Help with my 84 250r it's shutting off

[Jesse'sGirl]

Hey guys, I'm having a problem my 84 r is shutting Off when it gets hot after riding it for 30 mins, what to do?

[30rack]

Does it run correctly and consistently?

Are you able in any way to replicate the shutting off issue? such as a throttle range, gear, something?

Are the engine and carb set up correctly?

[3wheelerfan1991]

Sounds like electrical to me.
I've had issues with coils before. After it gets hot, it sputters, goes slow, then dies.

[Jesse'sGirl]

it doesnt sputter when it shuts off, it kinda just dies.
about the shutting off, i hav'nt went out for that long of a ride yet, but im hoping to go tonight. im not sure if the carb is set up 100% but im pretty sure the enginne is.. as for i did all the work myself, and the only thing is that my 5th is not working also. i was pretty sure it was all right. ill also post a picture of my spark plug. theres a DG fatty and a stock can, is that ok to run. is there a differents in the jetting or fuel? i have the stock pipe too but its cracked atm.

[RIDE-RED 250r]

Make sure the fuel tank vent is clear. If not, as fuel is run out of the tank enough vaccum builds to cause fuel flow to stop

[Jesse'sGirl]

yes its clean.

[atc300r]

I run a Cobra headpipe with the stock silencer on my 83 250r/300r.It runs great .

[Jesse'sGirl]

Alright, should it sound like it has a cam when idling?

[yaegerb]

If you did all the engine work yourself you will need to tell us about it. What is the compression, are you using aftermarket reeds, any carb upgrades, etc.

[Jesse'sGirl]

It's all stock as far as I know, it's bored over 6th and I put new crank bearings and seals in.

[RIDE-RED 250r]

yes its clean.

Ok, if you don't have a fuel supply/metering problem then it's likely you have an ignition problem.

How long do you have to let it sit before it will run again?

[Jesse'sGirl]

Well I just went for a ride and after 45 mins, on the way home it die. And I had a bottle water with me and I put it on the motor and then it started. The time before that I let it sit for 10 mins or little longer. I'm gonna go try a different stator, I don't, have another coil. What do u mean by fuel supply metering problem?

[Jesse'sGirl]

My airscrew is at 1 1/8 and my needle (clip) is in the middle, i also just put a new carb kit in. Br8es Is the right plug too be running right?

[Jesse'sGirl]

here also the picture of my plug.
147159

[RIDE-RED 250r]

Well I just went for a ride and after 45 mins, on the way home it die. And I had a bottle water with me and I put it on the motor and then it started. The time before that I let it sit for 10 mins or little longer. I'm gonna go try a different stator, I don't, have another coil. What do u mean by fuel supply metering problem?

By fuel supply I am referring to a problem with the fuel tank valve, vent, needle and seat and/or float in the carb not letting fuel in from the tank.

By metering, I am referring to proper float adjustment or if the float is sticking. If the float height is too high or the float is sticking it could cause it not to let enough fuel in for the gnein to keep running. Basically the fuel suply can't keep up with what the engine is consuming and eventually running low enough for the engine not to run.

Sparkplug pic is a little fuzzy, but if it's kind of gray in color you are too lean. I can't really put my finger on if it is mainly black or if it's kind of grayish. But the fact that cooling the engine with water made it run again suggests you are overheating it. Very possibly due to a lean condition.

[Jesse'sGirl]

So its over heating, bc its to lean ? What way does the clip go again, for riching ?

[RIDE-RED 250r]

It's possible to overheat from a lean condition.

If you are talking about the needle clip you would want to put the clip in a lower position, thus raising the needle and richening the fuel mixture. This will only effect mixture on the midrange. If it is lean from 3/4 to WOT then you would need to replace the main jet with a step or 2 richer. Or if the problem is in the off-idle to 1/4 throttle range a pilot jet change would be needed.

[Jesse'sGirl]

How much bigg with I go, I think I might need a bigger jet then is it on to still ride it ?

[RIDE-RED 250r]

Figure out what size jets you have in the carb now and get the next 2 sizes richer for each (main jet and pilot jet).

But we still need to be sure the problem is jetting related. Can you post a clearer picture of the sparkplug?

