multimeter reading help please.

[kawaboy-zx12r]

Hi. i just got my multimeter in the mail today (never used one before) i got it because my 1984 YTM200 has intermittent weak spark issues. i think the problem may be my pick up coil or my charge coil. i just tested both of them. according to the manual the pick up coil is suppose to be 196 ohm, which it is (the reading bounces between 195 and 196 ohm) but my charge coil is suppose to read 386 ohm but it reads 398 ohms. is that enuff of spec to be my problem? Thanks, Dennis

[christph]

Usually the manual will give you a range, i.e., 120 to 180 ohms, not a specific number. I rewound a stator recently and had a 60 ohm window to work within. I doubt being off by 12 ohms is a problem. These values change as the stator heats up anyway.

[kawaboy-zx12r]

i just re-checked manual and it says + or - 10% for the values given. you are correct, i checked them cold, before riding first and got the 196/386 readings. then checked warm after riding and got 227/480.

[kawaboy-zx12r]

would you think being 100 ohms over on the charge coil when warm could be my issue? the manual does not state to check warm or cold. i think it could be a grounding issue also, i need to check all my ground wires, it started running good again when i was riding it to warm it up.

[Sargon2112]

Kawaboy,

I expect the manual gives you cold readings, and yes, the readings would be higher when the parts are warm, as the resistance of copper increases with temperature, like christph said. I am an electronics engineer, and a three wheeler nut. Sounds like those readings are good to me.

[kawaboy-zx12r]

ok thank you for the info. i appreciate it.