a small extent.

***

factorypro.com did the dyno work. my understanding it is due to airflow in the airbox. With my airbox mods it was even more noticeable, that being a slight leaness when opening the throttle. IMO it is due to how the front carb bowls are filled from the middle carbs. they do not get fuel directly from the tank. FP goes into detail about how important fuel bowl level is to the correct operation of the bike.

[Ricky-D]

CA writes:

FP goes into detail about how important fuel bowl level is to the correct operation of the bike.

I strongly agree with that concept.

I think a little bit of my gurgling is that exact issue. Namely, a too low float bowl level in a couple of carbs.

Seeing that the floats and the needles are a non-adjustable item in the Valkyrie carbs I just live with the results although I hate it!

***

[GOOSE]

jerrymac.....my 2000c-t with cobra pipes......stock needles/105 mains/ 38 slows/ interstate icm/ 6-degree wheel/ fuel/air screws out 1 1/2 tuns from stop = 42 mpg

[jerrymac]

2003 is right and the pipes are blueing fast

[98valk]

2003 is right and the pipes are blueing fast

too reasons pipes will blue excessively, 1) most common is leaness, 2) too rich, whereas raw fuel is exiting into the exhaust pipe and igniting

[Ricky-D]

With single wall exhaust pipes, as opposed to the stock pipes which are double wall, bluing is a fact of life.

***