Noise level after external alternator conversion

[wingandaprayer]

A conversion to an external alternator has been on the list for a while - mainly for the usual ease of repair / dependability reasons. We occasionally plug in a heated jacket. That's it for non stock electrical loads.

However - a question arises - since installing our Madstad adjustable windscreen system, I enjoy nearly zero deafening turbulence around the head and ears while riding any more - the "bike music" is now loud and clear...

How noisy are these alternators & belt drive whirring away at the 2x or 3x engine rpm they run at?

[clancyp]

I did mine last year and i hardly noticed any additional noise there is a whir sound but not a whine
like you would expect. I did spend alot of time making sure the belt was straight as possible but i
really don't even notice the noise. I am sure others will have more input. I have a stock windshield
and still get some buffeting so maybe that is masking the noise but i don't think so. It would be interesting
if someone had a db meter to check a stock against a conversion to see how much actual change there is.
Or you could be like the guy from Oklahoma who said ever time i hear a new noise in m car i turn the radio up.
LOL

[neoracer]

occasionally i hear some noise at idle but otherwise its not something i notice at speed,but since i have had it installed for 3+ yrs it may be something i've gotten used to,and even it there was some more noise i would not remove my poorboy conversion,the benefits with it are alot more plus's than w/o it
with all my accessories turned on and functioning i normally am only using approximately 22-25 amps,with heated clothing adds another 9 amps and cig lighter 8 amps,seldom does voltage go below 14.2 volts,except at a light it may drop to abut 13.8v

[Guest]

No change in noise level.

[Roleketu]

No noticeable noise from mine either.

[wingandaprayer]

Thank you for the responses.

[unionjack]

At idle and slightly above idle (standing still) I can hear a slight whirr, kind of like a turbo charger kicking in, but it is very slight, and certainly not noticeable when riding.

I remember noticing this noise when I first installed it, and played with it a little while it was new for a couple of weeks, but until this thread came up I hadn't noticed it in years.

Noisy? Definitely not! But it did sound slightly different that what I had been used to in a quiet garage. Now I don't notice it at all, it is just the way the bike is supposed to sound to me. Plus the engine itself is much much louder than anything the alternator will make, never mind the wind and road noises.

[admin]

With the 2.5" crank pulley there is very little noise, with the 4" crank pulley there is a noise not unlike a turbocharger spooling up when accelerating, not deeply intrusive yet noticable. Currently I run a 3.75" crank pulley and I am so accustomed to the sound of the alternator that I just about can't hear it anymore although it was very noticable at first, not noisy, just a new and different sound.