Kawasaki Ninja ZX Forum banner
1 - 17 of 17 Posts

·
Registered
Joined
·
954 Posts
Discussion Starter · #1 ·
I have this problem that whenever I ride the battery drains to the point of barely being able to turn the engine over. I checked the alternator output per the Clymer manual and at 2,000 RPM it's pumping out something like 14.2v. Ideas? 1993 ZX750L
 

·
Registered
1993 Zx-7 L Model, 2006 ZX-10R
Joined
·
3,588 Posts
I have this problem that whenever I ride the battery drains to the point of barely being able to turn the engine over. I checked the alternator output per the Clymer manual and at 2,000 RPM it's pumping out something like 14.2v. Ideas? 1993 ZX750L
I had to redo the connector for the alternator on the harness and on the alternator itself. It likes to push a lot of current and the stock weather pack eventually gives way. I've only had mine last between 30k - 40k miles. After repairing the connection, it's good as new.
 

·
Registered
Joined
·
79 Posts
If u let it sit and cool off does it start fine? Or does it stay dead? Test the stator a/c output and the reg/rec d/c output (at the battery). Also test it when its cold and hot. Heat kills electronics like nothing else does.


Just had this problem on my buddy's M8 Street Bob and a customer's concours 14 a few years ago. The battery is in great shape, holds a charge and cranks right up every time. Passes every known test. But when u go ride it, it wont crank the engine if u shut it off for 2 minutes. Took a lot of head scratching to figure out the battery was growing slightly in the heat. Just enough that itd lose interior connection and wouldnt get any voltage to the bikes. Very frustrating problem. Only way to figure that 1 out is replace the battery and see if it still does it. But thats after every other test fails to find a problem
 

·
Registered
Joined
·
954 Posts
Discussion Starter · #5 ·
If it cools off for an hour or so it will start up after i charge the battery. A 15 minute ride will drain the battery to the point of it having maybe ten seconds of cranking time. Then it dies completely. How do you check the a/c stator output? As mentioned, d/c at battery is around 14.2v when cold and warm. Never tested it at after a ride however.
 

·
Registered
1993 Zx-7 L Model, 2006 ZX-10R
Joined
·
3,588 Posts
If it cools off for an hour or so it will start up after i charge the battery. A 15 minute ride will drain the battery to the point of it having maybe ten seconds of cranking time. Then it dies completely. How do you check the a/c stator output? As mentioned, d/c at battery is around 14.2v when cold and warm. Never tested it at after a ride however.
Replace battery. Report back
 
  • Like
Reactions: Therion

·
Registered
Joined
·
954 Posts
Discussion Starter · #7 ·
I got the bike up to full operating temp and tested the battery voltage and it was excessive, 15.2v. Then after shutting down the engine the battery was nearly drained as happened before. Before i spend the money on a new battery is there a way to verify the charging system is working properly as to not ruin a new battery?
 

·
Registered
Joined
·
397 Posts
15.2V is over charging the Battery and has Likely killed the one you have fitted, Fitting a new one without fixing the issue will kill that one sooner or later.
It's Likely the Regulator but there no longer available as a Genuine part.
 

·
Registered
Joined
·
954 Posts
Discussion Starter · #9 ·
Is there a way to test the regulator or just fit a new one hope for the best? Who sells after market ones for these bikes?
 

·
Registered
1993 Zx-7 L Model, 2006 ZX-10R
Joined
·
3,588 Posts
Is there a way to test the regulator or just fit a new one hope for the best? Who sells after market ones for these bikes?
Do you plan on rebuilding the alternator yourself? It's easier to replace the alternator as a whole. 91-95 zx7 (j/k/l/m) and 94-97 (b model) zx9 use the same one.
 
  • Like
Reactions: Therion

·
Registered
Joined
·
954 Posts
Discussion Starter · #11 ·
The entire alternator (labeled generator) unit is around $1,200 from Kawasaki. That is not happening. Look for a used one and hope for the best?
 

·
Registered
1993 Zx-7 L Model, 2006 ZX-10R
Joined
·
3,588 Posts
The entire alternator (labeled generator) unit is around $1,200 from Kawasaki. That is not happening. Look for a used one and hope for the best?
When you search for used, make sure the listing says it was pulled from a running bike. A video showing it was running or the alternator on a test bench showing it passed helps. Look for a high positive seller rating. I have 2 spares.
 
  • Like
Reactions: Therion

·
Registered
Joined
·
954 Posts
Discussion Starter · #14 ·
Do you know if the P model zx7 alternator is the same. Found a used one for cheap.
 

·
Registered
1993 Zx-7 L Model, 2006 ZX-10R
Joined
·
3,588 Posts

·
Registered
1993 Zx-7 L Model, 2006 ZX-10R
Joined
·
3,588 Posts
  • Like
Reactions: Therion
1 - 17 of 17 Posts
Top