Freestyle jetting for single 49mm full spec

[waterfreak]

anybody got experience with this set up ? what was your starting point and was a restrictor in the return used?

it's going on a 61x big bore with enhanser and b-pipe

 

[Polish jet pilot]

I'd go around 140 low, 170 high, 2.5 N/S and 95 gr spring...

 

[waterfreak]

I'd go around 140 low, 170 high, 2.5 N/S and 95 gr spring...

do you have the same set up? who gave you this info?

 

[GIL]

anybody got experience with this set up ? what was your starting point and was a restrictor in the return used?

it's going on a 61x big bore with enhanser and b-pipe

The smart move is to ditch the Full SPec and go with Black Jacks! 130/130/2.0/95grams unless MS109 and then go to 80grams

 

[waterfreak]

The smart move is to ditch the Full SPec and go with Black Jacks! 130/130/2.0/95grams unless MS109 and then go to 80grams

well!... maybe I aint that smart cause I'm gonna stick with this unless it doesn't work out

BTW, should'nt you be in some other threat figuring out how to roll or something lol

 

[GIL]

well!... maybe I aint that smart cause I'm gonna stick with this unless it doesn't work out

BTW, should'nt you be in some other threat figuring out how to roll or something lol

I have decided barrell rolls are for losers. (and old men). LOL jk Say HI to Charlie!!!

 

[sjetrider]

I ran this setup on a ported 760 with b-pipe, enhancer and lightend flywheel. Had some success at 2.0 n/s 80g spring 140p and 165m. Better succes with dual 46 mikunis though. Had the singl doing good but not great. Good news its easy and quick to change jets cuz I did alot of it before it worked good.

 

[waterfreak]

I ran this setup on a ported 760 with b-pipe, enhancer and lightend flywheel. Had some success at 2.0 n/s 80g spring 140p and 165m. Better succes with dual 46 mikunis though. Had the singl doing good but not great. Good news its easy and quick to change jets cuz I did alot of it before it worked good.

cool...thanks for the info. Did you use a restrictor in the return line?
what was your low/high settings?

 

[sjetrider]

yes a 60 in the return and i always jet till I am half out on bottom and one out on top.

 

[SUPERTUNE]

Yes, you need to have big jets in order for singles to work.
Use #60 for return jet if the carb body stock return is drilled out.
I needed to use even bigger jets than posted and lower pop-off with a Novi big bell 48mm (not the FS 48) on a 862cc 8mm XS stroker

 

[Idok]

I know the 49 full spec on my scream motor runs a 160 pilot, Chuck gave me the jetting on it once......but I dont know what happend to it

 

[DangerBoy]

I ran this setup on a ported 760 with b-pipe, enhancer and lightend flywheel. Had some success at 2.0 n/s 80g spring 140p and 165m. Better succes with dual 46 mikunis though. Had the singl doing good but not great. Good news its easy and quick to change jets cuz I did alot of it before it worked good.

same mtr and story here with a 48 novi and Ive been tearing my hair out trying to get it to run off the bottom.


The carb came " jetted for a big bore" and had 125 pilot and 135 main 2.0 and 21 psi pop off

Im now at 160 pilot 140 main 2.5 and 13 psi pop off and now its starting to run right:banghead:

 

[waterfreak]

same mtr and story here with a 48 novi and Ive been tearing my hair out trying to get it to run off the bottom.


The carb came " jetted for a big bore" and had 125 pilot and 135 main 2.0 and 21 psi pop off

Im now at 160 pilot 140 main 2.5 and 13 psi pop off and now its starting to run right:banghead:

did you have the bell top or OEM . The jetting you posted would be for an OEM top style 48 novi

 

[sjetrider]

I have found that the Novi's always seemed to need lower pop off IE bigger n/s than the FS. I couldnt believe how hight the jetting ended up on the FS and honestly it prolly would have taken a higher pilot. I got sick of drilling it bigger and bigger and bigger. I think i actually ended up at 145p and 165m and I have always used 1.8 or 2.0 n/s in Full Specs. Seems to get better response on bottom this way.

 

[waterfreak]

same mtr and story here with a 48 novi and Ive been tearing my hair out trying to get it to run off the bottom.


The carb came " jetted for a big bore" and had 125 pilot and 135 main 2.0 and 21 psi pop off

Im now at 160 pilot 140 main 2.5 and 13 psi pop off and now its starting to run right:banghead:

did you have the bell top or OEM . The jetting you posted would be for an OEM top freestyle style 48 novi

 

[oxnard111]

same mtr and story here with a 48 novi and Ive been tearing my hair out trying to get it to run off the bottom.


The carb came " jetted for a big bore" and had 125 pilot and 135 main 2.0 and 21 psi pop off

Im now at 160 pilot 140 main 2.5 and 13 psi pop off and now its starting to run right:banghead:

What hair??? haha. I kid I kid.

 

[waxhead]

What intake manifold are you using. I see alot of people using the 650 kawi manifold and this becomes the limiter in the flow. The end result is that it reduces the signal seen at the carb. Which requires the big jets. If you want a single carb to work( god know why you would want to) then have a good looki at the intake and make sure its flowing enough and if not then port it to try and pick the flow up. This will make it alot easier to jet. Every time you get the flow up to the flow of the carb you are going to make it easier to jet. This is why the atp manifolds worked better they flowed more than the 650 kawi manifold

 

[masterblaster]

must really be substantially less flow if total jetting was 310 and still could of used more. it is strange how the fs carbs need the smaller n&s and higher popoff to really rip,although jetting is close to other types of carbs in the same size