That is high. I know that about 40-50 percent of the first two years' 8010's had the same problem, too. That was way higher than any other combine, until the 70 Series John Deeres were introduced. It was about that, for the first few hundred 70's. In 37 years of observation, I've never seen such a high percentage of fires, period. My theory is that plastic holds/generates more static; add to this, the fact that today's combines are all full of electronics, more wiring than a three bedroom house and a lot more hydraulics than just 25 years ago.
Why is it that combine manufacturers don't even have recalls like the auto makers do? I think it was only a rather small number of Ford Pintos that actually burned, but the recall was fast and effective. At the same time, at least 4 out of 5 or even 9 of 10 Model 815's [International Harvester] with those dual exhaust stacks, burned during their first three years. IHC made no recall on those.