Jetting Baseline Help

[RivSide250r]

Going to start tuning the carb but need a baseline to start with. I ran this in Oregon last month (which is sea level) and it seemed to lag through 1/2 throttle and then took off after that. Hard to tell with just a quarter turn twist throttle on it. What you say?
It's an 86, stock stroke, 310 pro x top end with a 38 pwk a/s running 110. The current set up is
DGH needle 4th clip from top (when someone says 4th clip, do they mean from the top or bottom?)
172 main
48 pilot

Thanks for the help.

[The norm]

My 310 is set up with a 38 airstriker carb. I have a 50 pilot, 185 main, dgh needle at the middle groove, air screw 1.5 turns out. Mine is dune ported by Hybrid Engineering and a +4 mil stroke.  I ride it only at the Oregon dunes

[2ndmoto]

I think you are light on the pilot. I'd start at a 52. Tune your pilot in first, then needle, then main

[havinnoj]

300 PRO-X - 38A/S - 52 pilot, 185 main, DDJ needle (2nd from top).

300 PRO-X PV - 39PWK - 52 pilot, 180 main, DGH needle (2nd from top).

Sea level. Race gas C12 w/R50 @ 40:1.

[havinnoj]

DGH needle 4th clip from top (when someone says 4th clip, do they mean from the top or bottom?)

Clip position = top is #1, bottom is #5.  Top is leanest, bottom is richest.  Note there is overlap on clip length too (for example a DGL in #4 is equal LENGTH to a DEL in #2), clip slots are 0.9mm apart and those two needles measurable length is 1.8mm different. 

Half throttle "lag" - what do you mean?  Like it's zingy no power like a 125cc bike?  Give it more fuel (richen it up). Or it breaks up and sputters in that range? (lean it out).

Mid throttle is covered by needle length (clip) in earlier throttle openings and then needle taper. 

All motors will be different - you're in the ballpark.

[RivSide250r]

DGH needle 4th clip from top (when someone says 4th clip, do they mean from the top or bottom?)

Clip position = top is #1, bottom is #5.  Top is leanest, bottom is richest.  Note there is overlap on clip length too (for example a DGL in #4 is equal LENGTH to a DEL in #2), clip slots are 0.9mm apart and those two needles measurable length is 1.8mm different. 

Half throttle "lag" - what do you mean?  Like it's zingy no power like a 125cc bike?  Give it more fuel (richen it up). Or it breaks up and sputters in that range? (lean it out).

Mid throttle is covered by needle length (clip) in earlier throttle openings and then needle taper. 

All motors will be different - you're in the ballpark.

I don't even know if it would lag, but it would be going along and then somewhere around half throttle it would take off. Seems it was getting more fuel at that point. Almost like I blipped the throttle but I didn't, just gradually increasing speed. From what I'm reading, it needs to be richer on the bottom. I did not feel a sputter. I'm glad I'm in the ballpark.

[RivSide250r]

300 PRO-X - 38A/S - 52 pilot, 185 main, DDJ needle (2nd from top).

300 PRO-X PV - 39PWK - 52 pilot, 180 main, DGH needle (2nd from top).

Sea level. Race gas C12 w/R50 @ 40:1.

Wow...your jetting is a lot richer then mine, except the needle. What's the difference between a DGH and DDJ needle? Have you ran a DGH needle in the 300 prox with 38 air stryker?

[RivSide250r]

My 310 is set up with a 38 airstriker carb. I have a 50 pilot, 185 main, dgh needle at the middle groove, air screw 1.5 turns out. Mine is dune ported by Hybrid Engineering and a +4 mil stroke.  I ride it only at the Oregon dunes

Copy..It looks like I need to fatten the bottom end up a bit. Side topic on the Oregon Dunes...I love the place. Being from So Cal, I ride a lot of Glamis but we alternate each summer between Oregon dunes and Idaho dunes. Way different riding then Glamis. But, this last July, the weather was horrible. Very cold and very windy. Does it get better in August?

[havinnoj]

300 PRO-X - 38A/S - 52 pilot, 185 main, DDJ needle (2nd from top).

300 PRO-X PV - 39PWK - 52 pilot, 180 main, DGH needle (2nd from top).

Sea level. Race gas C12 w/R50 @ 40:1.

Wow...your jetting is a lot richer then mine, except the needle. What's the difference between a DGH and DDJ needle? Have you ran a DGH needle in the 300 prox with 38 air stryker?

I probably did at some point.  There are more variables than just motor size - port work, exhaust, reeds, fuel ratio, specific gravity of the fuel itself, oil mix ratio.  These recommendations maybe gets you 80-90% of the way there, the rest is fine tuning.  DGH vs DDJ.  Taper is the same.  Length (G is longer than D) and thus G is leaner in that range.  Diameter (H is smaller than J) and thus J is richer than H because smaller diameter allows more fuel. 

[havinnoj]

DGH needle 4th clip from top (when someone says 4th clip, do they mean from the top or bottom?)

Clip position = top is #1, bottom is #5.  Top is leanest, bottom is richest.  Note there is overlap on clip length too (for example a DGL in #4 is equal LENGTH to a DEL in #2), clip slots are 0.9mm apart and those two needles measurable length is 1.8mm different. 

Half throttle "lag" - what do you mean?  Like it's zingy no power like a 125cc bike?  Give it more fuel (richen it up). Or it breaks up and sputters in that range? (lean it out).

Mid throttle is covered by needle length (clip) in earlier throttle openings and then needle taper. 

All motors will be different - you're in the ballpark.

I don't even know if it would lag, but it would be going along and then somewhere around half throttle it would take off. Seems it was getting more fuel at that point. Almost like I blipped the throttle but I didn't, just gradually increasing speed. From what I'm reading, it needs to be richer on the bottom. I did not feel a sputter. I'm glad I'm in the ballpark.

Hmmm so it’s just surging RPM on its own?

[havinnoj]

My 310 is set up with a 38 airstriker carb. I have a 50 pilot, 185 main, dgh needle at the middle groove, air screw 1.5 turns out. Mine is dune ported by Hybrid Engineering and a +4 mil stroke.  I ride it only at the Oregon dunes

Copy..It looks like I need to fatten the bottom end up a bit. Side topic on the Oregon Dunes...I love the place. Being from So Cal, I ride a lot of Glamis but we alternate each summer between Oregon dunes and Idaho dunes. Way different riding then Glamis. But, this last July, the weather was horrible. Very cold and very windy. Does it get better in August?

Usually summer months are great but like you mentioned, I rode a weekend in July that was foggy / rainy / windy.  Not ideal but it happens once in a while. August is great time to ride.  Will you be there later this week when a bunch of us come down?