[Jesse'sGirl]

Is it ok to stilll ride it? And I think I may need a main jet, My needle is a 103, yes I'll get another picture, I just went for a ride to the pit for a little to see if moving the needle richer helped, but it didnt. it's the same as you will see. How much r the jets around?

[Jesse'sGirl]

here are some picture of my plug , the first one is the best.147165 147163147164 how are there ?

[WJG1000W]

looks lean to me and yes it is bad for two strokes to run lean

[Jesse'sGirl]

I have my cip on my needle at the bottom as for im mixing my gas at 26 to 1. How can I fix that just use more oil then ?

[RIDE-RED 250r]

No, oil mix ratio is not what is causing the lean condition. The lean condition is about how much fuel is mixed with the air that's being inducted into your engine.

Ok, so, we need to be sure we are on the same page as far as nomenclature... You say your needle is a 103? Are you talking about what is known as the main jet? The main jet is found by removing the fuel bowl and looking for the brass hex head that sticks out in the open. Can't miss it. In fact, it can usually be accessed by just removing the fuel bowl drain plug. If in fact you are saying your main jet is a #103 than that sure seems lean to me. Now, I don't know the jetting specs for your '84 R, I am only familiar with '85-'86 jetting specs. But in my mind what you have seems lean.

As to the price of jets. You will usually find them online for $6-$8 US. Try sites like Jetsrus.com. Or a google search will net you multiple sources. But remember you will need to know your carb brand and type as one type of jet does not fit all carbs.

[Jesse'sGirl]

I have the stock ones in my other friend had a look, its like a 31 i think but yeah that's what is says on the needle 103N. so when I go to look for them is it just the next # bigger for richer jets? I'll check that out, also there a place intown that may have them, they have my carb kit.

[Jesse'sGirl]

My needle is a 103N and main jet is 130 and my pilot jet is a 50, my Carb is a keihin.

[RIDE-RED 250r]

I have the stock ones in my other friend had a look, its like a 31 i think but yeah that's what is says on the needle 103N. so when I go to look for them is it just the next # bigger for richer jets? I'll check that out, also there a place intown that may have them, they have my carb kit.

Not to be a wiseguy, but I have no idea who in your town might be able to get jets for you. Best I can say is if you have a motorcycle/atv dealership in the area they should be able to help you or at least point you to someone who can.

Your 103N needle is not the main jet, it is the jet needle. The main jet is the brass hex fitting that protrudes from the carb casting you can easily see when the float bowl is removed. If you are at 130 now, try getting you hands on the next 2 sizes larger. Should be something like 132 and 135 give or take a digit. They skip around a bit sometimes changing in increments of 2 or 3, but you get what I'm saying. Same for the pilot jet. You might be ok with your pilot jet you have now as it only effects off idle to 1/4 throttle. But it might not be a bad idea to get the next size larger.

It is difficult to say exactly what to try as I don't know at what throttle range your engine seems to be running lean. You have some homework now, get a few jets, start out rich and work your way leaner a step at a time.

You will have to put a little effort in this yourself, I don't have all the answers. You have a Keihin carb, but what type? Size? You will need to know these things (especially type) when looking for your jets. I am not as familiar with the 1st and 2nd gen 250r's so I don't know what exactly you have to begin with.

[Jesse'sGirl]

So guys I don't think it's to lean bc the piston was black I took it part again to just look at everything, I didn't a leak down test it said its good.. I have 175 to 185 compresstion, the plug is black and wet a bit, that's what u want right. Also sometimes with it get really hot it sometimes just keeps revin up I checked my reeds there good.. They are metal ones. It's still overheating, it smokes really bad so I still don't think it's lean. But I'm hopefully getting jets by friday. I'm not sure what's wroung could it be my stator not 100% in the right spot?

[RIDE-RED 250r]

Yes, improper ignition timing due to a sheared flywheel key can cause overheating as well. But the engine is usually very difficult to start with a sheared flywheel key.

I'm sorry to say but I am about out of ideas Jesse. It's tough to diagnose a stubborn problem like this without laying my hands on it myself.

Your plug being black and wet tells me it is plenty rich, but the revving and overheating is indicative of a lean condition. Something isn't right somewhere...:wondering