..it's a labor of love..

[wordslinger]

...wow..it's been one major task (labor of love?)...but i've finally hit the setup, i think...

..and i gotta give thanks to my bud zombie, for clearing my jumbled-up head, and leading me onto the path of righteousness...
..for this was for me, a quest of biblical proportions...

..even tho my blown air 1.0 setup was an unexpected success, i wasn't really satisfied due to the fact that i just knew i could get more exhaust outta the cylinder. Since i was forcing more fuel mix into it, it seemed to be the next logical step....
..i cut my muffler open, removed the catalytic converter and about 1/4 or so, of the internal baffle...
..this had positive results, but my scoot would backfire at idle, when i tweaked the throttle...
..a 1.02 mm diameter jet seemed to be about right, but i couldn't get rid of that backfiring condition...
..so I drilled my slow jet to .020" , and that was wwaaay too big, because i had to close my idle screw completely off to even get a halfway decent idle, with the idle speed screw run all the way in...but the idle backfire went away....
..however, then i would get a backfire nearly every time i decellerated from a full throttle run...
..so, i added a cpl more washers beneath my needle, thinking that it was too low, cutting off the fuel supply when i dropped the throttle back quickly...well, this kinda helped, but i had a major lag during acceleration that was just not acceptable...embarassing even....what i didn't account for was the added weight of the washers......
..about this time was when i picked zombie's brain..again...he told me to increase the main jet, and drop the needle...which i did...several times...until i finally hit on my current, and pretty much satisfying setup...

..so marinate on these specs if you will, for a 2008 49.5cc 4 stroke gy6 139QMB engine with 44,800+ km on the odometer....

1.08 mm diameter main jet (108 jet in some worlds)
.5mm diameter slow jet (too big but ready for a performance exhaust upgrade)
idle screw open only 1/16 turn (see above)
needle raised .050" (from .025")
and i removed the spring from the top of my carb's slider...(radical, huh?)


..dang....wish i had found this forum when my scoot was new.....

[Shaka]

Sounds like you've been busy!!!  Any further increase in performance?  What are your plans for a new exhaust? 

[zombie]

I also have my idle screw barely cracked open. (about 3/4 turn) I could go smaller on the pilot but found there is more control w/ this set up. I'm not so sure about running NO spring tho. Just be ready to turn the key to OFT. Back fire is pretty normal for a 4t that is running on the performance edge.(De-accell only) Sucks to explode mufflers tho...

[wordslinger]

Sounds like you've been busy!!!  Any further increase in performance?  What are your plans for a new exhaust? 

..yeah, acceleration picked up a bit, and i'm able to maintain speeds a bit better...

..it seems that once i get up to any particular speed, the scoot will not fall off as bad when i hit inclines...

..i don't even wanna talk about top speeds until i can gps it, as i think my speedometer will register no further..

..i'm not sure aboiut what exhaust..i'd like something that's gonna open up acceleration, and pretty much do what these mods have done..just help me maintain higher low speeds...

[wordslinger]

I also have my idle screw barely cracked open. (about 3/4 turn) I could go smaller on the pilot but found there is more control w/ this set up. I'm not so sure about running NO spring tho. Just be ready to turn the key to OFT. Back fire is pretty normal for a 4t that is running on the performance edge.(De-accell only) Sucks to explode mufflers tho...

..it's funny you should say all that, because last night i drpped the nedle back to stock position, put the spring back in and drilled to a 1.09mm jet...

..and i also read an article that said the same thing about decel backfiring...

..actually once i got the idle mix dialed in, i hardly get the backfire at all...

..and by "dialed-in" i'm talking about making miniscule adjustments to the screw...

..like turning a 32nd of a revolution or less....

[zombie]

Well slinger You know I hate to throw money at things, so I'll leave it to you to throw some!   http://www.scootertronics.com/kecagy650fos.html   This carb has an acell pump to get rid of the bog, and is 3-4 times better than what you are running. I think it would be the best buck fitty spent.

[wordslinger]

...well, increasing the jet, and dropping the needle back to stock took care of the bog, and i actually gained some accelleration speed...

..however... 20mm.....

...i like the looks of that...

...20mm....hmmmm...............

 

[Shaka]

Slinger, doesn't the stock carb have an accelerator pump?  I thought yours did.

[wordslinger]

..yes it does...

..but itsa 19mm....that 20 sound niiice....

[zombie]

I'm running a 28mm. I just love sucking up ALL the air around the scoot. The local Cops think it was just a noisy heat wave that passed them. On the real tho. The extra air flow will eliminate the "tweakieness" all you AG/50's seem to suffer.

[wordslinger]

..well, for the time being, i'm done with mods...imma just ride and enjoy for a while....

 

[zombie]

Happy Trails my man... Here, kitty kitty kitty!    Naw, I like mine the way it is too!

[wordslinger]

...however an over-range variator would be instant top speed....hmmmm...