Re: F60 starter update- Rodbolt & others
ok<br /> how the starter drive works.<br /> when the solinoid is activated by the keyswitch the contacts close allowing a very high current to the strter.<br /> a DC motor has incredible starting speed and torque, as long as its getting current, in fact all it "knows" is it is not going fast enough and wants more current to go faster.<br /> if current gets limited, either from battery output not enough, bad connections or cables that are to small the starter starts slowing down.<br />the very rapid start of the armeture turning causes the heavy drive to ride up the inclined plane of the shaft. in otherwords newtons law that says a body at rest tends to stay at rest works.<br />now that the lazy drive has engaged the flywheel it starts turning it. the only way it will fall back down and go to sleep again is if somehow the flywheel speed exeeds the drive speed.<br />once the drive starts falling total narcolepsy takes over and the armeture can spin till the battery dies and it wont come up again.<br /> in an internal compustion engine as the piston compresses the air once it starts back down the air pressure tends to accelerate the crankshaft and flywheel.<br /> as the flywheel is much larger than the pinion if the pinion cannot get enough current to out accelerate the flywheel it drops.<br /> it loses the race.<br />its all about who can spin the fastest and why.<br /> could be your battery cannot supply enough current fast enough, could be you have a poor connection, could be the cables are to small or the starter motor is defective.<br /> nice thing about lec tric ity,<br /> voltage and current are proportional.<br /> if resistance goes up so does voltage and current goes down.<br /> its very simple.<br />if you place your positive meter lead on the positive battery terminal, not cable end, and the negative on the solinoid terminal, not cable end, and crank the motor you should see less than .4 volts, preferably less than .2 and perfect would be 0V.do the same for the negative cable.<br /> from the batt post on the solinoid to the starter post you should see less than .2V again 0 would be perfect. from the batt term,not cable to the starter post,not cable you should see less than .7v while cranking here again 0V would be perfect.<br />the YU-34898 shunt from yamaha coupled with a DMM can quickly tell the current draw while cranking.<br /> if your dealer does not have it or does not know how to use it have them call their district training facility.
