'85 200X rebuild won't run w/out choke on

[Qdude79]

Fresh rebuild with Wiseco 10.25/1 piston, UNI filter and DG exhaust. Have to hold the throttle slightly for it to fire. Set to high idle for the time being, it will not idle w/out the choke fully engaged. Give it some gas and take off the choke, it sputters trying to stay alive. I'm guessing it's lean, but it's hard to say if it's running hot as it's a fresh rebuild. Pilot screw adjustment seems to have no effect, possibly a bit better when fully closed. I'm thinking the stock 40 pilot jet might be insufficient. Was going to try a 42 or 45. Any thoughts?

[dougspcs]

You didn't mention if you cleaned the carb during your rebuild..

Sounds like some of the dirt from the float bowl got pulled up into the idle jet..pull the carb off and strip it down.

A good cleaning, blow the jets out with compressed air and it should be good.

[atc007]

ANYTIME you go to the work of a rebuild,you clean the carb and tank thoroughly. This will eliminate these problems. You didn't mention what overbore,and if you threw this pipe at it with the piston or it was on before the rebuild. You will probably end up stock,or 1 or 2 mains above stock. But you simply have a dirty carb right now.

[Scootertrash]

Clean your carb good, as Doug said blow compressed air thru all the jets and passages in the carb,make sure you can see light thru the jet. Then read this:

http://www.3wheelerworld.com/showthread.php/55086-Carb-Jetting-101-Terms-Tips-and-Jetting-Theory

[Qdude79]

Sorry...Bored .20 over. Carb thoroughly cleaned and rebuilt during rebuild. Tank redone and clean. Every nut and bolt on this thing has been cleaned/painted/powdered.

[dougspcs]

How does it ride out? Power is good?? Of course your pilot jet you were talking about is not for idle, high speed only so really has nothing to play into an idle issue.

Given what you have said it sounds like the carb is coming back out and getting rechecked.

But you didn't mention how it runs out..is the power good at mid-high speeds??

[Qdude79]

Power seemed fine for what I expected...I'm used to my 350X. What would I check?

[dougspcs]

Power seemed fine for what I expected...I'm used to my 350X. What would I check?

Just on the off chance that the running problem was related to being out 1 tooth on the cam, but your acceleration and top end speed would be terrible!!

It would be instantly apparent when you were riding it so it can't be that..

Back to the carb..out she comes for a recheck I'd say.

But as a second thought..pop the CDI cover, set the engine on TDC compression stroke, spot the 'F' mark on the flywheel in the spotter hole. Now with all that totally lined up, check the pickup/exciter alignment..the marks need to be spot on!! This might be a bit of spark timing issue perhaps..

[oscarmayer]

that means it's not getting enough fuel at idle. the idle mixture screw. what is it at? for stock starters, turn it till it in till it stops (not tightening up at all), then turn it out 2.25-2.5 turns out and start from there. when you rebuild the carb, what is the needle set to? stock is middle, put the clip 1 down from center. the jets need to be slightly bigger than stock as well. your stocker shoudl be a 110 main, you need a 115 main now, and the idle needs to go up 1 size.

[Qdude79]

Needle is in the middle now, I "believe" I put a 112 main, didn't change the pilot. Pilot jet screw has very little effect as it stands. So go to a 42? Should I get the 115 main while I'm at it?

Thanks Oscar.

[Qdude79]

PS- Anything I should look for with the float when I open it up to change these jets? I don't recall doing anything specific when I rebuilt it last summer.

[atc300r]

Did you adjust the air screw.It should be around 2 turns out.Also are the gaskets and o-ring in the intake manifold good.

[threewheelin-feelin]

Did you adjust the air screw.It should be around 2 turns out.Also are the gaskets and o-ring in the intake manifold good.

i was about to ask about the intake...sounds like an air leak maybe if it only runs on full choke

[Qdude79]

I'm fairly confident the manifold is tight, but I hadn't thought of that, so I'll check it later today. Good point. Thanks.

Doug- checked timing initially, but I'll pull the CDI cover and check there, too, just to eliminate the possibility. I'm so carburator challenged, it a good idea to eliminate all other possibilities.

[oscarmayer]

yes on both questions. go with a 115 main and get the 42 idle. check mixture screw. 1.5-2.5 turns. start at 1.5 and then turn 1/4 turn at a time will you get good results.

[dougspcs]

Man these guys have you hoping with ideas..

Don't get your head in a knot over this jet VS that jet...stock jets and settings will make it run. The rest you can dial in later!!

KISS (keep is simple stupid)..

If it isn't running, there is something basic wrong..stay on that course and don't get overwhelmed from all the input..

You know your close..just slow down and you'll figure it out.

How about that timing??

[Qdude79]

Gonna check timing and intake when I get home. I see your point, Doug, but I'm willing to take advice of guys that know a lot more than I do about this things.

[1984 honda 200s]

I just fixed a 250 suzuki quad tonite, the lad said it only runs with choke on and dies when you give it throttle... i rolled my eyes and said ok. BEEN THERE
Its running lean, the choke richenes it up restricting air flow,,, drop your throttle plunger needle down 2 slots or one at a time and you will notice a BIG difference, dropping the needle clip richens it up !
I droped his from 2nd notch to 4th notch and ran like a champ, took it up and down the street with a big smile on.

