LO206 main jet tech question

Freezeman said:
I don't have one Mac_49 yet I think there is a tech tool that checks the needles length and tapper.
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I'd be interested to see if the results are the same as the jets in that, technically, some might not even pass their own tech specs if oblong.
I see a market for those that sell the best flowing jets and thinnest "legal" needles for a higher price lol.
Kinda like back in the flatty days, there were certain stamped carbs that were better than other counterparts yet still legal. And they went for more. 🤷‍♂️
 
Michael Curry said:
You could do like several people are doing now.

Order blank jets B&S 555639 (5 pack) and drill to desired size.

Then laser the proper "95" on the side.

I personally don't do this, as that is just way too much effort, for so little gain.
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People’s creativeness never ceases to amaze me. They need to spend more time at the track and less time thinking up these things!
 
SteveNoCo said:
I'm looking to get back into karting next year and I'm doing some research.

I live in Colorado and I know that some have said that there is I can find a smaller jet for the altitude. The rules say "0.036 go, 0.039 no go". With out buying a whole tech kit I just want to buy a few pin gauges to find a legal jet. So the 0.036 is that the size of the pin gauge or the size on the hole in the jet? So I guess I'm really asking do I need an 0.036 pin gauge or a 0.035 pin gauge to check for an 0.036 jet size?
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As you can see from the illustration, .0365 is number. .039 is a high number. That's 14.25% between them. That's 14.25 points on the air density gauge. Now if you need more than .039, or less than .0365, you can adjust the float level. Here in Austin Texas, 14.25% air density is about the limit of change we have in a year. I have 2 1/2 years of charts to prove that.
 

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Derek wrote:
People’s creativeness never ceases to amaze me. They need to spend more time at the track and less time thinking up these things!
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It is starting to remind me of the old Flathead days :rolleyes:

A few weeks ago at the track, Ryan Cassity gave my son some driving advice that ended up netting him two heat wins in a row.

The next weekend we were testing for a move to another class...…..
He then gave him a chassis tuning suggestion that knocked .2 off his best lap time of the day. Then his Dad came over while I was making a gear change, took the gear away from me that I was getting ready to put on, grabbed one that was three teeth the other direction from where I was going, and that resulted in a .4 reduction.

Shaking my head sometimes at even what I do :ROFLMAO:

I worry about keeping my carb clean, not what my jet measures......that is for Bob, Tom, or Steve to worry about :cool:
 
I haven't found a 206 carb yet that I couldn't tune properly with the needle and float without messing with illegality of the jet.
For each clip on the BGB needle is worth approx. .001" in main jet size. Why all the effort to break the rules on the jet?
There is definitely a difference in main jet sizes from the factory though, no doubt. That's why you get one carb that tunes nicely on the second clip, and another that works best on the third clip. Stands to reason...or you could go through all the effort that Mike is talking about I guess...seems to accomplish the same thing but is illegal if caught.
No doubt spending a little more time behind the wheel or spinning some wrenches on the chassis will make up more time than fiddling with aftermarket main jets, but I don't doubt there's someone doing it -- just like the 1HP head being discussed in another thread on here...people will buy just about anything that they "think" will make them faster.
 
Actually, stamping or etching was waived in 2019. The reason, hard to find someone non-compliant because the etching was light, or the tech guy has poor eyes!
 
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