Author Topic: SH775 Series Type RR on CB750K5  (Read 814 times)

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Offline Tom R

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SH775 Series Type RR on CB750K5
« on: December 01, 2022, 02:05:10 PM »
I realize these bikes are field controlled generators… and this type of RR is usually with a permanent magnet type rotor….
To me, right now, the biggest advantage I can see is that I have a sh775 and it’s much newer than the 1975 charging system. I’ve installed a couple of these on different bikes and have been pretty happy with the results so far.
If I bypassed the regulator and connected the white field wire directly to the ignition, it’d essentially act like a permanent magnet rotor… and I’d input the 3 yellow wires from the stator to the sh775 and output the pos and neg wires to the battery.
The way I understand it, because they’re not shunt type, the series type RRs wont stress the stator.
Would this be an upgrade, liability, or just newer?
« Last Edit: December 01, 2022, 03:28:31 PM by Tom R »
CB750K5 - Slowly putting back together.
GS1100LT - Nicely upgraded over the years.
CB400F - Production lightweight race bike.
Cl175k7 - Gp200 race bike.

Offline Tom R

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Re: SH775 Series Type RR on CB750K5
« Reply #1 on: December 07, 2022, 09:46:34 AM »
I probably don’t need a new regulator, but the rectifier is past its prime; and the Rick’s unit is $110….so I guess I’ll  play the Guinea pig on this one. My field coil and stator spec out good according to my multimeter, so I’m going to give it a try.
If anyone knows why this would be a bad idea, please chime in before it warms up in Chicago, haha.
CB750K5 - Slowly putting back together.
GS1100LT - Nicely upgraded over the years.
CB400F - Production lightweight race bike.
Cl175k7 - Gp200 race bike.

Offline Don R

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Re: SH775 Series Type RR on CB750K5
« Reply #2 on: December 11, 2022, 10:46:34 AM »
 I've read the old windings don't like to be stressed beyond the original spec. That said, I'm only a wiring guy and not an electrical theory guy.
  I always experienced using a less than optimal part because you already have it ends up costing me more and taking longer to get good results. If you proceed, keep us posted.   
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Offline grcamna2

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Re: SH775 Series Type RR on CB750K5
« Reply #3 on: December 11, 2022, 11:38:55 AM »
I've installed an SH775 'Series' MOSFET style reg/rect. on a Suzuki GS450T(permanent magnet rotor)and it worked great;I first heard about this on thegsresources.com Suzuki forum which has lots of write-up/threads on the SH775.
I appreciate your thread on this and will be following.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
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