Carb Jetting 101: Terms, Tips and Jetting Theory

[85 250sx]

yeah it only does it when i run out of gas. and well yeah at that time and moment its REALY lean since i have no more gas but should it rev like crazy like this on its own? i mean it sounds like im holding in the clutch and giving it gas wot. i dont think ive ever had this problem before on other bikes when i run out of gas on other machines they just kinda bog out and die.

[Dammit!]

I never run mine out of gas so I couldn't tell you how normal it is. I just know it's possible. Maybe risk some "duh!" replies and ask in trikesylvania if nobody else responds in here.

[toyota_guy83]

Ok guys, come and save my KLT 200 from my M1 Garand. I have spent alot of money and countless hours trying to get this thing to run properly, from swapping in a KLT 250 shift rod, new cam, rockers, valves, cleaned satan himself out of the carb, brand new oem spec spark plug, cleaned the fuel tank, replaced all the fuel lines, fuel pump and filter, cleaned the carb some more and still it bogs in what I gather is the needle jet circuit (1/4-2/3 throttle) I have tried every single clip position and screwed with the air screw for each one, the air filter is clean and airway not obstructed, intake boot is siliconed to the head and all hose clamps are tight. Tip in is great but if I try going past 1/4 throttle from idle it will stall out and die until I let off. Like it doesnt even fire. But if I rev it up a little into the mid range, it will rev fine at any throttle position. I'm losing my mind as images of FMJ .30-06 rounds pass through my mind. Can anyone help me please?

[Dammit!]

I'd post all that same info in trikesylvania. It won't get seen by a whole lot of people in here. Keep bumping it once a day if you need too.

[Xpress]

Good read. I pulled my T3's plug out to look over, and not quite sure if I'm running good. Feels like it's got plenty of low end and runs full throttle.



Based off of what I've read, I think I'm just a tad rich??

[FATALS1CKN355]

Hey guys! I know this is totally the wrong topic to be posting on , but I seriously need help ASAP. My 1984 200es Trike is bogging out at high acceleration , wondering if ANYONE KNOWS WHAT THE PROBLEM MIGHT BE. I've heard things about timing , but i'm not 100% sure. Thanks for reading , hopefully this doesn't get bumped or spammed because I'm in serious need of help! Thanks guys!

FATAL S1CKN355

[TurboTacoma]

Hey guys! I know this is totally the wrong topic to be posting on , but I seriously need help ASAP. My 1984 200es Trike is bogging out at high acceleration , wondering if ANYONE KNOWS WHAT THE PROBLEM MIGHT BE. I've heard things about timing , but i'm not 100% sure. Thanks for reading , hopefully this doesn't get bumped or spammed because I'm in serious need of help! Thanks guys!

FATAL S1CKN355

Have you checked all the basics first. Clean air filter. Clean carb with correct stock settings (unless you have aftermarket add on's, then jetting needs to be done to make it right). Timing in correct spot. Is the mechanical advance working... springs in good shape and lubed up. New spark plug. etc. I am only trying to help. I just got my 2 atc 200's and had to go through them both like I wrote above, and then once I had a baseline. Then I modded them. Hope this helps! Make a check list to help eliminate the guessing what maybe wrong.

[Nightmare]

What could cause alot of back firing on decel?

[vanaman]

Ok so im getting my 84 200x rebuilt. During this time im getting a 12-1 piston put in, unfilter, and a performance exhaust. I also bought a "new" carb off ebay for it.

Where should i start out at? Should i just buy the next few sizes above stock and try them all out or are their kits that i should buy.

What should be stock on this trike?

[Larry's Trikes]

I have been going through plugs every 3-4 hours and they are black and wet. Running rich I presume. They won't fire at all. I've dropped the needle valve one notch and no help. Do I actually need to reduce the maint jet seat size?

[torque]

i have read this entire thread please for give me if i missed the answer.

what causes backfire on decel.

i got into a fight lol on the board and want to be set straight.

thanks

[sbjones73]

ok people i have an issue with my newly installed 310 kit. a ittle information first.
85 250r esr 310 with a 38mm pj keihin carb. air box installed with cover removed and k&n filter in it. fmf fatty pipe and fmf silencer freshly repacked.

eddie sanders sugested running a 182 main and a 60 pilot. so i figured a little colder weather here in wisconsin right now, so i put in a 185 main and a 62 pilot.

this is what is happening. when i blipped the throttle, the rpm's hang up for like 2-3 seconds, then it idles fine. also, i have noticed that my idle adjustment (and choke on a pj carb) is like more than half way out (so half way choked)

so what i have done is played with my air screw. i am curently at 2 and a 1/4 out on my air screw (just checked) i have tried going in slightly to richen it up, but this did not really do anything.

so i need help here. i think i should should go one more up on my pilot jet, but what do you all think ?

note**** sorry for the double post. i put this in trikesylvania also *****

[4x4van]

Just as a bit of added info; Many have asked whether the pilot (air) screw adjusts air or fuel. Every carb is different, but there is an easy way to determine which your carb's pilot screw handles. If the pilot screw is located on the air filter side of the carb (before the slide), then it adjusts the air (opening increases the air, closing decreases the air). If the pilot screw is located on the engine side of the carb (after the slide), then it adjusts fuel.

[thcowboy]

i have read this entire thread please for give me if i missed the answer.

what causes backfire on decel.

i got into a fight lol on the board and want to be set straight.

thanks

What could cause alot of back firing on decel?

If it is backfiring on deaccelleration it is very lean