High altitude carburetor jet kit for honda, predator, clones

Oil pan 4

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L185 turbo
Sep 21, 2017
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I have a Honda clone made by kohler on my log splitter. A 196cc.
It runs real rich. There's soot around the exhaust. I'm at 4,400ft above sea level and use ethanol free gas, so yeah she a bit rich. I ordered the "high altitude kit" from my friendly local everything dealer, a month ago.
You think all I would have to do is simply look in the manual, order the kit. Nope it says "contact local kohler dealer".
Called Monday, still on back order...
So I figure I'll hop on ebay and find one real quick. Nope.
Start searching and all I find is hopped up go-kart stuff. I figured that might work. Pulled my jet to see what size it is. It's a #65, which means 0.65mm or about 0.026 inches. Yeah 99% of all the go-kart jet kits are all way bigger like #70 through #100. Eventually I found one kit with a #65 which is what I already had. Observing size increments going bigger I figured the next smaller sizes were probably going to be #60 and #62.
So I'm pretty sure it's Honda part number 99101-zg0-0620. Change those last 4 numbers to get what you want, say -0650 for a #65 or -0600 for a #60 and so on.
I also found a go-kart kit for Honda, predator clones with #50, 55, 60, 65, 70, 75 and 80 jets. I have several of these clones running around so having a bunch of different jets will be handy. There doesn't appear to be 59, 61, 63, 64, 66, ect jets available.
So between the 60 and 62 I ought to be able to get it dialed in.
What a pita.
If you buy a predator clone they come with altitude jets, but you're sol if you buy an engine attached to something.
 

Mark_BX25D

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Dunno if it's true, but someone once told me that, while new jets are the best solution, going one heat range hotter on your spark plug will do almost as much good.
 

GeoHorn

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Removing the foam air filter will also help. (if you don’t mind the unfiltered air. a paper filter might work)
 

#40Fan

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Jul 21, 2022
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I have two Champion 2k Watt generators that I soldered the hole in the jet closed, then used a smaller, than original size hole, drill bit to open them back up. Nothing was available at the time.
 
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lynnmor

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B2601-1
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Why not try ethanol laced gas, if E10 is still too rich, try E15. You just have to remember to run it dry before storing it for a long time. Yes, I hate the corn squeezens as much as anyone but it might be an easy solution to your problem.
 
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GreensvilleJay

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assuming the jet IS made of brass...
remove from carb ...easy
clean it shiny...easy
heat and fill hole with bronze...dang HARD
drill hole .025 = #72 bit..easy

possibly 'sleeve' the existing hole with brass tubing or teflon ?
maybe use a syringe 'needle' ?
 

Yooper

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assuming the jet IS made of brass...
remove from carb ...easy
clean it shiny...easy
heat and fill hole with bronze...dang HARD
drill hole .025 = #72 bit..easy

possibly 'sleeve' the existing hole with brass tubing or teflon ?
maybe use a syringe 'needle' ?
Use solder instead of bronze.
 
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GreensvilleJay

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I thought of that while typing, wondered if it'd 'wear' but reading your post ..hmmm...not exactly like the gas is going 100MPH though the tiny hole, so yes solder is real easy...
Used to repair gas tanks with it,so has to be 'compatible'......
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
107
43
NM
Removing the foam air filter will also help. (if you don’t mind the unfiltered air. a paper filter might work)
It's pretty dusty here, best I could do to lean it out was remove the air filter cover (during operation) that makes the engine draw hot air off the engine, giving it coldnair intake and removed the spark arrestor.
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
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I checked on the tune kit with all the different jets in it. It's on a slow boat comin over from chii-na.

I'm going to try to order a #60 from a US vendor.
Also looks like #58 is an official Honda size so might as well get one of those too.
 

Oil pan 4

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L185 turbo
Sep 21, 2017
412
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NM
Why not try ethanol laced gas, if E10 is still too rich, try E15. You just have to remember to run it dry before storing it for a long time. Yes, I hate the corn squeezens as much as anyone but it might be an easy solution to your problem.
That would definitely help as stoichiometric air fuel ratio for pure gas is 14.7:1 and stoichiometric for E10 is about 14.1:1 just switching to E10 should get me about 7% leaner.
I figure it's set up to have the ideal mix at sea level with ethanol free, so I'm about 12% too rich here.
If set up to run perfect at sea level on E10 gas, then I'm about 20% too rich here running ethanol free gas.
Yah know what, I knew switching to E10 would make it a little leaner, but I didn't think it would be that much. Now that I looked it up, I know. I can go buy some e10 swill until the Jets come in.
 
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Oil pan 4

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L185 turbo
Sep 21, 2017
412
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Time to use the splitter again. I defueled the ethanol free gas and got 3/4 of a gallon of e10 dishwater. But the #62 jet should be here today.
I guess I can run it as is on e10, when the mail is delivered later today I can switch over to the #62 jet and see if it sputters on e10.
I also have that #60 but it's on a slow boat over from chi-na. And at #58 from the same place.
If you know what jet you need they're only about $7 delivered, with ethanol free gas being over $3.50 to $4 a gallon it could easily pay for its self in fuel savings. And the proper A/F mix will wash down the cylinder less allowing the engine bore to last longer.
 

Oil pan 4

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L185 turbo
Sep 21, 2017
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I gave up trying to tune the epa approved carburetor and sht canned it.
I bought a cheap clone. Tuning a non emissions carb is much easier.
 
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Oil pan 4

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L185 turbo
Sep 21, 2017
412
107
43
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It looks like the knockoff carb uses a bigger fixed air bleed orifice. That allows more air into the emulsifier tube, more air makes a leaner mix.
Running a #65 makes it way too lean. Won't stay running with out the choke.
Next size up I have is a #69. It still sputters a bit at full load wide open throttle. I'll try a #70. It's definitely running leaner at idle and unloaded.