All you 250R experts

[BigThumper33]

I've lost all hope. My dad and myself as stuck on what to do with his R. Something is wrong and we can't figure out what it is.

It bogs thru 1st, 2nd, then hits 3rd and hauls *** up to 6th. We have done all types of jetting changes....I can't figure it would. We have tried two stock carbs and still have no luck. We put on a new coil just for kicks and didn't notice anything. I'm stuck...

[Chef]

What kind of gas are you running? Switch someones carb, get some brand new gas, and check it out. My 400 did this, and it had rust and all kinds of junk in the fuel.

[beerock]

how about some details???????

youll never get any help by just saying what u said.

we need details to help

carb size? main jet size? pilot size?

what plug are you running? and hows the plug look?

is your tranny full of oil?

how about the reeds?

[BigThumper33]

We are running 91 pump gas with premix. I've switched carbs.....not working. My dad has been messing with it for months. I finally got sick of him complaining and decided to dive into it myself. When I took it apart I couldn't believe the jetting specs he was running, He had a 135 main and still would not stop fouling plugs and it didn't blow up. I upped it back to stock settings and still have not seen a single change in performance.......its doing the exact same thing. And it fouls plugs like a myth! Can't figure it would. We are running a 50:1 premix ratio....

The gas is clean.....I've tried two carbs.....and I'm still stuck

[BigThumper33]

I can't post jettings specs because I've tried them all......literally.

The reeds are good.......I've checked that twice, no gap, no damage to the cage.

The tranny oil should be fine......haven't checked that. Don't see how that is related please educate me?

It is the stock carb, 34mm I believe? I've tried two.

The plug is an NKG BR9ES. It burns alittle rich looking, and fouls about every 30 minutes of riding.....Runs like a raped ape when your on it over 2nd gear. Bog it or slip out of the power band and you're likely to foul. I've tried leaning out the needle and pilot......and air screw....everything that adjusts lower rpms......and still have not seen any difference.

[beerock]

ok first things first, switch to a br8es plug, it will burn more fuel and be easier to jet.

I asked about the tranny oil because you could be sucking tranny oil into the bottom end in two different ways, the right crank seal or the center gasket.

I think you need to take your pipe off and look up the exhaust port and the intake port for a seized ring or scuffs on the piston wall.

defineately change the plug....

and check your tranny fluid to make sure the motor isnt burning oil.

what 2 stoke oil are you running?

[BigThumper33]

Okay, I'll tell my dad to run out and grab a few BR8ES plugs.

I'll check the tranny to see if its burning oil. We blew up the R last year and had it rebuilt. I think its .060 over right now. Since then we really haven't had it up and running right since. It doesn't have many hours on it thats for sure. We are running a yamalube oil...been running it in our R's for years...so I don't think its the oil. The first R we got was running it so we stuck with it ever since......

[Teufel]

check the rings also. to do it right you will have to pull the jug. I would do a compression test before tearing it down. If the piston and rings have alot hours on it I would freshen it up. Then move back to the fuel system.

Good Luck

[beerock]

i'm not flaming here but the last two posts, teufuel and TRX.

do you guys read past the first post?

both of your suggestions were already addressed. WHY confuse the guy?

also, if you read he said the top end was rebuilt and hasnt played with it much. so the top end is fresh. BUT with a 135 main it could be likely a ring is seized.But you dont have to take the top end off to determine that.(thats a waste of a base gasket and some time)

thanks.;)

[BigThumper33]

Beerock, heres some more info to help out.

He started at a larger main and began working his way down because it was running like crap even with a larger jet, took it all the way down to 135 and was suprised it didn't lock up and it still made no difference. Not even making it worse......just no difference. I don't know if the ring is gone or not, but that is obviously not the initial problem. Since then I've upped the jetting back to stock and still nothing. Still fouling plugs and the engine has some mods.....so in theory it should need an even larger jetting spec.

What I dont understand is how it can run flawlessly from 3rd and up to 6th. But 1st and 2nd just suck, its like it has to clean itself out.... It won't rev up much in neutral either....just stumbles.

[airheadedduner]

Pull your stator cover off and check for rust or other deposits. Clean up the flywheel if needed. Your stator could be failing. Being you rebuilt it check out your electrical conections, make sure everything is tight and snaps into place solidly.

[beerock]

i think you said you replaced the ignition?

You could have a bad ground.

your problem could be a number of things.

but the br9es spark plug doesnt help at all.