[oscarmayer]

any word on this?

[Qdude79]

Not yet. I'm hoping the new jetting will come in soon. Need to check for air leaks and the CDI while I wait.

Sidenote: I wrapped the header last night and fired it for a few minutes to burn the water off. Being dark, I rolled it outside the garage for fresh air while running and noticed a glow from where the header meets the head, almost to the first bend. To me, this indicates a lean condition. We'll see...

[dougspcs]

Not yet. I'm hoping the new jetting will come in soon. Need to check for air leaks and the CDI while I wait.

Sidenote: I wrapped the header last night and fired it for a few minutes to burn the water off. Being dark, I rolled it outside the garage for fresh air while running and noticed a glow from where the header meets the head, almost to the first bend. To me, this indicates a lean condition. We'll see...

Alot of the time a glowing red header is because of improper spark timing or rich running condition..one or the other will cause combustion to take place in the pipe instead of in the cylinder.

Also your replaceable jets are not for idle mixture control..

Again..back to the timing check friend!!

[Qdude79]

Agreed. Timing, along with air leaks is still very much on my to-do list.

[oscarmayer]

Not yet. I'm hoping the new jetting will come in soon. Need to check for air leaks and the CDI while I wait.

Sidenote: I wrapped the header last night and fired it for a few minutes to burn the water off. Being dark, I rolled it outside the garage for fresh air while running and noticed a glow from where the header meets the head, almost to the first bend. To me, this indicates a lean condition. We'll see...


did you notice it smoking or smelling very rich? pull the plug out and post a photo. i want to see if your lean or rich. i have seen this caused by both lean and rich conditions depending on what is happening. do NOT run the bike again till we figure this out. it could melt pistons and such...

[Qdude79]

Will do, when I get home in another three/four hours.

[JJMF1979]

I am having a very simular problem with my 200x running a supertrapp so I am following this closely hope he and me have good luck and solve our problems soon, mine is a little worse though because I am also sure I am burning oil and either need to do valves or piston rings I think at first I thought it was just oil burning off from when I layed it down for a cpl seconds to paint the bottom of the engine but it hasn't stoped and the oil dropped in it

[Qdude79]

Snuck home quick. Here ya go:
http://i276.photobucket.com/albums/kk39/qdude79/633fd94d.jpg

[oscarmayer]

your running lean

check your float adjustment in the carb. also is the filter on the petcock cleaned up? it looks like your not getting enough fuel and i am thinking something is restricting flow. so check the petcock (take it out of the tank and clean it and confirm no clogs and screen is clean) then take carb off and check float. the easisest way to check is to have the carb upside down and the floa sectin that is sticking up should look to be perpendicular (sp?) to the case of the carb where the bowl bolts to. if it's level to that, you should be "ok" of not adjust the tab till it's level.

i thought it wwas lean, but wanted to view the plug to be certain and that is definatly signs of lean conditions.

[oscarmayer]

one more thing you can do is put the clip 1 up form the bottom of the needle. that will richen it up some.

the mixture screw, turn it in till it stops and then turn it out 2 turns. see what that does.

[Qdude79]

Thanks Oscar. The fuel petcock is clean, as it was just installed.

I'm thinking that the float level is a likely culprit. I don't recall doing ANY adjusting or checking of the float level. I'll try the needle change, too. Would you still suggest going with the 42 pilot and the 115 primary?

I'll work on it this weekend, and yes, I WILL be checking timing and air leaks for certain.

[oscarmayer]

try the float and needle first and go form there. I still think you'll need at least a larger main, in the end, but that may be it.

[Qdude79]

Ok, needle moved up to second from the bottom. 42 primary installed. Float visually checked, sits level. Waiting for the 115 main in the mail today. Haven't thoroughly checked for leaks yet, as I haven't fired it, but all seals/gaskets I've inspected taking the carb off/apart look good. Waiting to fire it, hopefully tonight, and check timing. Fingers crossed....

[Qdude79]

But as a second thought..pop the CDI cover, set the engine on TDC compression stroke, spot the 'F' mark on the flywheel in the spotter hole. Now with all that totally lined up, check the pickup/exciter alignment..the marks need to be spot on!! This might be a bit of spark timing issue perhaps..

Doug (or anyone), can you be more specific on what I'm looking for on the "pickup/exciter alignment?" Timing is the last thing I want to check before trying to fire it again and I want to be sure I know what to do so I can get on with this thing. Thanks.

[Qdude79]

Thank you one and all, specifically Doug and Oscar! I still have more fine tuning to do, but it's running WAY better with the new jetting and needle setting, and YES, the timing was slightly off. When getting it to TDC, the adjustment was slightly retarded. I lined them up dead to nuts and, with the new jetting/setting, fired right up. Let it warm up a bit, killed the choke, adjusted the idle, sounds great! More fine tuning to do (I need to read up on plug chops), but MUCH closer to the mark. I thank you, gentlemen.

[oscarmayer]

n/p man! that's what we are here for. :)