12 Volt = hotter spark

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12 Volt = hotter spark


Post by haggis » Fri Dec 06, 2002 4:13 am

would a 12 volt generator give a hotter spark if you retain the original coil...or would it just fry it!
Also, heard somewhere that a sportster generator will fit on my '50 without any drilling/tapping, anyone heard about this? thanks ...Haggis.

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Re: 12 Volt = hotter spark


Post by oldman » Fri Dec 06, 2002 4:26 am

I think its current you need to worry about. Its best to run a 12v gen with a 12v coil. Make sure its a points coil which I believe is rated at 5 ohms resistance. I made the mistake of buying an electronic ignition coil (3ohm) and using it with points on an otherwise stock FL. It will start up and run fine for about 10 min.
Then, when you are just starting to enjoy the road everything cuts out (if you have breakers) and you have to wait till your electrical system cools down. Then it will start and run for another 10 min. Anyway, 12v let you use common bulbs and battery which is a big plus.

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Re: 12 Volt = hotter spark


Post by 58flh » Sat Jul 31, 2010 1:31 pm

Whats-up beggis 58flh here, I was reading your post & ill tell you what i did, I took my genny apart-as luck would have it my buddy was with me. He is a V.W mechanic!, he looked at the stator & said it looks pretty much the same. So mon. after work he bought a stator out of a v.w., & sure enough the length was the same & the diameter where the brushes make contact was close enough! Now this came out of a 60s beetle, what i did was take my gennys outer-body & tried to fit it! it was a little tight when you spun it, so i chucked it up in a 3jaw chuck lathe ,a little fine valve-lapping compound & ran it very very slow! took about 6min. & had a perfect fit. did same for other end. I then cleaned up the brush contact area on the lathe, using a lite emerycloth, then you take your turning-bit & clean-out the spaces between the copper. Now this stator--commutator is a BOSH!, I also run a Bosh regulator mounted on top of genny. I have been running this set-up for 7yrs. know, the olny maintainance i do is change the brushes & clean it every other year!!! As far as i can see never a dead bat. also you know when your idleing at a redlight at night & twist the wick a little the light gets brighter, this dont happen anymore! My genny puts-out great, & the spark is a nice sharp crack! I dry fire 3 times hit the ig. & 1 kick it runs everytime, ofcourse if your timing is spot-on! another thing I use my pan year-round & there is no more generator trouble, 1 less thing to worry about!!! Hope I was of some help to you! stay safe 58flh

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