XR200 Jetting

So I have an 86 XR200 that I've installed had a moose racing air filter on it when I got it. Everything else seems to be stock. For some reason the Pilot Screw has to be turned out to like 5.5 turns. When I got the bike it had a factory 38 pilot jet so I thought I would try a 40 and even with the 40 pilot jet in I couldn't really turn the screw down that much. I guess what my question is should I get a larger size pilot jet so I can turn the pilot screw down? The bike seems to run pretty well so what would I gain with a larger pilot jet? Is it just important to have the screw set at a certain limit or is it just a starting guideline. From what Ive read about setting the pilot jet it is never really clear and the service manual is not really clear either. Basically I warm the bike up and set the idle control to where I think it should be. Screw the pilot jet in until the motor dies. Note the position. Set it back at factory position. Restart the bike. Turn it out until the bike stops. Note the position. Then split the difference. Is this correct? Any input would be appreciated.

Too many turns out. More than 2-2/2 turns out indicates too small a pilot jet, an air leak, or a fouled discharge port. The carb has two low speed discharge ports in the floor of the venturi that are fed by the pilot so if one fouls the other can't flow enough gas to make up for the loss. I suggest a good cleaning. Cleaning Carb

Your method of adjusting low speed mixture gets you close. Honda has a strange way to adjust the low speed mixture on the XRs so I suggest a more conventional way: adjust the mixture screw for best idle, then reduce idle speed and re adjust mixture for best idle, repeat. Then set idle speed to your preference. This usually provides best running and easiest starting. A final check is if there is exhaust popping on decel (a little bit is OK) this indicates a lean low speed mixture, a fouled discharge port, or an air leak.

I went and rode all day yesterday and the bike seems to be running better than ever. The pilot screw is still adjusted out to around 5 turns. I do however have some exhaust popping on decel. I have not had a chance and did not read your suggestion to clean the carb before I went to ride yesterday. But I will definitely do as you suggest. I do also suspect that I may have a slight air leak in the boot coming from the air box. It does have a small crack close to where it attaches to the back of the carb. Would I need to buy a new hose/boot (not sure exactly what to call it)? Aside from it being recommended in the manual to set it at 2 1/2 turns what is bad about it. I mean is it going to hurt the motor over time. It's not that I don't want to fix it and I will fix it but I'm just trying to understand the negative impact that it will have if it is out more that recommended. Because like I said it is running great the way it is. Thanks Chuck for your help.

A leak in the air boat won't affect running, just lets dirt into the intake.

I don't have a manual handy but my recollection of initial setting of the mixture screw is 1 1/2 turns out, then fine tune from there.

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