TOPIC:

By Nessism: Martin, there are two different type of newer type Shindengen R/R's: the MOSFET type that start with a FH prefix and the better SERIES type like the SH775. They both look the same but the SH775 is superior....

Thanks. I looked into a mosfet a couple of years ago & found some good how-tos on a Ninja 500 site, but I don't have anything in my notes about the SH being better than the FH. All I can remember is that the mosfet is supposed to be better & runs much cooler than the stock-type KZ & EX500 voltage regulator.

Nessism wrote: No disrespect guys but I have no idea why anyone would buy a shunting R/R when a superior SERIES type can be had for $45 shipped.

I haven't needed one for a long time. The originals lasted 25 to 35 years. Since I replaced a couple with ones from mid 2000's, I may not need one until 2030 at the earliest, and that's assuming they didn't approve longevity.

I'd be willing to try one for testing, but based on Shindengen's own website, I'm not convinced the series architecture they chose, is for me. They are using 6 SCR's in place of the 6 diodes. That is actually a design I've seen floated around for many years.

Yes, a series-pass reg/rec has the advantage of wasting less crank power, and running the stator cooler at higher RPMs, but it is not without possible drawbacks, especially at lower to mid RPMs.

Unless they have somehow found SCR's without all of the old drawbacks (which is possible), here are at least two potential problems:

First, SCR's, being active devices, are not quite as reliable as diodes, though they are among the most reliable industrial devices (I believe Crydom still uses them over everything when it comes to handling larger currents). And they are, historically, more reliable than MOSFETS. In the original shunting configuration the SCR's were effectively out of the circuit when the system voltage was low, like at idle, or right after a cold start. They would only become active at higher RPMs, and when they did become active, they may only be shunting for part of a cycle. (They turn off automatically when the phase reverses.) So if you spend a lot of time at slower speeds and idling, as in stuck in traffic, the SCR's will be active almost continuously. Whereas in the shunting config, they would almost never be active.

Second, and this is more of the issue, SCR's, typically/historically, have a higher forward voltage drop than simple diodes, when they are expected to handle the current of a typical KZ. What this means is, right when the bike needs to make full use of the available alternator power, as in low RPM or idling, (because the alternator power is low at low RPM), the series SCR's would be dropping more voltage than diodes would. This means, with a SCR-based series-pass reg/rec, the RPM at which the bike starts to charge the battery would be higher than that of the conventional shunt type reg/rec. For me, this would be greatly detrimental to my batteryless bike. While going batteryless is pretty rare on Kz's, this same issue would also exacerbate problems if anyone is already having charging issues using a Dyna S ignition. They use a lot of power at idle, and that would be when the series-pass voltage drop would be happening.

When I was designing my own KZ reg/rec, the series idea crossed my mind, but the low RPM output loss with the SCR's I had, would not be acceptable for that design, so I went with a conventional design. That was probably over 10 years ago.

But I'm perfectly willing to accept that they overcame these issues. If you have a link to where someone actually measured the instantaneous forward voltage drop using a scope, on the positive side SCR's and the negative side SCR's, that would be great. A simpler test, could also be done. Using a constant, high-load, running a bike at idle and measuring the output of the reg/rec and comparing the output to a new, but conventional, shunt-type reg/rec, would reveal any difference.

Most of that was over my head but it seems you are saying that if you do more high rev riding series R/Rs are good. If you do lower rev riding shunt or MOSSFET R/Rs [whatever that means, I'll Google it some day] are better.

More than half my riding is on the highway or canyon carving so the series type is a good match then?

If it isn't at least the FH-whatever R/R is now just plug and play.

GPzMOD750 wrote: Most of that was over my head but it seems you are saying that if you do more high rev riding series R/Rs are good. If you do lower rev riding shunt or MOSSFET R/Rs [whatever that means, I'll Google it some day] are better.

That is a fair summation of what I posted, as long as the original premise of my concern holds up. There does not seem to be any data either way, so can't really make a solid conclusion. I am only going by the simplified schematics on Shindengen's site, and personal experience tinkering and designing/building regulators.

Based on their description, the shunt-type using MOSFET's was designed specifically to address the voltage loss issue I was describing. The series-type still uses SCR's.

They also, apparently, still produce the tried and true, conventional, shunting-SCR type with standard diode rectifier.

I can't comment about the efficiency of the series SH775 units at low power output levels (low rpm's) but I can say that my bike, with fresh stator and SH775, gets up to voltage easily at low rpm's.

I've spent a good bit of time working on Suzuki GS bikes over the last 10 years and those bikes burn up stators quite easily. I'm not certain but I think their charging systems are more powerful than the typical Kawasaki, so there is more extra current to shunt back, thus the stators are more prone to failure. Many of the aftermarket stators on the market are made to create extra current also. While this may seem like a good thing it's not good in terms of assuring the stator lives a long life.

I have also heard of GS's burning up stators, and sometimes regulators as well, at least more so than Kz's, so it may indeed be that the Gs stators have output that is a little high. If that's the case, a series reg/rec would be the answer.

Quick update - Thanks to your tips, Through process of elimination I believe I am beginning to narrow down possible problems in my bike's electrical and charging system. Some of this is not directly electrical related - and for that I apologize. This is my quest to provide the bare necessities to the old girl (air, fuel, spark and compression) What follows below is my rambling, somewhat coherent findings and questions. Thanks for tuning in.