You could have a scenario of the rings on the motor not seating properly and your getting blow by at low to mid throttle response.

are you SURE you cant get it to rev out in 1st or second? like maybe slip the clutch in second?

it could even be possible that your key way broke and the fly wheel isnt timed right.

maybe you have a clogged fuel line?

it could also be possible that your carb is just flat out worn out. this happens alot with the stock carb and could be the reason.

can you get your hands on a good carb?
maybe you should buy one as an excuse for some more power even if its not the problem:)

[methyman]

It sounds like there is a air leak in the motor. Check your motor cases for cracks or possible gaskets leaking. Need to plug your exhaust and intake and apply 10 psi to the motor and spray all areas with soapy water and look for bubbles. Just my 2 cents. Good luck and I hope you find whats wrong and keep us posted on what you find.

[Newbie400ex]

I kind of agree with beerock. Check your fuel line,tank,filter it could be clogged just enough...

[beerock]

Originally posted by methyman
It sounds like there is a air leak in the motor. Check your motor cases for cracks or possible gaskets leaking. Need to plug your exhaust and intake and apply 10 psi to the motor and spray all areas with soapy water and look for bubbles. Just my 2 cents. Good luck and I hope you find whats wrong and keep us posted on what you find.

No, if he had an air leak the motor would be lean all the time, in his case he is RICH. so there isnt a airleak, UNLESS its on the right side which would burn oil and give a false rich reading.

I suspect it has more to do with the rings seating but I am still unsure i need more details.

[BigThumper33]

I'm postive it wont rev. Even in neutral. Its very weird.

It seems to come to life in 3rd gear. As if the choke is on until 3rd. It bogs hard. Like a light switch. On off On off.

We put the new coil on just for kicks....it was doing this before we installed the new coil....thats not the problem.

I don't see how the rings have anything to do with it as well. It started when we were still running it at a rich state....then my dad(with his great wisdom) leaned the damn thing down to a 135. But the thing is is that it is still running rich! Plugs are black...

Beerock the key may be the issue. But usually when timing is off doesn't it get worse as rpms go up considering the gaps will be more noticeable? I've never heard of timing being off at 2-3k rpms and correcting itself at 8k rpms.

I think when the snow melts off a bit, I will start off with the BR8ES and see what I can gather. I have a few buds I may be able to steal the carbs off of. My dad is set on that its the carb and wants to go aftermarket. He is a low end trail rider, if it does turn out to be the stock carb, which carb offers nice throttle response and bottem end performance? I heard nacs sells one...

[Bean]

id check that right side seal bee is talking about, a good carb is a Airstryker 38mm, thast what i have, good bottom end

is your headgasket any good?
possibly bad ignition wires, sparkplug cap

only things i can thikn of

[airheadedduner]

A coil and stator are completly different things. If you could have someone test your electrical system. The specs are in your shop manual(if you have one), it is not that hard and don't take that long if you got a good tester. A dirty/rusted stator will not show up on a tester.

[BigThumper33]

I know the stator and coil are seperate. I was telling beerock before I installed the new coil it was still bad.

I will check out the condition of the stator. I always have hated dealing with the electrical junk. It always seems to be guess work! I'm so sick of this thing......but I love it when shes going :macho :blah :scary:

[surfer]

long shot, but, i've noticed with ALL 250R's condensation on the stator. open up the stator cover, if its damp let it dry out over night, then put it back on and run it

[Bean]

the reason for that is, them coil wires that head into the case right next to the stator cover, water goes in through that rubber sleave right into the stator area, but it is a sealed area, so it cant get out and it pools up and messes with that stuff.

i drilled a small hole in the bottom, threaded it, and installed a grease zerk WITHOUT that little ball and spring thing, so basically stuff can run out like water, and air can circulate to air it out

[FatBoy Redrider]

I'm no expert but either are the guys who have answered so far. I have messed with jetting on my R so many times. No one has told him to do the obvious!!! You are only talking about your main jet. What about lowering or raising your needle? What you are talking about is the area before you would hit the main jet. Try adjusting the needle and it will lean it out. I can't remember if it is moving the clip on the needle up or down that leans it out. If it is that far off you should be able to tell though. I would try this before I think it is anything else. let me know if it works.

[airheadedduner]

How does it run if say........you are wide open in 5th then let off the throttle and hit it again?? Is the response crisp??

[BigThumper33]

I have tried adjusting all parts of the carb, air screw, pilot, needle, and main.

Once it gets to 3rd gear and over it is a beast. I can hit 5th, rev it out, let off, and still get on the gun again. It has been over a month since I've last rode it so I'm trying to remember how it is running. There to much snow out to take it out right now.

[airheadedduner]

If it is doing that it really sounds like the stator to me. Pull off the cover and look at it, it won't take more then a few min.

