Pwk jetting question

Could we get a picture of your setup?
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pay no mind to the air filter, I didn't have the right size so I rigged this up until Amazon packages start coming
 
Sounds like it got hot and went lean.

I run 20mm Mikuni carbs.
I’m at sea level..usually 60-80 degrees F temps.. and 70+ humidity.

My main jets are 110 and 130

I know it’s different carbs but the engines are similar.

Before you go down, I’d try going up on the main jet size. It’s not gonna hurt anything.
If it needs a bigger main and you go down in size you may burn it up.

Sometimes it can get confusing to determine the difference between a lean bog and heavy rich 4 stroking.

A lean tell tale sign is the engine will start out like it usually don’t.. seemingly lots of power..unusual screaming…then quickly fall off.
 
Try snugging down your cylinder and all the fasteners on the intake. When engines warm up, everything expands and air leaks can and will form.
Yes.. before you can tune you have to be sure of NO air leaks. It’s pointless to try to tune an engine with air leaks. The leaks have to be fixed first… if there’s any.
 
Yes.. before you can tune you have to be sure of NO air leaks. It’s pointless to try to tune an engine with air leaks. The leaks have to be fixed first… if there’s any.
Yeah I rechecked all the fasteners, and everything's snug. I'll try a bigger jet, like mentioned it can't hurt to be too rich. But the thing that helps back up my theory of being too rich now is that last night I was tinkering with it and at about the time it started acting boggy I accidently knocked the carb out of its rubber sleeve with my knee, and as soon as it sucked all that air it revved all the way up and ran for a good 2 seconds without the carb attached. Also, I have a 2bd apt and I use the second room as my shop as you see in the pic. I always keep the bike indoors and since I installed this thing that room reeks of burnt and unburt fuel and oil. Only other time that happened was when I first built the thing and was dialing in my fuel oil mix along with clip position on the HT carb. Just my observations tho.
 
Yeah I rechecked all the fasteners, and everything's snug. I'll try a bigger jet, like mentioned it can't hurt to be too rich. But the thing that helps back up my theory of being too rich now is that last night I was tinkering with it and at about the time it started acting boggy I accidently knocked the carb out of its rubber sleeve with my knee, and as soon as it sucked all that air it revved all the way up and ran for a good 2 seconds without the carb attached. Also, I have a 2bd apt and I use the second room as my shop as you see in the pic. I always keep the bike indoors and since I installed this thing that room reeks of burnt and unburt fuel and oil. Only other time that happened was when I first built the thing and was dialing in my fuel oil mix along with clip position on the HT carb. Just my observations tho.
So why do you want a bigger jet?
 
I don't I want a smaller one, I'm thinking I might have messed up and hit reply to the wrong post. Up above someone mentioned I should try going up in jet size, and I was just throwing that information out there to support my theory on why I need a smaller one. I was willing to give the guys theory a try, but science says it would make absolutely no sense
 
You can’t base an engines state of tune by how it reacts when the carb falls off.
All lean conditions come with fast clean high revs…then if it stays running heat follows.

If you do go down jet just be sure you know when to kill it if it’s headed in the wrong direction.
 
I recommended bigger jet because of the uncertainty. If I’m in any way in doubt which way to go on a jet change I go richer.
Reason being I won’t kill my engine if I’m wrong. If I go leaner and I’m wrong I may scorch my engine.
 
I recommended bigger jet because of the uncertainty. If I’m in any way in doubt which way to go on a jet change I go richer.
Reason being I won’t kill my engine if I’m wrong. If I go leaner and I’m wrong I may scorch my engine.
Yeah I'm still gonna give it a try, because I don't have anything better to do for now
 
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