1) I changed the spark plugs over the weekend and it seemed to make a world of difference in the idle and mid range RPM riding, for a time. 1/4 spark plugs showed signs of running very rich. I have been messing with the main idle adjust screw A LOT, in attempts to get the bike started up. I want to find a good spot for the screw, (RPM idle adjust) and leave it. What RPM range is a good spot to start it at? When I pull to a stop light, what should the RPM's read? Currently I've around 600-900 RPMS at start and ~1500 at stop light.

2) I received a R/R from a 2009 Ninja Ex500 (Credit to Martin CSR) and installed it last night on my bike. Looked like one solid red wire on my bike was matched up with a red/white wire, and a black was matched up with a black / yellow striped. Only difference from original. Same MFG (Shindegen) and part number. (Also, what do the T 8.9, T 8.2 or T 2.4. numbers mean?) I just plugged it in, bolted it on and went for it. I had taken my battery to my local advance auto, to have them charge it for a while. It was at 13.6 when I installed it on the, with the new R/R. Still would not turn over. It cranks, but wouldn't start without me throwing it on my trickle charger in the garage for ~10 minutes. After that, Bike ran alright, not great. Hesitant to start and hold an idle, Seemed to lack acceleration when I finally got on the road. So the battery is good, and the R/R is good, but I am still experiencing a charging issue/ Battery drain.

3) Another couple things I've noticed: "head lamp" idiot light on instrument cluster comes on when I turn the key, but disappears intermittently.
Also, my Headlamp, front turn signals and instrument cluster lights all suffer from dimming when I engage either brakes. This is not surprising, but I'm wondering if these are answers to a question I haven't asked yet?

4) What is the significance of the 6 SCR instead of 6 diode

5) Not electrical, but I finally found a gas station with Ethanol Free 87 Octane gas - I've read that the motor in my bike actually seems to operate better on the lower octane, due to a lower compression ratio. Compared with 91 octane which I've been running as it was the only ethanol free I've been able to find until last night. What experience do you guys have with the octane grades and performance/ reliability/ etc. ??

6) Not sure what my next course of action should be. It idles kinda rough, when I finally get it started. Doesn't seem to perform well. Mechanic took a quick peek and said perhaps there's an intake leak and to replace the carb boots. Makes sense. Are these the airbox hoses from the carbs to airbox? www.z1enterprises.com/product/11015-057-K

Or the carb "holders" ?
www.z1enterprises.com/product/16065-1014X4
www.z1enterprises.com/product/IMK16065-1014X4

How involved of a job is replacing the carb "boots?" If any idiot can do it I'll buy them and do it this weekend.

Also thinking maybe time to replace airbox filter. I'm probably going to replace the fuses soon as well. Somebody mentioned they brake easily from vibrations and should probably all be replaced annually anyhow.

7) I want to say thank you again for everyone's input. It's been a Humbling, frustrating, and really fun/ rewarding experience so far with this bike but I feel I am learning alot - and I have all of you to thank. I know this bike has potential and I'm determined to bring it out.

87 octane should work well in your bike. 91 octane is fine but is a waste of money since your bike doesn't need 91. Ethanol free fuel is good. 10% ethanol is no big issue mind you assuming you are using the bike regularly and don't let the fuel go stagnant in the tank. That's where the ethanol stuff really sucks; it coagulates much faster than 100% gasoline and can cause system corrosion because the ethanol absorbs moisture in the air.

BTW, if your engine turns over slowly that suggests a weak battery. You can't judge a battery's cranking ability by looking at no-load voltage. A load test is needed.

Load test yielded no higher than 12.5 voltage.

Before this, my meter would cycle between .5v and low 12's,

To reiterate - One night I left the key in ignition and lights on after switching off the bike for ~10 minutes. Bike's lights worked but would not turn over, eventually dimming lights. Bike would not pop start either. This is where all my problems have stemmed from. I have not been able to get the bike starting reliably since.

Dude at Advance said battery is strong and should not be the issue (Same battery which was in bike when it died on me) . Battery is two months old, perhaps I just haven't charged it enough/ correctly?

#2. credit goes to Loudhvx as I got the idea from him.

#2. a simple load test is to charge the battery, then turn on the headlight hi-beam (engine off) & check the voltage. A good battery will go from 12.6+ to about 12.2 VDC. If it drops a little below 12 VDC, the battery may need replacing. below 11 VDC, the battery is probably shot. Ctek US 0.8 smart charger & VC97 digital multimeter.

#1. Are you using the choke to start the bike? depending upon the ambient temps, you should have to use 1/2 to full choke when the bike is cold & adjust the choke to keep the rpms below 2000 during warmup (1500 seems good to me).
After warmup, it should idle around 1000-1200 rpms. I follow the owner's manual guidelines. the bike should operate within those parameters. or fairly close since it is old.

#5. I think a reason to use higher octane would be to avoid pinging. It may run fine on 87 under most conditions, but there may be times when you hammer the throttle that 91 or 93 would be beneficial. not necessarily so, but possibly.

#2 Thanks Loudhvx!

#2 The battery has read below 11, but not last night. I have a warranty on it - at this point, I should just replace it and get a brand new one to eliminate that variable.

#3 Indeed, always starting on full choke, Petcock on prime and a quick squirt with the throttle. Even after sitting on the trickle charger for ~24 hours, it would not start. This is what led me to bring the battery to advance and get a real charge into it.

I don't think the 550 carburetors have an accelerator pump, so twisting the throttle doesn't squirt any fuel.
When starting a cold bike, you shouldn't have to touch the throttle, but do use the choke.
When it's fully warmed up, you don't use the choke, but open the throttle a tad. unless the om says otherwise.

ps: see the Starting the Engine section of the owner's manual.