Got the motor all together and back in the bike. It fired right off on starter fluid till the gas filled the fuel bowl, then ran off the gas. Sounds wayyyyy better than it ever did.

But back to an issue of old. So I had it running for several min. I bled the oil pump and made sure the engine was getting oil. Its working.

It ran for a few min then died. Pulled the plug and there was spark. Put the plug back in and nothing. Just coughing if I keep the starter held down for like 15 seconds. Wont even kick on starter fluid, not even a hit. Its like something warms up and it wont spark with the plug in, but if I pull the plug and ground it to the head there is spark. This is same thing it was doing before. I dont if the coil warms up and then just puts a weak spark out. I think I should replace the coil and condenser.

those battery ignition coils overheat and can be damaged if someone leaves the key on with engine off.  That would be my first guess

Check out Economy Cycle in Texas... RD parts but I think the RD350 coil is the same as yours? He used to have Hitachi at a good price.  (Or at least I used one on a 125 e-start). Try discount code 2SW

Thanks, getting a new coil and condenser guess we shall see.

Ordered a cheap coil just to test it that it. If thats it Ill get a good that you mentioned.

Is there any cross over with the condenser? Doesnt seem to be easy to find for 1974.

Just found one on ebay that ships from FL.

Coil and condenser came both dont fit.

Coil only has one orange wire instead of 2, orange and brown.

Condenser wire is too short and mount is on the wrong side. Still wired it up, still back fires.

You could rig up any standard old points-type automotive coil if you have one off an old VW or something. 

Single wire is magneto coil. 

 

Same with condenser.  Old Ford truck (early 70's) condensers used to be available everywhere cheap and I used them a lot before the "world inventory" showed up on this thing called a computer.  It's so much easier to find parts now than it used to be when I was younger
 

Only mentioning the following as you say--'still backfires'--Have you had the generator armature off the crank.
Is there a chance the crank key has broken off & armature slipped taking the timing with it.
Or has the advancer points cam moved. In theory it can't because its located by a tag i think.
I might've already said similar going back pages--not sure.
I have a drawer full of RD350 coils but half a world away but must be plenty close to home. Good coils. Even had one on my Lada Niva haha & that doubled the Niva's value.

I used the Economy Cycle coil on my DT125A referenced above. Set timing while in there and bike ran great. RT325's comments reminds me,  I took
my timing advance cam off and blasted with baking soda, then oiled it well.  Improvement was noted.