'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/showthr...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.