The trouble with those bikes is they have no oil pump, only splash feed and bottom ends don't last long. Also the ignitions are shit and fail regularly. I had one and it made an old maico look reliable
I think that the big-ends in these motors would last ok if the owners had used good oil & changed it regularly . After all, Husqvarna used this same design (with no oil pump) right up till the '96 TE610 . In Australia, it seems that many owners treated them like XR Hondas & rode them with long intervals between oil changes . I think that the guys with modern high performance fourstrokes, like YZFs,CRFs,RMZs ,KTMs & Bergs , have now realized that you have got to change oil frequently if you want them to last . I would agree that the ignitions couldn't handle heat & failed regularly , especially on the '83 model which had the stator mounted behind the flywheel . The '84 model had the stator mounted on the cover , outside of the flywheel to try to keep it cooler , but they still were unreliable . But for VMX use , where the races are usually short , I don't think that heat build up would be a problem & the ignitions should last .
