Nevermind, just made one out of quarter. Not the cleanest but itll work.
 


Oddly enough its still running like crap. 




 

Its bogging/chopping out in the upper rpms.

EDIT. I was trying to upload a video but I guess you cant do that here. 

 

Upload to YouTube and then post link here.  Automatically embeds into post.

The jet is a 140, which I believe is the leaner one going off of partzillas list. 

My needle was in the middle and I moved it 1 click leaner and it ran slightly better, then I moved it to the last leanest clip and it ran like crap again. Not sure if the sputtering has to do with being rich, but IDK. Gonna get a new plug and see what happens.

Any chance this is electrical/timing? 

Yes.  Sounds kinda like electrical cutting out.  Have you tried charging battery up and seeing if it makes a difference?  The 125's can be sensitive to battery voltage.  Make sure points are clean and connections tight.  Key switch in good shape?

The bike just came off the battery tender in that video. Ill have to go through and have a look at all the connections again.

Do you know if there is supposed to be any electrical contact on the cam lobe for the points? It looks like theres a little wiper thing that drags on it. There is some surface rust on the lobe is why Im asking.

Its the lobe on this piece.

 

No electrical contact to lobe.  Cam needs to be smooth and clean.  Wiper is to lubricate. 

Hard to find proper points rubbing block lube these days but NAPA can probably get you a tube of Standard Motor Products SL2 lube...  a tiny amount should be placed on leading edge of fiber points rubbing block.

You can use a couple drops of oil (literally!) on felt wiper but I always use the SL2...  Oil has a magical way on getting on points contacts and fouling things up.

Ok, I went back to the stator area and sanded every possible contact I could see. The only one I couldnt get to was the wires going to the points. I dont have wrenches that tiny. Will figure out how to get to it. 

The points gap seemed super tight. Checked the manual and it says .30-.35mm. I dont have feeler gauges on me right now, So I looked up the thickness of a dollar bill, .11mm. So I folded it 3 times and set it to that. 



To late to start the bike right now, so we shall see tomorrow. Ill also clean all the wires under the tank and the kill switch. 

Hi Torqueflight, my carb spring plate was also 'missing' when I stripped my carb down and rather like you I thought no probs, simple little device I'll make one can't be too difficult can it... . 

Challenges:

Central hole has to be EXACT, big enough diameter for the top of the needle valve to stand proud through it BUT small enough diameter to NOT allow the needle valve E clip to pass through it otherwise as you said the needle valve 'floats'.

The little tabs on the original item help locate the spring plate so it 'locks' the throttle cable nipple into the carb slide body.  (My prototype kept turning I think due to the spring contacting it).

Finally my throttle action was sluggish and I believe this was because my prototype acted as a blanking plate turning the carb slider into a 'damped dashpot' rather than a free moving slide..!!

The moral of this story for me was not to be a penny pinching tight@rs*  and instead swallow hard and buy the proper item, which I did eventually from Germany for €14 inc P&P....aargh !!