New "40 Amp" Alternator

Joined
Sep 10, 2011
Messages
2,211
Location
West Michigan
Bike
'98 ST1100
STOC #
8470
Received my new alternator today. Thanks again to John O. & Kiltman for the link :

http://www.ebay.com/itm/like/142538065683

The alternator is made in China, but looks like it's a quality unit.

On the Ebay website, the alternator was advertised s a 40 Amp alternator ( OEM rating, I believe ), but when I opened the box there was a test sheet inside and the spline has moly grease on it so it looks like it was actually tested. The test data is : 30 Amps @ 2K RPM, about 42 Amps @ 3K RPM and 54 Amps @ 6K RPM / 694 Watts.

I know the OEM rating is 40 Amps, but now I'm curious as to whether the OEM rating is at 3K RPM and an OEM alternator puts out more than 40 Amps at the higher RPM's ?

I'm happy to know this replacement alternator does.
 

kiltman

Site Supporter
Joined
Apr 27, 2013
Messages
3,280
Age
68
Location
Stratford, Ontario Canada
Bike
2002,ST1100ABS
STOC #
8826
I do hope it will give you good service. I know if I required a new alternator I would go this route. Good luck with the install.
cheers
 
Joined
Jun 3, 2006
Messages
3,513
Location
British Columbia
Bike
2021 RE Meteor 350
I know the OEM rating is 40 Amps, but now I'm curious as to whether the OEM rating is at 3K RPM and an OEM alternator puts out more than 40 Amps at the higher RPM's ?
Norm, on this site, reported a few years ago that he tested the output of a newly installed OEM alternator upgrade on a 1100 and found it was capable of ~ 55 Amps.
 
OP
OP
Jim Van
Joined
Sep 10, 2011
Messages
2,211
Location
West Michigan
Bike
'98 ST1100
STOC #
8470
Aha. Good to know, thanks.

John
I had a hunch it would be made in China - that's not a big problem for me. Almost all replacement and many OEM auto parts are made there now. Manufacturing standards in China have improved greatly in the last few years. Some plants are even ISO certified. About the only thing different is the cost of labor - same materials, same manufacturing processes.
 
Last edited:
Joined
Mar 13, 2012
Messages
5,047
Location
soCal
Bike
'97 ST1100
STOC #
687
Some plants are even ISO certified.
I'm not 100% sure about this, but isn't the idea behind ISO nothing more than a being able to replicate the same documented process over and over again? In other words, you could consistently produce a piece of junk, but as long as all your process was documented and rigidly followed, you're ISO certified?

not saying this part is junk, just asking about the ISO certification process.
 
Joined
Aug 10, 2015
Messages
2,029
Location
Fort Worth, Texas
Bike
91 ST1100/06 ST1300
I had a hunch it would be made in China - that's not a big problem for me. Almost all replacement and many OEM auto parts are made there now. Manufacturing standards in China have improved greatly in the last few years. Some plants are even ISO certified. About the only thing different is the cost of labor - same materials, same manufacturing processes.
Jim...yes, Chinese manufacturers are quite capable of making a quality product. That aside, if a customer provides a set of drawings/specifications for a product that was successfully manufactured by his domestic industry but also insists on a built-to cost, they will cut corners and make material substitutions that will enable them to make the product for that price. These unofficial design changes may not impact the product, but probably will.
As far as our alternator, time will tell.
 

Ron

Joined
Feb 5, 2005
Messages
1,665
Location
Orlando
Bike
ST1100s
STOC #
2432
hi will a 40 amp alternator bolt right up in a 1992 st ? they have different shapes.
Yes. Some other changes need to also be made. See the link below. Look around when you get there, there is a lot of information there.

http://www.st-riders.net/index.php?topic=901.0

I think there is a tool kit and video for that job. Maybe John Oo. is still tracking the kit.

Originally they were 40 ampers but somewhere along the way Honda found a different source. The new one looked and fit like the old ones but the output was upped into the 50's. I think the actual alternator is used on fork lifts, but a different end piece is used for Honda bikes.
 
Last edited:

ST1100Y

Site Supporter
Joined
Dec 4, 2012
Messages
4,981
Age
59
Location
Vienna, AuSTria
Bike
ST1100Y, ST1100R
STOC #
637
I too took the bait and ordered one of these:
https://www.ebay.at/itm/NEW-ALTERNATOR-FITS-HONDA-MOTORCYCLE-ST1100-1996-03-31100MAJG41-CGD38-1012111570/273046232349?ssPageName=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649
as "backup plan" to the overhauled, used 40A kit already in the shelf...
Even with P&P and import-VAT a LOT cheaper then most used ones over here (and lets not even start on the prices of new ones...)
The thing is brand new, clean, wrapped and came with a little "test sheet/certificate" (see pic)...

IMG_20180214_092952.jpg

I plan to throw it at the '94 ST once the temps raise again to bearable levels to a) ride there and b) work in the shed for longer periods...
 

ST1100Y

Site Supporter
Joined
Dec 4, 2012
Messages
4,981
Age
59
Location
Vienna, AuSTria
Bike
ST1100Y, ST1100R
STOC #
637
Yeah, after the graphics I'm a little concerned about idle charge & voltage... [emoji848]
Will take measurements on the OEM '00 ST first for comparison and to have a baseline...
OTOH: if that affordable Chinese alternator works and proofs reliable, a lot of the woes on this issue could be over...
It might actually be the OEM MFG, but since a patent or contract ran out, their just now enabled to sell publicly...

... transmitted from a CAT S60 thing ...
 
OP
OP
Jim Van
Joined
Sep 10, 2011
Messages
2,211
Location
West Michigan
Bike
'98 ST1100
STOC #
8470
I finally got my '98 ST1100 started after doing a bunch of work on it, including installing a new Chinese alternator.

So far, so good. Some feedback for Martin's ( ST1100Y ) concern about the idle charging voltage.

With my low beams and two smaller LED spots on, idling at 1,000 RPM the charging voltage is 14.1 volt and two green LED's are on on my Kuryakyn LED voltmeter.

Idling with all lights off ( I added a switch so I can turn off the low beams ) , the charging voltage is 14.4 volts and two green LED's are on on my Kuryakyn LED voltmeter.

Idling with the high beams on and two smaller LED spots and two really big LED spots on, the charging voltage is 13.7 volts and one green LED's is on on my Kuryakyn LED voltmeter performed.

This is about the same as my original OEM alternator.
 
Last edited:
Top Bottom