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ZX9R alternator
BenB - 16/11/11 at 08:36 AM

Does anyone know how many amps this puts out?
Its slightly OT but kind of BEC related
I've got the Denso alternator and I've searched for all the part numbers on it and nothing.
I'm guessing 25 amps at least as it's not tiny...
but does anyone know for sure?

MakeEverything - 16/11/11 at 08:52 AM

25A is tiny! Most spit out up to around 75A with the high power ones capable of over 100 iirc.

russbost - 16/11/11 at 09:02 AM

quote:
Originally posted by MakeEverything
25A is tiny! Most spit out up to around 75A with the high power ones capable of over 100 iirc.


Ehhh!!!! Never seen a bike alternator putting out that sort of power, I'm going from memory but almost certain the old ZX10 (which is going to be similar to the ZX9R) was 29 amps. It will certainly be in that sort of area, ie less than 30 more than 20. HTH

MakeEverything - 16/11/11 at 09:20 AM

quote:
Originally posted by russbost
quote:
Originally posted by MakeEverything
25A is tiny! Most spit out up to around 75A with the high power ones capable of over 100 iirc.


Ehhh!!!! Never seen a bike alternator putting out that sort of power, I'm going from memory but almost certain the old ZX10 (which is going to be similar to the ZX9R) was 29 amps. It will certainly be in that sort of area, ie less than 30 more than 20. HTH


Ive never seen an alternator on a bike, only generators inside the engine covers. I'm assuming the Denso alternator is a car unit?

BobM - 16/11/11 at 09:43 AM

2006-7 ZX10R is 31A according to Kawasaki manual so probably slightly less than that for a 9.

Hector.Brocklebank - 16/11/11 at 09:45 AM

quote:
Originally posted by MakeEverything
Ive never seen an alternator on a bike, only generators inside the engine covers. I'm assuming the Denso alternator is a car unit?


Eh that might be a No !! some bikes, and in my past experience its always been Kawasaki !!! that has used a alternator that looks like it was raided from their heavy engineering division.... see pic that is a ZX9 alternator





As far as i can remember it might be possible to have your original unit (or buy a spare) rewound to produce more and it being in a "car" style configuration it might be easier to find a specialist who rewinds alternators to take the job on to provide you with a higher output, or if your feeling brave you could try a rewind yourself.

[Edited on 16/11/2011 by Hector.Brocklebank]

BenB - 16/11/11 at 09:54 PM

Cool! Thanks for the info. 29A is fine for me It's true it's not a lightweight unit! I haven't stuck it on the scales but it's a good 4kg I reckon!

matt_gsxr - 16/11/11 at 10:23 PM

Not sure of the zx9r, but the carbed gsxr1100wp has an output of about 25amps. Later gsf1200 have slightly higher power 33Amp. These are both of the Denso design similar to that which you describe and pictured by 'hector'.

I rewired my alternator. Removing the internal regulator circuit (that limits the current to the spiny coil) and using one of those newer Mosfet rectifier/regulator units (FH014. I couldn't bench test the performance of the modification, but I haven't had the same charging problems that I had before (previously with lights on and EFI running I would flatten the battery after a long run). I made another few modifications (some LED lights, HID headlights [yes, I know...]).

Matt

matt_gsxr - 16/11/11 at 10:23 PM

Not sure of the zx9r, but the carbed gsxr1100wp has an output of about 25amps. Later gsf1200 have slightly higher power 33Amp. These are both of the Denso design similar to that which you describe and pictured by 'hector'.

I rewired my alternator. Removing the internal regulator circuit (that limits the current to the spiny coil) and using one of those newer Mosfet rectifier/regulator units (FH014. I couldn't bench test the performance of the modification, but I haven't had the same charging problems that I had before (previously with lights on and EFI running I would flatten the battery after a long run). I made another few modifications (some LED lights, HID headlights [yes, I know...]).

Matt