Question For All Esr 310 Owners

[CODY_M11]

I HAVE A ESR 310 AND STOCK CARB AND OLD ADJUSTABLE LRD PIPE. WHAT DOES EVERYONE RUN FOR JET SIZES? RIGHT NOW IM RUNNING A 200 MAIN AND THINK 45-50 PILOT. JUST REBUILT AND FIRED IT UP AND RUNS BUT WONT IDLE. JUST DIES OUT LIKE ITS CHOCKED OR NOT ENOUGH FUEL. I DONT KNOW MUCH BOUT TUNING CARBS SO WHAT DOES EVERY1 THINK I SHOULD DO? BIGGER MAIN, SMALLER, BIGGER OR SMALLER PILOT? RUNS GOOD JUST WONT IDLE. AND I HAVE ALSO MOVED THE NEEDLE UP AND DOWN AND GOT A LITTLE BETTER BUT STILL WONT IDLE.

:confused:

[FL-R]

Mine has a 52/200. But also a 38 A/S.. Then again its blown up 2 times in 2 months. Good luck.

[Honda 250r 001]

I would say you need to run from a 48-52 pilot. And i would think that you would need a leaner main jet. As im running a 180 in my 310 with a pwk 39 carb.

[Langbolt]

What's your AIR screw set to ?

How many turns OUT ?

Try it at 2 turns from slightly seated.

If it idles better (and off Idle response )with it out more then You need a SMALLER Pilot Jet.

If it needs to be turned in further then you need a BIGGER pilot jet..

Also,

Is your CHOKE on ? Or turned all the way out/In ? Try adjusting it there as well.



:devil:

[CODY_M11]

I have tried pilots 48 to 52 today and mains 200 to 210 and no better. I rode it today and no power past ht and have adjusted the air screw all the way in and out but cant remember which way it ran better. Also adjusted choke all way out and in. Im starting to think in going to big on jets so and going to start at 45 pilot and 180 main and see what that does and go from there. Also adjusted the pipe but didnt help any.

[CODY_M11]

hod do i know what size or model Keihin carb i have?

[Honda 250r 001]

Originally posted by CODY_M11
hod do i know what size or model Keihin carb i have?


I think the reason you have no power is because your main jet is too big. I would go down to 190 and see if it runs better

You measure your carb by taking a caliper and measuring the smaller side of the bore in mm. If its stock, it should show up as somewhere around 34.(00-75), if its a 36 it should show up somewhere around 36.(00-75)

I hope this helps

[CODY_M11]

well i ran the 175 main and 60 pilot like esr website recommends and it still wont idle.

[Ruf Racing]

That's a huge pilot jet.

[CODY_M11]

Ya i thought 60 was a huge pilot to but thats what esr recommended. So today i changed back to 48 pilot and 180 main and still wont idle. Rode it and took moment before it felt like it wanted to take off and hit power band. Than after couple minutes cruising down road it lost power and died. Fired back up but just slowly cruised back to truck. Anyone have a clue whats going on with my carb? Found out i have a 34 pj carb.

[Aceman]

Clean your carb.
Adjust your float.
Then read this:

http://www.duncanracing.com/TechCenter/KeihinCarbJetting.pdf

[CODY_M11]

man i have completely rebuilt the carb. its not dirty.

[Honda 250r 001]

ok man look. We have given you the tools you need to get your carb set up correctly. Your 250r is dying because its not getting fuel, the petcock is prolly plugged. You cant just say. I went from a 200 to a 180 and it still runs bad. OR i went from a 60 to a 48 pilot and it still doesnt ldle... Did you adjust the air screw? did you adjust the idle screw? IS your carb even put together right? IS your float set? You have to be more descriptive. It could be more things that the carb. Do you have any air leaks? Reeds good? compression? whats your plug gapped at? What color is plug?

[250rPRIDE]

your way to rich period.. 48 pilot and 175 main.. put a new plug in it and run 50:1 or mabe 40:1 with good synthetic 2-stroke oil and high octane fuel.. make sure your air fuel is good and choke is off, check to make sure you have good spark, but ya sounds like your way to rich

[CODY_M11]

i have cleaned the petcock. took completely off and cleaned with carb cleaner and blown out with air gun. i didnt say i went from 200 to 180. i mean i have tried every jet from 180 to 210 and the same with the pilot. i have adjusted the air and idle screw exactly the way the manual states. float is set right and carb is put together correctly. have done a air test and no leaks. brand new v force carbon reeds. compression is 160 to about 175 with a plug gapped at .32 . plug is clean on electrode. no color.

