Thank you,I do. And I will keep playing with that. I’m wondering if I need to get the proper tools and check the timing.
I’m assuming the coil and condenser are good as it starts and runs normally.

Hi Wally,
I had pretty much the same problem on my buddy's bike. It was a spider building a nest in the vent tube.
Do you have a " vented fuel cap ?"
Blow it out with compressed air . Cheap and easy fix.
wear a helmet and let er' rip.

I’ll give it a try, thank you.

Idle screw "in" in theory should be super rich. If not why not. If set as it should be as said in above post then how does it start & run.
Does it idle lean or not want to idle & not want to start either--like its way too lean.

Hello from Florida, USA! Thanks for the add. My name is Robert, I’m 30 and have been riding since I was 5 years old. I grew up on dirt bikes, both leisurely trail riding and racing for a few years as a kid. I bought my first street legal motorcycle, a 1986 Honda CMX450, when I was 15 and spent the summer rebuilding it and rode it through my high school days. Since then I can’t even keep track of how many bikes I’ve owned and ridden. I worked for Harley Davidson for 6 years and my main bike is currently a 2001 HD Wide Glide. Also in my current lineup I have a 2002 Yamaha V-Star 650, a 1999 XT225 “Serow”, and a recently acquired 1977 “Balboa Blue” DT250D true barn find (which is the reason I joined this forum). The DT needs a full rebuild to get running again, looks like most of the mechanical parts are there and the engine kicks over and seems to have compression, but it is missing all of the  lights, gauges, and side panels, the wiring is a wreck and the inside of the tank is pretty crusty. But it’s just something fun to tinker around with on the weekends. Not really planning on doing a true restoration, more of a rat rod “mad max” apocalypse style build using whatever random spare parts I can find and just use it as a little street thrasher/hoonigan bike for some local fun around town and maybe the occasional trail ride or “green lane” when traffic is an issue. Hope to pick y’all’s collective brains and tap into the wealth of knowledge for guidance as I embark on this journey with the almost 50 year old enduro. 

from near Salisbury, UK.

"But it’s just something fun to tinker around with on the weekends."

I remember saying that same thing about 12 years ago. Have fun and enjoy the ride.

Greetings from Tennessee