Mik 48 tuning

[fuzznut5197]

Great story Bob. I would venture to guess that the T-jet on the Mik was a substantial contributor to the fuel needs at 60ft, and a fuel disruption from the T-jet would make it go lean. Perhaps the fuel feed for the T-jet was not in the ideal location in the bowl, and the acceleration would push the fuel back, exposing the feed to air?

[FLTRI]

"Hint2: It is pointed out in your pics."....and your notes.
I don't want you to get agitated with this, so if you don't want to guess anymore let me know.
Bob
Just through in the t-jet, well I don't know why. Maybe cause it's winter?

[fuzznut5197]

Agitated, me? 

Haha, just kidding, and it's funner if someone guesses, so don't spill the beans!

Your turn, Max 

[Admiral Akbar]

Bowel gasket acts as a baffle? I already said that... Max.

[FLTRI]

"Bowel gasket acts as a baffle?" I would assume slosh-over would create rich, rather than lean AFR?
Nope, but there are great clues in Fuzz's pics and text and statements Fuzz made about the differences between the 2 carb.

Think about my statement regarding 60ft events.
Keep guessing!

[fuzznut5197]

I edited the float needle tab portion of my post. 

Bob, does it have something to do with the rear float thinking the gas level is artificially high, shutting of the gas?

[FLTRI]

I edited the float needle tab portion of my post. 

Bob, does it have something to do with the rear float thinking the gas level is artificially high, shutting of the gas?

Yep, the G-force @ launch forces the fuel to the rear causing the float to shut off the fuel. Then, after 30ft the G-force wanes allowing the float to come back down and refill the bowl......too late.
Also the S&S carb has a problen with the perpendicular float getting loaded to the rear causing friction and keeps the float from "swinging" free, just doesn't shut off the fuel as with the Mik.
Just another value to EFI.  This bike is of course with a slick tire so it launches hard.
Have a Happy New Year!
Bob
PS - Take a gander at my post in Dyno Runs about the "Singh Grooves" and let me know what you think. 

[fuzznut5197]

Yay! What did I win? A S&S VFI kit? Thanks!!!!!! 

[FLTRI]

"Yay! What did I win? A S&S VFI kit? Thanks!!!!!!"
Oh shoot! Sorry you wanted that instead of the S&S124crate motor that was donated for the winner. Thanks!!! Guess I'll take it for my bike!!!

[fuzznut5197]

"Yay! What did I win? A S&S VFI kit? Thanks!!!!!!"
Oh shoot! Sorry you wanted that instead of the S&S124crate motor that was donated for the winner. Thanks!!! Guess I'll take it for my bike!!!

Rats!!!   

[Admiral Akbar]

Well, I wouldn't have figured that one out.. Max.

[FLTRI]

Max,
When I first got into data acquisition as applied to racing vehicles, and instrumentation of racing vehicles in the late 80's, there was a whole new vista opened to race teams, engineers and mechanics. For the first time, extensive engine, chassis, and aero data became available that before, was only available to a very elite few (ie: Formula1, etc).

It was a struggle in the beginning due to assumptions of what was happening inside engines that had been "gospel" from day one. So when engineers, mechanics, etc first saw conflicting info, from actual recordings of events and measurements they simply didn't want to believe the data. Had to be bad data.

However that was a lo-o-o-o-o-ng time ago. Since then d/a systems have become as necessary as tire pressure gauges. Virtually all forms of motorsports rely on data now rather than SOP for their information. (except where outlawed - then testing days are used to gather the data)

Sorry for the extraneous info but I live and breathe finding improvements, even now that I am semi-retired, tuning EFI (and carbs) which is a great deal, especially when the customer comes back from his test ride after the tune, with a SH$T eatin' grin on his face.

Happy New Year Max,
Bob

[hrdtail78]

Thanks for everybody that thought and tried to give me input.  Really enjoyed the pics and the break down of the 2 carbs Fuzznut.

Now the solution to my problem.  My shift light was set at 5600.  Turned it up to 8000 and problem went away.  Wish I would of done this first of course.  Threw in a set of points, made my carb more rigid, and swung a dead cat over my head under a full moon.  This isn't the final tune of course.  I am thinking of changing cams to the S&S 600 or back to the RR620.  I think it could use more exhaust duration than the S&S585V that is in it. 

Anybody want to show me how to take a run file out of winpep and look at them normal.

Thanks again.

[attachment removed after 60 days by system]

[FLTRI]

"and look at them normal" HUH?

[hrdtail78]

How I posted the file is as far as I can go.  You need winpep to view it.   How can I post it, and other can read it with out winpep.

[fuzznut5197]

How I posted the file is as far as I can go.  You need winpep to view it.   How can I post it, and other can read it with out winpep.

You need to turn the graphs in winpep to an image file:

In Winpep-

File --> Export Graph

Make a name and save it as a JPG.

[hrdtail78]

Thanks Fuzznut.  Got it.