When my stator got condensation and rusted like surfer said it had the symptems that you discribed. If I rode in anything under 3rd it would foul out in no time. I cleaned it up and presto, all good. On mine it was okay half through 3rd and up.

[phatswinn]

did you break it in correctly? cuz if not the stress of getting up and moving on the motor could be bogging it down and wearing it prematurly, as a resault you get loss of compression and worn rings letting tranny oil through but at high speeds its less time to let compression thru, i know for a fact compression is a vital fact to make a 2 stroke run right, i would do a compression test cuz when i bles my engine it was minor on my rcon and it would start but u had to have it revved about half throttle to keep it running (we were 60 miles from camp), luckely 250R's arent hard to do a top end rebuild urself on and its not a big cunk outta ur wallet for a small bore and hone, it also sounds like your pilot and idle setting may not be in tune

[BigThumper33]

Talked to my dad and he said he has checked the stator and she is clean as can be. Does anyone have some electrical specs that the stator should be putting out and where I need to hook up the ohmnmeter to get a reading?

[Teufel]

a Honda manual should show you those specs

[wilkin250r]

Why does it matter what gear it's in? That's the part I don't get. Why does it run different in 2nd gear than it does in 3rd gear? I agree that it will run differently at 2000 rpms than 6000rpms, but it should run the same (rich or lean) at 4000rpms in 2nd gear as it does at 4000rpms in 4th gear.:huh

[BigThumper33]

Thats what I think! I don't see how it runs better in 3rd and up than in 1st and 2nd! I have no clue....

[310Rduner]

i wont even guess about your prob.

but, if you want a carb with the Best low-mid end then you deffinetely want mikuni TMX. has better low- than a/s and wont fall on its face for top either.

esr has them for 220 compl with billet jet board and jets 420-480.
good deal i love mine.

good luck with your prob, id deffinietely milk your dad for that carb while you can.

[BigThumper33]

That TMX comes at 220 complete. And 420 with an entire array of jets? I'm trying to get this straight.

It's not my quad, so I don't really care much about it. But its sad seeing it just sit there. He would probably bite on a aftermarket carb for 220 anyway.....even if thats not the problem lol

[310Rduner]

yah, honestly its ot like you need an uxcuse ahha.

yep $220 complete with billet jet board and about 8 jets, i wrote down ones i got when i received it, and i have 360 to 460 main jets. the jet board has ESR enscribed with a laser on a solid, nice piece of billet. nice little extra


when i got mine i also purchased a new throttle cable, old one wasnt as smoothe. also got cr 250 intake boot, but ive heard you can get away with heating up stock one to fit the 38 intake.

got a bit more expensive, but so way worth it :macho:o

[airheadedduner]

Originally posted by BigThumper33
Talked to my dad and he said he has checked the stator and she is clean as can be. Does anyone have some electrical specs that the stator should be putting out and where I need to hook up the ohmnmeter to get a reading?

The manual says 50-200ohms. Ricky Stator says better off 180-190ohms.



Whoops that is for the source wire thingy. I think it is a black wire with a white stripe. One thing you also might wanna check is if the sparkplug wire is broken on the inside.

[dhines]

As several people have said, the fact that it runs well in higher gears but not at high RPM's in lower gears make this a really unusual problem.

The only difference to the engine (that I can think of) between 1st gear at a high RPM and 5th gear pegged is that more air is running across the bike. Of course the way that most snorkels are placed it shouldn't make much difference.

Anyway, I know it sounds completely off the wall and overly simple but have you checked for some kind of obstruction in the air intake system - snorkel, filter, carb boot, etc. That would also account for the rich condition.

Just a thought...

p.s. - might be worth checking the pipe too. Dang mice!

[BigThumper33]

My autobody instructor told me to check the pipe out for mice as well. I'll be doing the ohm meter thing tonight and he also stated that I really should look at the pilot jet. He said if there is anything plugging it up it will not flow and overflow into the main circuit to soon.

I'm lost.....I hope I can figure something out!

[BigThumper33]

All electrical components are A okay.

After further carb investigation (along with some better education) I've found some gas contamination. I took the bowl off vertically.....so no gas flows out the over flow. This way it did not disturb the bowl that much.....I found a lot of grit/dirt/etc whatever! My instructor told me to look for this and that the grit can easily clog the pilot jet becuase of its small size, causing an over flow and kicking the main circuit on to soon.....thus running rich. I hope this is the problem.

I told the old man to get a in line filter and some carb cleaner tomorrow. I'll put it back together tomorrow night and see what happens, I've put all jetting back to stock specs.