Used aftermarket condenser as I couldn't locate an OEM one.

I will give that a try. Thanks.

Yeah, a brand new one made no difference.
THanks.

With all you're saying, condenser is the best bet at this point.  Aftermarket ones just plain suck sometimes.  Some are bad right out of box. 

Can be hard to find NOS ones...  Quality Ford, VW, or Mallory condensers installed up by coil work fine..  just have to connect and insulate the wires and remove original condenser from stator. 

Wire it "straight from the mag black wire" in the mag loom direct to the plug coil. Did you look into the flywheel in the dark & see what's sparking & jumping around. LH main not fallen to bits. Had that once on an AG100 where the cage broke & all the balls had a party in one spot pretty much & crank was gyrating around. Was a CDi model farm bike but could play up even worse with points. Doing the black wire thing bypasses everything else, switch, loom, you name it. Coil might be orange at the coil but whatever there's only one wire in!!.

Tried to use a timing light but can't get it to start at all now.

MarkT,
How do I determine which condenser to buy if I get one say for Ford?

Hi,
Not sure I follow what you are suggesting. The way mine is wired there are three wires soldered to the condenser. Black wire from source coil, wire to the points, and black wire to the loom for the ignition coil.

One more thing to try on a DT175.  There is a diode in the stator harness in the points wire from 1974-76 or so.  It's right before the harness connector to the main harness.  Should also be a test pigtail coming off harness that bypasses the diode. Disconnect the harness plug and and run a wire from the test pigtail to the ignition coil.  Or cut out the diode from the harness.  It's only there to prevent engine from starting backwards.  I've personally only had one go bad and it prevented spark completely.  But semiconductors can do weird things.  (I just replaced it with wire but DEET might have an original diode if yours is bad.)

If that doesn't work this forum has about every topic and question answered...  many of them dozens and dozens of times.  Midlife Motor moved his DT175 condenser and while it's not exactly how I do it, his method works fine.  others have done it too but he did a nice write up 

Can be found here:  yamaha-enduros.com/index.php/forums/74-7...er-relocation#106154

I like the big mallory racing condensers...  a magazine wrote an article in the early 70's on moving condenser and they claimed the Mallory was the best performing.  Unfortunately they are NLA...  I still have a couple someplace and probably can find them on ebay.  But I can't say they do work better in my experience. 

Other than that I've used late 60's early 70's Ford pickup truck V8 condensers up to whatever year they went electronic ignition.  They are cheap, every parts store had them, and work good.  Also I used VW beetle condensers because I think I STILL have a couple in an old box of parts someplace. 

Doesn't seem to matter much...  and it's easy to swap out once you do the hard part. 

Be VERY careful to make sure wires stay clear of spinning flywheel parts which can be harder than you think.  While you are in there, make sure none of the stator wiring has a bare spot in the insulation.  Seen that a few times and can cause intermittent problems that are hard to find.    Inspect carefully.