Flash 3.26

[bakaracer]

my mhr 72 setup with oko 24 carb is 50 pilot 118 main. so a 48 or 50 pilot.

[Wheelman-111]

Greetings:

Which pipe are you running on the MHR?

[Wheelman-111]

Greetings:

With the 48 Pilot, it acted a bit less cold-blooded this morning, but still needed a touch of choke - just for a second - the first and second time the revs got up. I think it's just leaning out when the Internal Gales meet the cold crankcases. I couldn't get down to see if it was sweating or icing up. It was warmer - 45-50-ish - so maybe the #50 Pilot is the right call for me too. If I do that, should I drop the main from 120 to 118? Or try it with the 120 first?

VDO Temp gauge locked in at around 300 with no off-throttle spike observed. Power acted as usual, pretty good.

[bakaracer]

I'm running a msp muffler type pipe. its like a pg typhoon or v8 pipe. yeah drop down to a 118 if your going to use that 50 pilot. play with the air fuel screw too.

[Wheelman-111]

Greetings:

Cold (high 20s) mornings reveal a new symptom: despite the 48 pilot and several minutes warmup the Corsa is reluctant to take mid-throttle for a mile or so.
It takes off well enough, and if I keep laying on more throttle it goes. But if I back off any and then open, it loses power and even threatens to stall.
If I get aggressive and lay on more throttle, sometimes I can get it to re-accelerate after several seconds of Bleahh.
The issue disappears as the block heats up, but it's almost dangerous to take it into traffic. It responds immediately if I reach down and lift the choke knob, but that's not too safe either.
I wondered if the #9 HIX plug was too cold and loading up. . It looks dark and moderately coated with carbon on the rim at around 400 miles. Sort oof stiff unscrewing it... Swapped in a BR8HS tonight but haven't tested.
Also wondered about carb icing - it's pretty humid too.
Jets are 48/118 or 120. Needle is K6B and clip at center.

[Bear45-70]

So try a 50 pilot and see if it is too lean.

[Wheelman-111]

Greetings:

Thanks, Bear. I'll do that and follow Bakaracer's suggestion to monkey with the air bleed screw - richen in the cold AM, lean back in the warmer PM. I'll verify the position of my jet needle too.

Here's a microscopic view of the plug after ~350 miles:

F3.2PlugJan3_2011.jpg (14.18 KiB) Viewed 4421 times

The light in a (Wheelman-grade ) photo can be tricky to interpret. The ring at the base of the threads looks charcoal black. I suspect the inside of the head looks much the same. The insulator looked dark brown on removal, but lightened a bit as the plug dried. This was removed after a brief WOT run - 1/4 mile or so, then a good minute of off-throttle coasting back to Casa Wheelman. Note the little deposits of coagulated Motul 810 around the center Irie-Dee-Yum electrode. All this suggests the #9 plug is too cold for this weather.

Another Plug shot:

F3.2PlugBigJan3_2011.jpg (26.95 KiB) Viewed 4421 times

Wheelman-grade...

[Bear45-70]

Those are pics of spark plugs. I thought they were pics from ghost hunter.

[Wheelman-111]

Greetings:

Oh, so kick a man while he's down why don'cha? Actually The Bear has a point. If you sqint your eyes a little, the globs of undigested Motul in the first pic resemble an anguished Death Mask of the missing Union Boss Jimmy Hoffa.
If you don't see it, try a couple glasses of cheap Merlot first.

OK so I put the 50 back in along with a #8 plug and swapped the main down to 118. I may be onto something. There was still an early throttle lag but only for a quarter-mile and much less severe. It was easier to "catch" by rolling on more throttle. No need for choke at all.

It was weird to see the temp gauge make a little jump Down, not up, when I cut the throttle. WOT still peaked below 350 and the pull was palpably stronger. 62.8 MPH registered in less than a quarter-mile despite added drag of a replacement toilet seat box pinned by my feet to the leg shield.

The only fly in the ointment was a mild mid-throttle case of 4-stroking, probably due to raising the jet needle up a click to middle position, making the mixture briefly too rich at half- throttle. Easily remedied by dropping the needle a click leaner.
Maybe install the next thicker (leaner) needle? Now have K6B.

[bakaracer]

try it with the clip 1 up from middle and play with the air fuel screw. if you go with the thicker needle,you will lean out another section or sections.keep in mind that the clip doesnt have to really be in the middle position. so wheel looks like your at the jet setting I suggested.

[Wheelman-111]

Greetings:

Yes, O Wise Baka-san: 50/118 as you foresaw. Y'know that worries me a bit. We're running different pipes and bores, so maybe one of us is off.
Were it not for the thunderstorm here in Deepinnaharta, I believe I could better my to-date top speed of 65.8.

[bakaracer]

sometimes the air quality can cause that. once the air temps come back up,you will be changing jets again.at the track i'm adjusting my settings all the time due to air quality even to the point that i'm switching airfilters to get it right.

[Bear45-70]

sometimes the air quality can cause that. once the air temps come back up,you will be changing jets again.at the track i'm adjusting my settings all the time due to air quality even to the point that i'm switching airfilters to get it right.

baka, when at the track do you have a portable weather station or do you use experience and good judgement?

[bakaracer]

its by experience but I check the weather on my phone to confirm what I'm adjusting by seeing what the air temp is, humidity and berometric pressure is.sometimes the trans can mimic some carb adjustments a little.

[Wheelman-111]

Greetings:

I think I know what you mean, Baka. Back when I was tuning the OKO24, the combination of springs and weights caused my Giant vario to shift sort of suddenly just at an RPM where there was a midrange engine flat spot in power. The combination resulted in a non-linear acceleration issue in the midrange unless I really got on the throttle. A little (2-gram) decrease in the Vario load solved the issue. I'll move my needle down a click and see if I have attained Nirvana.