Alternator amperages?

[Guest]

I installed an alternator on my 88 katana 600, the alternator was from a 86 gsxr 750, now the wire connection from alternator and bike harness gets hot and you can see light smoke, after 30 on bike running, across the battery i'm getting 14 volts. Are all alternators the same, or do they have different amps setting.

[Black_peter]

They have different capacities based on what they are going in. A gold wing alternator for example could run a good sized car's electrical system.

More likely is that you may have wired it up wrong??
Or if you just pluged it in then maybe the wireing is not the same between the two models..

[The CyberPoet]

The GSXR alternator does not normally put out as much power as the Katana alternator at low RPM's, and may be strained by your bike (esp. if there is a grounding fault somewhere).

Key differences:
The Katana alternator is somewhat heavier, has more windings, and will normally result in a positive charging state even at idle (at least on the 98+ models; I think the same applies to the pre-98 models), where the alternator is putting out more power than the bike is consuming in stock form (given no electrical add-ons). This is appropriate design for a bike whose primary design purpose is a sports-tourer and commuter.
The GSXR alternator is minimized for "race wieght" requirements and like most race-bike alternators, is designed to put out enough power to charge the system at and above about 4.5k RPM. Below that RPM level, the system is usually working in a net-loss (taking excess off the battery rather than charging it).

KNOW THIS:
Firms that wind alternators for cars in-house can usually rewind a motorcycle alternator as well if needed. This is often cheaper than buying a replacement, but be sure to bring replacement bearings with you, as they probably won't have the right size and rated bearings for a motorcycle (higher RPM's).
The over-charge capacity of a Katana is around 35% normally, meaning the charging system should be able to put out 35% more than the draw against the bike at 5k RPM given a stock bike running on high-beams. Obviously, since the 98+ draws more power (dual headlights), it has to have a larger output in general.
Suzuki's alternators very rarely go bad; usually it's the IC rectifier pack that goes, and more rarely, the bearings for the shaft.

cheers
=-= The CyberPoet

[md86]

I think the same applies to the pre-98 models

Yup .