Freestyle More Bpipe fine tuning questions or is it something else
- Thread starter Polish jet pilot
- Start date
- Location
- amarillo ,tx
i discovered this weekend , i was trying to get my carbs adjusted i got the bottom end just right and the topend, but it was still bogging down midrange , so i closed bottom water adjustment bout half open, top open bout a quarter, and close my jet works flow controll pro valve down a bit i have excelent throttle responce through all ranges i would still like more bottom end hit need to open top screw on head pipe more, dont think itll get too much better with my 12/20 skat prop
Polish jet pilot
4aces4aces4aces4aces4aces
- Location
- Warsaw, Poland
My intake setup:
OEM carbs with oem f/a with 1 screen removed. Jetting: 75 low, 135 high, 95 gr spring, LT carbon tech reeds + angled spacer.
By the plugs I can say the ski is not lean.
I will close the FCV a bit, and put in the plug tip inside the stinger.
I did read all instructions for everything, know the carb jetting procedure.
What else?
OEM carbs with oem f/a with 1 screen removed. Jetting: 75 low, 135 high, 95 gr spring, LT carbon tech reeds + angled spacer.
By the plugs I can say the ski is not lean.
I will close the FCV a bit, and put in the plug tip inside the stinger.
I did read all instructions for everything, know the carb jetting procedure.
What else?
Philip Clemmons
Owner, P&P Performance
- Location
- Richmond, Va
Sounds like not enough pilot. Carbon techs need a larger pilot than most others. We run 80s on our stock 701 stuff w/thw carbon techs. You can have a low speed issue that won't show on plugs.
masterblaster
X-H2
I thought that was your findings on vf3 reeds.Ive run carbon techs with smaller pilots and been ok?
Polish jet pilot
4aces4aces4aces4aces4aces
- Location
- Warsaw, Poland
I could experiment with larger low jet. Should I taper bore the oem 38's?
Can somebody explain why sometimes the low jet is huge and high jet smaller (e.g I've seen setups that run 120 low and e.g. 100 high) - this is against my logic - but they did work.
Can somebody explain why sometimes the low jet is huge and high jet smaller (e.g I've seen setups that run 120 low and e.g. 100 high) - this is against my logic - but they did work.
Philip Clemmons
Owner, P&P Performance
- Location
- Richmond, Va
Don't taper bore stock carbs! This usually causes more issues.....
Larger lows then highs is called "reverse jetting". It's usually required to address a certain issue or characteristic of some motor/carb setups. Stock carbs will not require this.
Remember that the low speed screw is basically a idle adjustment screw. After idle, it has very little effect. Low speed issues beyond idle are a combination of low jet/popoff.
Larger lows then highs is called "reverse jetting". It's usually required to address a certain issue or characteristic of some motor/carb setups. Stock carbs will not require this.
Remember that the low speed screw is basically a idle adjustment screw. After idle, it has very little effect. Low speed issues beyond idle are a combination of low jet/popoff.
Polish jet pilot
4aces4aces4aces4aces4aces
- Location
- Warsaw, Poland
Update:
I inserted the spark plug tip into the stinger (without changing anything else) - the ski seems to have better reponse, also the pisser seems to have higher pressure which is good. I will try to adjust a bit more the jetworks valve next, and then play with the bpipe screws.
Overall the ski runs quite good but I feel there is hidden potential in fine tuning of it. At the end I will need a hooker - that is quite sure.
I inserted the spark plug tip into the stinger (without changing anything else) - the ski seems to have better reponse, also the pisser seems to have higher pressure which is good. I will try to adjust a bit more the jetworks valve next, and then play with the bpipe screws.
Overall the ski runs quite good but I feel there is hidden potential in fine tuning of it. At the end I will need a hooker - that is quite sure.
masterblaster
X-H2
sounds like your right on track now
Polish jet pilot
4aces4aces4aces4aces4aces
- Location
- Warsaw, Poland
Little update:
Been riding for 3 days, used 45 liters of gas by myslef. The ski is tuned right now (at least to what I have).
oem 38mm carb boring - I talked to a builder here - he said that he bored many of those cvarbs and removed the venturis (the restric air flow). He said that taper boring should not be a problem for tuning the carbs later. I know many people here think otherwise - stll think there is too much mistery behind the oem 38's.
I opened the top screw another 1/4 turn. Got rid off the sizzling pipe (which melted my negative cable a bit) and got some better low end - but be careful - if you open it too much the repsonse becomes too soft - power drops quickly over a certain level.
Some "action" pics:
http://www.postimage.org/image.php?v=PqESEd9
http://www.postimage.org/image.php?v=PqESObJ
http://www.postimage.org/image.php?v=PqETeDi
http://www.postimage.org/image.php?v=PqETjCA
http://www.postimage.org/image.php?v=PqET78S
Been riding for 3 days, used 45 liters of gas by myslef. The ski is tuned right now (at least to what I have).
oem 38mm carb boring - I talked to a builder here - he said that he bored many of those cvarbs and removed the venturis (the restric air flow). He said that taper boring should not be a problem for tuning the carbs later. I know many people here think otherwise - stll think there is too much mistery behind the oem 38's.
I opened the top screw another 1/4 turn. Got rid off the sizzling pipe (which melted my negative cable a bit) and got some better low end - but be careful - if you open it too much the repsonse becomes too soft - power drops quickly over a certain level.
Some "action" pics:
http://www.postimage.org/image.php?v=PqESEd9
http://www.postimage.org/image.php?v=PqESObJ
http://www.postimage.org/image.php?v=PqETeDi
http://www.postimage.org/image.php?v=PqETjCA
http://www.postimage.org/image.php?v=PqET78S
Last edited:
masterblaster
X-H2
those were my findings to the letter........
Idok
F1pro
- Location
- Nations oldest muthaF+++kin city
just installed a new headpipe on a ltd 61x..........48mm carb, port matched exhaust and intake....set the pipe at 1/2 turn out on the bottom and 1/2 turn out on the top and coudnt be happier with the bottom end...no heat issues whatsoever either
masterblaster
X-H2
ever try it with just the top screw,you might be surprised