250rpride, i will try the 48 and 175. i have a new plug in it and a new cdi with a bright white spark so that is not the problem. i use ams dominator but i will try 50:1 or 40:1 and i am running highest octane pump gas we have.

[250rPRIDE]

let us know how you make out.. also its hard to believe but i have seen carbs go bad, no matter what you do to them they just wont work.. but why dont you look for a new carb a 38mm as or a 39mm pwk.. you can find them for around 100. often. it will make it run way better, trust me you will be very pleased with a bigger carb, what type depends on your riding style.
Pete

[wes350x]

I had a jetting issue and I tried a buddys carb and WOW, mine musta been bad. I think it was the needle seat, but I purchased a new 38a/s and I believe my jetting is 50/180 with my 310. Im dead on now. Spend the money and get a better carb. I went through all you are doing. Also I gap my plug around 0.18. Go tighter on your gap.

[406Z26]

Another thing to think about is what ignition are you running? Stock? CR? And i hope its not a DynaFS!

[CODY_M11]

Well i got the jetting to the point where it runs just wont idle. I will be doing a vaccum and leak down test soon and hopefully that tells me something. Going to try some new reeds too. I am running a stock ignition.

[Pumashine]

Originally posted by CODY_M11
Well i got the jetting to the point where it runs just wont idle.

There is no idle screw as you said you adjusted previously. The idle is controlled by turning the choke knob one way or the other. I am not sure if you have done this but I have had to show a handful of people where the idle control is on a stock carb. Just trying to help.

[CODY_M11]

ya i have tried that puma. no help and if i said idle screw i meant air screw lol. but i just thought of now that i might mess with the throttle cable to see if i can tighten it enough to get it to idle. that may work.

[skyhighatv]

Over the years w the different r's ive built ive found that when my jetting is spot on it wont idle and thats the way i like it. usually if your bike idles your prob lean in the pilot/needle. I personally ride high rpm mx xc style and always have the throttle pinned,w my riding style if my bike idled id prob have burnt up lot of pistons if i was jetted that way,hope this helps.-jaysin

[slamdak8782]

Listen buddy what you need to do is look at it like three different circuits. First things first if your running a 310 get a bigger carb a 34 is pretty small. Im on stock bore with a 39 Air striker. Secondly take it all apart inspect for cracks in the float make sure that the needle on the float valve is moving smoothly in the bore also look at it and make sure it is cleaned out. Ok now select a pilot valve and work on the idle first. Once you have the idle set by means of the pilot size and idle speed adjustment. Ok its idling now so work on needle drop or raise it work through the adjustments of the needle by means of the clip position. If you are all the way down on the clip position which raises the needle in the bore and you are to lean raise the main jet up a size and set the clip all the way back up lowering the needle eventually you should have a nice smooth running engine through out the powerband. If you start lean and work your way up eventually you will find the money spot for the settings. But you need to get it idling without running hot. If it is hot it is lean. Hopefully this clears it up for you. By the way I had a 34 and it was crap and would never adjust so I upgraded which you should do to take advantage of the cubes

[slamdak8782]

Also when it starts on the first two or three kicks your pretty close on the Idle circuit. the needle is mid range adjustment and the main jet is WOT. Dont try riding it lean or you will be sorry cause it will probably get toasted. So you see it progressive the mid o top ranges are related a little in that main jet can affect the mid range however mid range can be spot on but WOT be off. Its all about the steps low to high and you should set it in that order. So if mid range is good but WOT is not ok no problem bigger main jet then go back and dial in the needle clip position. If you really want to get specific grab a lser thermometer and moniter the Exhaust temps this can help dial it in closer. Anyways I hope that helps in some way I know that I went kinda in depth there. This is how i jet. Also once you get it dialed in play around with different need;e profiles they can change the way the power comes on find one that you like.

[tritty_wall]

CODY_M11
Did you figure out what was wrong with you motor, becuase i'm haven the same trouble. I think it might be air leak but not sure. Thanks

[CODY_M11]

No I haven't yet. I had it running good to where it just wouldn't idle on its own than changed oil to fuel ratio and made it run horrible. I think it is an air leak but I just found out my gf is pregnant so haven't really been paying much attention to my quad. If I do have time to tinker. With it and figure it out ill let ya know. Or if you figure it out post your solution to the problem please. Thank you