My '75 DT250B sat for a month or so while I re-did the tank, redkote, etc. Put it all back together and now it bogs down at anything more than half-throttle or so. Starts, idles, and putters around fine, but when I give it a twist, it bogs down and the engine nearly stops. When I let off the throttle, it behaves normally again. I'm hoping I don't need to try and get inside the carburetor (I'm scared I'll screw something up), so before I go that route, I'm hoping for other suggestions. It's fresh fuel, new fuel line, new in-line fuel filter and as far as I know, fuel is flowing from the tank without any obstruction. I'm thinking it's in the carb, but that's why I'm asking. Thank you for any help.

Jeff

have a look at the filter on your petcock Jeff, as you've been working on the tank there might be some debris blocking the filter screens

Thanks for the reply. I rebuilt the petcock while I had the tank off - all new gaskets, etc. Both petcock screens are clean and unobstructed.

Jeff

yeah but maybe some of the new coating has come off? I dont believe much in coincidences myself.

You could just disconnect the tube from the carb and see if there's a good strong flow of fuel when you turn on the petcock

I'll try that. In the meantime, I removed both the pilot screw and idle screw and blew some carb cleaner in the holes. It didn't help...

Jeff

Basic one, but whilst doing the tank work and polishing did you ensure the vent hole on the filler cap has not been blocked

Hadn't thought of the cap on the tank. Shouldn't be an issue though- didn't do anything to the cap and it was running fine before.

Jeff

If you've polished the tank with the cap on it can get blocked. If you run the bike and it starts bogging down, open the cap and see if it helps

UPDATE: It is not the carburetor. Had a friend far more knowledgeable than I take a look today. Fuel delivery is fine, no plugged main jet, no plugged anything. No vacuum lock either. We're leaning toward the problem being an electrical gremlin now. Frustrating is the word.

Jeff