Carb type and size

In your opinion what would be the ideal carb and what carb are you currently running, this post is mainly for flat karts running round dirt tracks. I have a 212cc predator motor. I'm selling the 28mm mikuni....yes it's a genuine mikuni.
 
A animal or Lo 206 for gas , carb should get you going . If that don't work something else is wrong .
 
It really depends on what's been done to the engine. It all plays a part in what carb to run.
Really the only thing that has been done other than the obvious of fitting and rebuilding is the head has been ported and bigger valves, the jrpw level 10 head. A stock appearing .690 carb will make it run but not give it the power I guess the cam is a 9000 rpm cam.
 
I would have said a 28mm Flat-slide PWK mikuni or the far cheaper copy type are just as good, but you appear to have one and are selling it......but is it a round slide?......am I allowed to ask, what went wrong when the 28mm mikuni was fitted?.....whatever type it is.
 
It's a flat slide, everything seems to be in place correctly, nothing seems to be fitted wrong. It just that when I give it part throttle or full throttle the engine somehow does not like it and I don't know what that is or why. It has 32mm intake valve so theoretically the 28 should work on it. Stumped is my guess that and running e85r instead of good ole gas or methanol which I know absolutely nothing about.
 
I would double the pilot jet size .
If it improves theres your answer. Or use the enricher same if it is better at taking throttle its lean on the pilot .
A shot of either same thing .
 
If its flat slide mikuni PWK 28mm then you have the best carb already. Some use a 30mm, but the 28 is a darn tidy carb. Sort your jetting and emulsion, even the wrong plug type causes the problems you have, but I admit it doubts carb related.
 
who built the carb? did they jet it for the fuel you are running? What is the timing set at? Again is timing set for the fuel you are running?
 
who built the carb? did they jet it for the fuel you are running? What is the timing set at? Again is timing set for the fuel you are running?
If its flat slide mikuni PWK 28mm then you have the best carb already. Some use a 30mm, but the 28 is a darn tidy carb. Sort your jetting and emulsion, even the wrong plug type causes the problems you have, but I admit it doubts carb related.
It was jetted for alky as I was told by jrpw, he told me to send it back so I did, said he found a few problems and sent it back to me, it has the arc ultra light finless flywheel with 32° of timing built in flywheel. I told him when ordering that I was running gas, bro in law insisted we run e85r. Emulsion tube I was told I didn't have to change. Here is what I ordered...and here is a pic of the 180 jet that he said was wrong....
 

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WOW I just got confused... you had the carb set up for methanol, told arc you're running gas, but now youre on e85.... is this correct?
 
WOW I just got confused... you had the carb set up for methanol, told arc you're running gas, but now youre on e85.... is this correct?
I bought it from jrpw, it was ser up for alky by mistake from jrpw, told him I was going to run gas, bro in law said use e85, is that the issue?
 
I WOULD THINK THAT HAS ALOT TO DO WITH IT. I AM NOT SURE WHY HE WANTS TO RUN E85 METHANOL IS THE WAY TO GO BUT YOURE GONNA WANT TO BUMP YOUR TIMING UP TO 36 AND PLAY WITH IT FROM THERE. YOUR BUILD IS RADICAL ENOUGH TO WARRANT METHANOL OR RACE GAS. IF E85 IS A MUST YOU NEED TO TELL THE CARB BUILDER THAT FOR SURE IM SURE JETTING IS DIFFERNT THAN GAS.
 
YOU DEFINATLY HAVE THE RIGHT CARB JUST NEED TO GET IT SET UP FOR WHAT FUEL YOURE GOING TO RUN AND THEN TUNE IT WITH A BUILD LIKE THAT I WOULD BE HAVING IT DYNO TUNED FOR SURE.
 
I WOULD THINK THAT HAS ALOT TO DO WITH IT. I AM NOT SURE WHY HE WANTS TO RUN E85 METHANOL IS THE WAY TO GO BUT YOURE GONNA WANT TO BUMP YOUR TIMING UP TO 36 AND PLAY WITH IT FROM THERE. YOUR BUILD IS RADICAL ENOUGH TO WARRANT METHANOL OR RACE GAS. IF E85 IS A MUST YOU NEED TO TELL THE CARB BUILDER THAT FOR SURE IM SURE JETTING IS DIFFERNT THAN GAS.
No need to scream but methanol I know absolutely nothing about, don't even know who to talk to about it..lol, nothing has been don't to the block other than gut it.
 
YOU DEFINATLY HAVE THE RIGHT CARB JUST NEED TO GET IT SET UP FOR WHAT FUEL YOURE GOING TO RUN AND THEN TUNE IT WITH A BUILD LIKE THAT I WOULD BE HAVING IT DYNO TUNED FOR SURE.
I would love to have it on a dyno, but I would also love a hands on to show my where and how or what I'm doing right or wrong.
 
I run NR Racing 390 alky carbs on my open Chinese stuff. Never ever have had a problem with either (we do purge with gas/oil after every race night) and this is the 4th or 5th season I have run them. Nice smooth power from 4000-9000+. And no knobs to mess with.
 
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LOL NOT SCREAMING SORRY IM AT WORK AND HAVE TO USE CAPS FOR CONTRACT STUFF AND JUST LEFT IT ON. JRPW ARC AND JUST ABOUT EVERY OTHER ENGINE BUILDER KNOWS A TREMENOUS AMOUNT ABOUT METHANOL. I THINK YOU'LL FIND MORE READILY INFO ON METHANOL THAN E85 FOR THESE TYPE OF ENGINES. ALOT OF GUYS WILL DYNO WITH YOU IF YOU ASK
 
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