350x Question - Won't run past 1/2 throttle

[MagicJames]

I went riding this weekend, and noticed about an hour into the ride the clutch started slipping, and i stopped and adjusted it a little. That didnt help, so then i checked the oil and the dipstick was HOT. I pulled it out and you couldn't even see oil on it. I put 1/2 a quart in the motor and then it registered almost full. I went to go take it out on the trail and took off from the parking lot, made it 50 feet up the hill and then lost all power. It still ran, but would not pull me and the machine up the hill. I put it in neutral and turned it around, and it barely had enough power to start rolling downhill. got it back to the parking lot and took off the seat and saw that the airbox to carb boot had slipped off the carb and was just partly covering the carb. I also noticed that there was oil all over the top of the motor, not thick but was just a light covering, and on the bottom side of the gas tank. Oil was on the spark plug cover and all over the front of the motor.
It still ran, but would not run past 1/2 throttle. it would die if i tried to get it wide open.

Any ideas on what went wrong?

[scottp597]

It doesn't sound good! I was hoping for a carb problem but it seems unlikely.... but you might as well make sure your filter is clean, and your intake boots are all air tight. Then the big question is are you getting good compression? Maybe it's a leaking head gasket or rings but I'm sure someone else with more knowledge can lead you in the right direction. Good luck!

[MagicJames]

I'm just kind of bumming because I had bought the motor and it was supposed to be fresh, and it just seems that my MO that if anything can go bad, it will.

Anyone have any ideas? I'm thinking about taking it to someone and having it looked over and tore down.

[sam12456]

Take off the valve covers. Inspect what it looks like take pics. Are you sure you tightend or checked all bolts. I mean you got boots coming off, and oil sounds like it's getting outta the valve covers. dont assume the worst start with the small things, just take pics and post em more we can see the better the help. Half throttle is prolly from carb boot coming off threw the pilot off, just like takin the airbox lid off. Drain the oil, take sparkplug out,kick over could be gas in the cylinder, new plug, new oil, and make sure every boot is on and bolt is tight might want to inspect carb too, take float boal off inspect/clean. I found jb weld in a carb once, I almost killed someone that day hahah.

[cbx1170]

motor parts will be hot. Clutch is clutch most likely separate problem. ck oil on level ground let engine sit a set time like 1 min, set dipstick on threads DO NOT thread in. Engine cks always do this in order Compression cks (& Leakdown cks) , Ignition cks , Carburetion. Leakdown is always best to do. In your case you also may have pulled something into motor. maybe pull plug and use small flex light down into cyl to see how compr area looks, look for anything sucked in. put in gear and turn motor a little. if rings are going you will have an oily combustion chamber with 3/8 of inch of "clean" but wet oiled piston all around bore edge at top ring land. center will have burnt oil thicker dry and built up. doesn't explain oil on outside tho. or if rings bad will pressurize crankcase and blow back into airbox thru crankcase vent hose. any oil in airbox? breather hose came off? compression ck and maybe leakdown if you have the tools and can hold crank from spinning. Mike

[oldskool83]

you got the right oil in there and or the right amount?

[MagicJames]

It still runs, and sounds like it has GREAT power until past 1/2 throttle. I'm gonna throw that other carb on there and then, take the head off and see whats going on and I'll post pics. Probably smoked the clutch :( Don't have a problem replacing it. Just want to make sure when i go through and try to figure out what went wrong that I don't miss anything. I'm not at all a 4 stroke aficionado and don't want to fix it twice.

[sam12456]

Its not the clutch they dont go out as easy as people think AND IT WOULD STILL REV ANYWAYS DUH . Its either carb or electrical, I had a 81 200 that had horrible scoring in the cylinder and it smoked bad and got hot quick, but it lasted forever. It never had single problem with revin up. just take the carb off take it apart clean it in a carb cleaner bath and put a new kit in seals and all then you know whats goin on and learn somethin too.

[beets442]

Do you run a inline gas filter? Sounds like it could be the main jet is clogged. +1 on carb dissasembled and cleaned, new plug and oil change....Beets

[atctim]

I had this issue on my 350X once - get into the carb and check your needle clip. Mine was gone - sounds like a carb issue to me.

[MagicJames]

Everyone is pointing at carb, so I'll start there. I was so pissed off that night i tore the motor out of it, so now i have to put the motor back into it and see what's going on.

[Dirtcrasher]

If it ran that low on oil, I'd sure be looking at my cam journals if I were you.

Even a "low" oil level was always an issue for the 200X and 350X and a seized cam makes it very tough for the engine to turn freely.

If it has BALLS from 0 to 1/2RPM I would also be looking at the carb but unless stuff got plugged (your filter did fall off partially) I can unly see the needle clip falling out and it's done it to me.........

BALLS without a load are different from BALLS under a load........

Thatt filter let some crap in so entirely disassemble the carb and clean out every orifice and jet.

[MagicJames]

It wasn't the carb that fell out. It was the boot that went from the airbox to the carb that fell off, right at the carb and was only half covering the carb.

[gary.h]

Make sure the Breather Tube on top of the Crank Case is there, I have seen these come off and at a steep slant it will blow oil out.... It should connect to a nipple right by the timing chain tensioner

Half Throttle thing sounds carbish... Good luck.. what does it do when you hit full throttle?? Die?? is there gas purring out the over flow on the carb?? (you would see it on the ground under the bike)
Does it blow white smoke?

You may need a new clutch.