Magna Owners Of Texas

Public Forums => The Garage => Topic started by: cruiserlover on May 02, 2017, 05:57:15 PM

Title: Question about my new 95 magna
Post by: cruiserlover on May 02, 2017, 05:57:15 PM
I just got my beautiful blue and black 95 750 a few days ago.When I looked up model history the 95 did not come in those color combinations. The former owner put a device on the handlebar that is some sort of a voltmeter.It has a litup numerical reading when the key is on.he and i went opposite ways, he lives in another town.This was his 8th magna.I traded a goldwing for it.Why would one of those monitors be necessary and what does it do.I went riding while ago.Absolute beautiful day.
Title: Re: Question about my new 95 magna
Post by: lragan on May 02, 2017, 06:16:31 PM
The most common failure in the 3rd gen Magnas is the regulator/rectifier.  If you do a search you will find more information on this problem than you ever wanted to know about, so I won't go into it here.  The voltmeter is a way to give a warning that you are no longer charging the battery.  With 3500 or more RPM, you should read 14 volts or slightly more.  I have two '96 Magnas and don't have a voltmeter.  I have replaced the regulator/rectifier modules with more modern designs from aftermarket, and relocated them from the bottom of the battery box where they get too hot. 
Title: Re: Question about my new 95 magna
Post by: hootmon on May 02, 2017, 06:39:02 PM
What Lawrence said.. Regulators can go bad by under voltage (Most common) or over voltage..
I won't own a Magna without one going forward..
Title: Re: Question about my new 95 magna
Post by: cruiserlover on May 02, 2017, 08:29:45 PM
Quote from: hootmon on May 02, 2017, 06:39:02 PM
What Lawrence said.. Regulators can go bad by under voltage (Most common) or over voltage..
I won't own a Magna without one going forward..

I have read probably 25 posts about this problem.What more modern component are you recommending,where do I get it.riks?
Title: Re: Question about my new 95 magna
Post by: LIMagna on May 03, 2017, 07:14:57 AM
Something like this ...

http://www.magnaownersoftexas.com/forums/index.php/topic,6128.msg58222.html#msg58222 (http://www.magnaownersoftexas.com/forums/index.php/topic,6128.msg58222.html#msg58222)
Title: Re: Question about my new 95 magna
Post by: ttooee on May 03, 2017, 09:12:50 AM
This problem is a common issue with all motorcycles until motorcycle manufactures decide to get away from the permanent magnets generator/alternator design.
To my knowledge, there are no modern component replacement. All REC/REG will have diodes and that is what will fail.
Best and simplest is to monitor the battery condition with a voltmeter which you all ready have on your bike and to carry a spare on long trip.
Title: Re: Question about my new 95 magna
Post by: cruiserlover on May 03, 2017, 09:15:52 AM
thanks guys.
Title: Re: Question about my new 95 magna
Post by: lragan on May 04, 2017, 09:08:59 AM
I disagree with the post that there are no improved R/R for the Magna.  The regulator function works by shunting the alternator current to ground for a portion of the cycle to maintain the required voltage.  The OEM design used bipolar transistors for this function.  The voltage drop across modern MOS transistors is much lower, reducing the dissipated power and thus the temperature rise.  Many of them are not expensive.  I bought one a few years ago for $30. 
Title: Re: Question about my new 95 magna
Post by: cruiserlover on May 04, 2017, 02:36:02 PM
Quote from: lragan on May 04, 2017, 09:08:59 AM
I disagree with the post that there are no improved R/R for the Magna.  The regulator function works by shunting the alternator current to ground for a portion of the cycle to maintain the required voltage.  The OEM design used bipolar transistors for this function.  The voltage drop across modern MOS transistors is much lower, reducing the dissipated power and thus the temperature rise.  Many of them are not expensive.  I bought one a few years ago for $30.

do you remember the brand,part number or anything like that?
Title: Re: Question about my new 95 magna
Post by: ttooee on May 04, 2017, 06:15:39 PM
In Dec 2014 I bought two different aftermarket R/R. One more expensive and the second I think was about $15 of the internet. I installed the cheap R/R first and still running with it about 8k plus miles now. Keeping the expensive one as backup (kind of backward huh?)
OK, the MOS transistors make the regulator half better, but what going to fail first? Diodes or transistors? My experience with automotive regulators on the '70 and '80 it almost all the time the diodes that fail first.
Here is the expensive R/R - ElectroSport High Performance Regulator model ESR530.
Title: Re: Question about my new 95 magna
Post by: ttooee on May 04, 2017, 06:28:13 PM
It's just my opinion, but I like OEM R/R better than aftermarket. If money is not a factor, I would go for the Honda R/R.
Title: Re: Question about my new 95 magna
Post by: lragan on May 04, 2017, 09:50:21 PM
Quote from: ttooee on May 04, 2017, 06:15:39 PM
In Dec 2014 I bought two different aftermarket R/R. One more expensive and the second I think was about $15 of the internet. I installed the cheap R/R first and still running with it about 8k plus miles now. Keeping the expensive one as backup (kind of backward huh?)
OK, the MOS transistors make the regulator half better, but what going to fail first? Diodes or transistors? My experience with automotive regulators on the '70 and '80 it almost all the time the diodes that fail first.
Here is the expensive R/R - ElectroSport High Performance Regulator model ESR530.
/quote]

So, does '70 and '80 mean 1970's and 1980's?  If so, let me point out that there were no power MOS devices during those decades.  Most shunt regulator circuits used Triacs.  In automotive alternators, there were six diodes, and the feedback mechanism was entirely different.
Title: Re: Question about my new 95 magna
Post by: ttooee on May 05, 2017, 12:59:01 PM
On the regulator side of the circuit is much improved, great.
What about the rectifier circuit? Is there a rectifier circuit on these units anymore? What do they use for rectifying circuit?
Title: Re: Question about my new 95 magna
Post by: lragan on May 06, 2017, 04:55:46 PM
the shop manual has a schematic