Alternator - generator replacement

Electrical issues
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Alternator - generator replacement


Post by aharp » Fri Apr 06, 2007 10:53 am

Description: Anyone seen or have experience with the alternator that runs in place of the generator or does someone have recommendations on a fairly bulletproof generator?

Post by aharp on Sept 21, 2006, 12:00pm

Anyone seen or have experience with the alternator that runs in place of the generator or does someone have recommendations on a fairly bulletproof generator? I haven't decided on a charging system yet since the bike won't be done till spring. The cases are generator style for a generator.

Post by caschnd1 on Sept 21, 2006, 3:01pm

I don't have any experience with the alternator kits. I've used the 12V generator w/ end cap generator from Cycle Electric. 25K miles (many in 105F+ temps) so far with no electrical problems at all.
My only complaint about the CE generator/regulator combo... UGLY! I wish they made one that looked closer to stock.


Post by 57pan on Sept 22, 2006, 5:27pm

I have an alternator on mine. It was on it when I got the bike so I don't have any way to compare it with a generator.
I'm not sure I would put an alternator on in place of a generator. They are pretty expensive, they don't look at all stock, and I think it is kind of noisy. Also, I don't think it is putting out the rated amperage - if I run with the headlight and spot lights on it will run the battery down, but I have never done any diagnostics to see if it is the alternator or the solid state regulator that is the problem.

Post by pzokes on Sept 24, 2006, 4:14am

I think that the alternators used in the conversion kits are from Kubota lawn tractors.
I prefer using a HD or Cycle Electric generator with a Frank's solid state Regulator.

Post by sleeper on Sept 24, 2006, 5:43am

those 'mini-alts' need shimmed same as a gen..
they are a 17 amp unit.. Early on they had problems w/shafts breaking.. But that was quite a while ago.. They have improved..
I don't like that the body spins w/motor.. If it was painted like a 'barbers pole' you might get dizzy watching it....

Post by DuoDave on Oct 13, 2006, 10:46pm

I have an alternator on my bike. I have had no real problems with it. I like it's compactness and simplicity. I have a couple of questions about it though.
57 pan - What sort of noise are you referring to? Mine makes a whirring sound when you kick the bike over, and when I'm out on the road, the alternator makes a scuffing sound, like a primary chain rubbing against the primary case.
Billy - What do you mean by saying the alternator needs shimmed? All you can change is the thickness of the gasket. I found mine quietened down quite a bit by fitting a thicker gasket.

Post by 57pan on Oct 17, 2006, 5:03pm


Yep... those are about the same noises that I hear. Sometimes it seems like I even hear a clunking noise coming from the alt. I've thought about removing the alt. and making a plate to block off the opening just to test it to see how much and which noises are actually from the alt.

Post by DuoDave on Oct 19, 2006, 1:30am

I did try taking the alternator off and had a quick spin up the road. I was surprised to find that my panhead motor is just about as mechanically quiet as an evo engine. When I put the alternator back on, the noises returned. I was going to try replacing the alternator shaft bearing, but it sounds like it won't make any difference. Don't bother making up a blanking plate unless you are paranoid about getting foreign objects in your gear case. Just disconnect from the rectifier and unbolt and remove the alternator. A quick run round the block will let you hear how your motor sounds and you won't get much oil thrown out.

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Re: Alternator - generator replacement


Post by 58flh » Mon Jan 02, 2012 1:50 pm

I know this is a old post---butI put a ALT. inplace of a genny on a sportster!--It worked great ,about 2 months later the guy shows up to my shop & what-else NOISE!---I did what Dave did unbolted the ALT. & he took it around the block--NO-NOISE!---SO I put new brushes in his old genny checked all output made it motor Then bolted a Bosch regulator on top of genny-Just like the set-up thats on my pan! WE fired it up ,polarized & continue to do output voltage at low & 2500RPM---The regulator although brand-new just needed a little tweaking on the low-output side/with lights on ofcoarse!--at idle slightly over 925RPM-Voltage going back to batt. was 13.9-(GOOD TO GO). another happy customer!-I tried to get the ALT from him ,but it was a no go!-But I can tell you guys there was alot of endplay in that thing!!!-I mean just turning it from end to end i would guesstimate -no shit 3/16 of play!-& I heard something loose in there!-didnt see it cant say what it was but to me I think it has to do with bearing clearences & the Temp. it is operating in! ONCE that gets squared away--SAD to say but there are going to be beautiful pans out there with ALTERNATORS!-HEY when does it stop being a PANHEAD? IM all for making shit run better but theres nothing wrong with the gennys 6 or 12VOLT!--ITS the guy who dont know how the circuit works & blames old technology!--I have rebuilt gennys older then these kids graduating from MIT or what -it !--they are at the age of computers! & comp. controlled motors!--TO me a computor does not belong in a car ,truck, or bike! THEY ran better before 1973! EPA is to BLAME here! THOSE bikes & cars cooked & didnt need 300 sensors to do it!--(Sorry for the rant guys but ALOT of us lived threw that era!!(dont now how) but we did! TRY telling a 22yearold that & just listen to what you get!--Half cant answer your ? the others blame it on pollution!(YOUNGER MINDS NEED TO KNOW WHATS-UP)--58flh :twisted:

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