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Coolant temp: 150-160. Pilot jet 40: a hair above 2.5 turns out on air screw the idle is still rising. Going to drop that down. In 4th gear and beyond wacking the throttle 1/4 to 3/4 boggy/flat response, becomes more apparent in the higher gears. CEK needle middle groove. I’m going to work off this. Plan is to test the 38 pilot jet, and the CEK on the 4th groove from top. I’ll keep this updated. I’m trying the best I can with the time and energy I have after work. Thanks to all who are following this.

I did ask Ron Black about this and for what it’s worth he said: “I’m not sure on what to tell you, I have heard of the same issues with others that have ported cylinders….. You should contact frp about your tuning issues.

Thank you, Ron”

Try this with the air screw....find the spot where you can give it quick rev in neutral and the idle hangs high. Then turn it in an 1/8 turn, give it a few seconds and rev it again.
For instance at 2 turns out it hangs, at 1 3/4 it returns to idle well. The sweet spot of throttle response is going to be right around there. In my opinion that's the number of turns you want to take note of. If that's between 1 and 2.5 you're good. I haven't had the best of luck just turning it and trying to find the highest possible idle. I like to find where the rev hangs and go from there.

All this with the engine all the way up at operating temp, preferably even blasting a few quick rips, not just cold then brought up to temp by sitting there and idling.

Make sure you don't have your idle set too high. If it is it can cause weird issues with trying to set the air screw.

I will try your suggestions next time I get out there. Compression test 167 psi. I did toss the airbox lid and will tune with it off from here on. If I can’t get it right within the next month I’m going to source a stock cylinder. SS109 I did set the float height to 18mm btw.

Was never able to even get to the plug chop of the jetting guide. I ended up with a 38 pilot, tried the dek needle 2nd 3rd, and fourth groove. Never any improvement. This engine will not pull off idle. If I’m in second and just barely moving, I’m talking right off idle, and stab the throttle the power is flat and weak from 0-1/3 throttle. Past 1/3 throttle it comes alive but nothing to brag about, ,not how it should be. It seems like the porting simply moved the torque curve above idle. I know in standard form the bike made all the torque down low. I am giving up and looking for a stock cylinder. Thanks for the help all of you.

Just curious... are you sure the KIPS valves are working and timed correctly?

SS109 wrote: ↑10:34 pm May 29 2023 Just curious... are you sure the KIPS valves are working and timed correctly?

Absolutely they are timed perfectly.

Try some VP vpr & some Amsoil 50:1. I know both are expensive but try some.
https://vpracingfuels.com/product/vpr/?c=220&

I appear to have the same mods you do. The bike may not need this kind of fuel, but it damn sure likes it.
I've never run pump gas though mine after mods, so I can't speak to that.
Just throwing out my 2 cents.

Molly's 70 wrote: ↑06:11 pm May 30 2023 Try some VP vpr & some Amsoil 50:1. I know both are expensive but try some.
https://vpracingfuels.com/product/vpr/?c=220&

I appear to have the same mods you do. The bike may not need this kind of fuel, but it damn sure likes it.
I've never run pump gas though mine after mods, so I can't speak to that.
Just throwing out my 2 cents.

I may give that a shot. But If it did help wouldn’t be willing to spend the type of money for fuel over time.

I tried the oem cylinder head today. No difference except for alittle less snap. Let me get one more thing straight, you guys can roll along in 2nd like 5mph barely moving wack the throttle and light up the rear tire? But the plan is to return to basically a stock baseline. Stock pipe, stock porting, but I will however run the RB head and carb.

5 mph in 2nd is on the verge of stalling. It should lug from there with no issues, not rip though.
5 mph in 1st would have instant spin or wheelie if I punched it.

My buddy has a KTM 300 and that’s not lighting up a rear tire in 2nd gear at 5 mph.

Both bikes engine tones would say “you’re in the wrong gear for all that”

The stock pipe is trash. The powerband is over just when it wants to "get on the pipe".
I rarely just wack the throttle. However, in 2nd gear just putting around and I open the throttle it will GO!
No hesitation & shift to 3rd quick.

Have you contacted Jeff Fredette for advice yet?

Molly's 70 wrote: ↑11:20 am Jun 02 2023 The stock pipe is trash. The powerband is over just when it wants to "get on the pipe".
I rarely just wack the throttle. However, in 2nd gear just putting around and I open the throttle it will GO!
No hesitation & shift to 3rd quick.

Have you contacted Jeff Fredette for advice yet?

Yes I have. I’m beginning to think that maybe I am just expecting too much out of the bike.