Powerdynamo brings new ignition & light 
to your vintage motorcycle



Technical Help



Guide to identify Aermacchi Harley Davidson 4 stroke models
with respect to choosing the correct Powerdynamo system.

Experience shows that stating a model name or number alone will not be sufficient for reliable identification. This might have to do with different names and model numbers in different countries. Only way out is to identify what crankshaft and crankcase is used.

click onto pictures to enlarge them, click on system numbers to get to the respective info

crankcase fitting our systems 70 71 999 XYY


crankcase fitting our system 73 66 999 00


Note that there are 2 fastening holes 83mm apart for the dynamo which sits in a recess 97mm diameter. Oilseal is in the crankcase.   Note that there are 4 fastening screws for the magneto base and that oilseal is not on crankcase (but in magneto base).

With this casing goes a crank looking like the following. Note the female threading M7!   With this casing goes a crank looking like the following. Note the male threading M18 left!


Of this crankshaft type are 2 dimensions known, the 22 one (apparantly from 1969 onwards) this would be our 
system 70 71 999 x20.
  Seems to have been used around 1972.


... and the 17mm one (apparantly before 1969) this would be our 
system 70 71 999 x17.

  So far

no further versions found for this wide shaft magneto model

but one never knows ...

(if that is a consolation, there have been manufacturers who did use an even greater variety of generator systems - most of them have however have one thing in common: they are Italian!)

To add to the confusion, we do all systems both for single spark and for twin spark, as this is beeing demanded frequently.
In system numbers 70 71 999 XYY the X tells how many sparkplugs there are (1 or 2).
system 70 71 999 XYY will fit into the following models:
equipped with dynamo (crankcase view)
175 ala rossa 250 SS US-model 1967-68
175 ala bianca 350 SS US-model 1969-72 (20mm shaft)
250 ala verde -1970 350 SX US-model 1969-1972 (20mm shaft)
250 ala azzura 350 TV 1970-1971 (20mm shaft)
250 ala blu -1970 350 GT 1970-1971 (20mm shaft)
250 sprint C US-model -1967 ala d oro 250 (350) racing bike -1966
250 sprint H US-model -1967
system 73 66 999 00 will fit into the following models:
equipped with magneto (crankcase view)
Aermacchi 350 N/ Aermacchi 350 GTS
Aermacchi 350 TV Aermacchi 350 SX
Aermacchi 350 SS
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