Hey Puffs, what is going on? I know you wrote it, but still is sad to see you gone from this forum...
Yes, my bike....In the last 30 days I had covered about 700 km, drove it practically every day, if weather was fine....mostly with no specific problems, but in the last week MZ started to disbehave...
When accelerating it started stuttering, with very similar sympthoms like the forum member TS 250-1 described in one topic. At about 90 km/h the "stuttering" started and shortly passed after accelerating further. In the following rides things just gets worse. To the before mentioned stutter issue joined backfire and bogging down, what was before smooth ride....From my experiences with old TOMOS mopeds, those were the signs of bad spark plug and obstructed fuel supply. Also worn points...
So I had changed the spark plug and the bike works almost just fine, with ocassional stutter, but nothing like that, that did before. Luckily, I was just around the corner of my street. At home I dismantled an old BVF 30n2-5 and I was surprised, how clean it was. No signs of any dirt in the jets, the air and carb cleaner went through the jets perfectly. But the tank, fuel filter and both filters on the fuel tap were severe clogged with rust particles. I had cleaned all but I think, that this is not the only problem...
The backfire on twostrokes is more electrical thing ugess Well, on MZ is either electric or carb. I had ordered a new points, coil, capacitor and spark plug cable. I had cleaned the contacts to the actual ones, but at the moment the tank is off the bike for cleaning and I am waiting for a new fuel filter and fuel line to come, so I can't test it.
BTW, the slide in the carb was a bit sticky and it has signs of wear, also mixing chamber. I had used some fine wet and dry and now is buch better...of course, the bike must run and then we will see....
I have no experiences with points adjusting or changing the whole set. there in nothing useful on youtube, but this. Maybe the man on the video is forum member https://www.youtube.com/watch?v=FI_c70bER14
Any advices are appreciated