ST1300 Alternator Output

[Andrew Shadow]

In another thread flyfisher posted;

BTW, all 1300s have the same output alternator

to which I replied;

2003 to 2007 model years have a 0.742 KW alternator.
Post 2007 model years have a 0.675 KW alternator.

I took the above information from the Honda ST1300 service manual taking this to mean that they had different outputs as listed to which I received the below response;

They didn't downsize the alternator, just the published capacity.
31100-MCS-003, same part number for every ST1300, even the ABS and police models.

This response confuses me. What does this mean? Do all ST1300 alternators have the same output alternator or not? If they do is it .742 KW (Appr. 62 amp.) or are they all .675 KW (Appr. 56 amp.).
Why does the manual list them as having different outputs if they have the same part number and are all the same?

It isn't of any real relevance as it has much more capacity then I need but it made me curious- inquiring minds......................

 

[T_C]

I think the original output spec was rated at an engine speed of 5k (rpm), and as an engine speed (hence) alternator speed will dictate maximum output; 5,000 rpm is well above the legal speed limit while in 5th gear for the vast majority of the US, they were probably trying to head off a potential frivolous lawsuit.

 

[dduelin]

Best output cold and minimum realistic output at operating temperature. It's hot in the vee.

 

[Don B]

Another plausible explanation that occurs to me, after having been a tech writer for more years than I care to remember is that an engineer provided a spec sheet with an incorrect spec for the alternator to the writer(s) and it got published that way, was subsequently discovered and corrected in the later specs. Not saying that's what happened here, but it's a very plausible possibility.

 

[Andrew Shadow]

I think the original output spec was rated at an engine speed of 5k (rpm)

The service manual lists both output capacities at 5, 000 RPM.

an engineer provided a spec sheet with an incorrect spec for the alternator to the writer(s) and it got published that way, was subsequently discovered and corrected in the later specs.

Wouldn't they then just change the spec to which ever of the two is correct rather than introducing two different specs for different model year break-points?