Mailine,
The 1437 ohm coil is a common coil used in most 80's, 125's & 250's, as is the high tension coil (Spark plug coil), from some 78 & most 79 models onwards, its the 500 ohm coil that is the hard one to get. To my knowledge, without looking at ALL models, it was used in the YZ80F to 80K, 125F & G, YZ250E to 250H only.(Dont quote me there may be more) If you want my advise I would get one from "Bert's Small Coils" in Geelong Vic, last time I checked it was about $150 change over but that was a few years ago. The thing with coils, or anything electrical, is that they really need to be tested under load. Multimeters are a good start but really are just a continuity tester, especially digital ones. Even though they are the easiest to use and read (Digital multimeters) an analogue one is better because it gives real time testing. What I mean by that is while you are testing you can watch the needle for any movement which can be a sign of insulation break down, you know, fine when you first start it then runs like a dog when it's hot. The best way to test would be with a mega that puts 500v though them to check for such break downs.
The other reason to go new is new coils tend to give much better spark in that the build up and release of magnetic flux is so much cleaner & quicker. These coils set the advance/retard curve of your spark as well as providing supply to the CDI. The better the coils the better the spark & the more precise the timing will be. I have seen bikes with different coils and different cdi's, they will give spark and will run the bike but if your lucky it will just run badly but the melting of pistons is a very real consequence.
Hope this helps.
Viper666
Love & support to those affected by these horrible fires!
