R/R or Voltage Troubleshooting Question

[Zero Knievel]

Okay, a weird thing happened on Saturday.  While heading home, my voltmeter showed my voltage spiking upwards to 18v.  Never did that before.

 

The voltmeter is pulling directly off the battery via a switched circuit thorough an auxiliary fuse block...so there's nothing else on the circuit to throw off the voltage reading from the battery.

 

Since shutting down wasn't an option, I pulled in the clutch and coasted for a few seconds (engine at idle).  That dropped the voltage down to normal, and eventually, the voltage seemed to go back to normal, and for the rest of the ride home, it never repeated and voltage remained consistent from 13.9v to 14.1v.

 

Back in 2012, my stator fried during a trip.  So, I had to replace both the stator and R/R (I had just replaced it, but I wasn't going to chance it wasn't damaged by the failed stator).  Per recommendations, I went with a MOSFET R/R from Rick's.  While almost 4 years have passed, I have hardly ridden the bike in those four years, so there's not much mileage on the parts.  When installing, I direct soldered the connections between the R/R and stator (per recommendations), and I heat shrinked each line to ensure no exposed wire.  I used the OEM connector on the side going to the wire harness with a liberal amount of dielectric grease and that rubber sealing tape to ensure no dirt/air/water could get to the connections.

 

***

 

Today, I tried to see if I could find any signs of failure.  I did the standard voltmeter test, and everything remained in spec...even running the motor up to 7K, the voltage never went above 14.1v.  Bike voltmeter and multi-meter remained in agreement.

 

I tore down the rear and got to the R/R, no evidence of physical or heat damage to the wires going to the stator.  I cut open the sealing tape and the OEM connector is clean and shows no evidence of physical or heat damage.  THE ONLY THING I saw was (after dismounting the R/R) was some white crud around the bolt holes.  While the mounting plate is painted, I can get a 12v reading from the battery to the frame at the mounting holes.

 

I want to start by presuming there is no R/R failure but another cause for this incident.  Since I've not been able to repeat it, I'd hate to do all the work to replace the R/R if something else caused it to happen.  After all, these parts have only seen 2,000 miles of riding since installation.  I did have a loose hot wire from my heated grips (found that Saturday morning), but the loose end was a clean shear, and I don't see how it would have made meaningful contact with anything to affect the battery voltage reading.

 

Do MOSFET R/R units discharge excess current to the frame/ground?  If so, would that white stuff possibly have caused a problem because there wasn't a good "ground?"

 

Are there other things that may have caused this to happen?  Other than run the voltage test several times over the next few days, I'd think an R/R failure would repeat itself.  Before going through the trouble to put in a new R/R, I'd like to verify the current one is defective.  If something else might have made it happen (e.g., a shorting wire), I can check to see if there's evidence of that first.

Edited May 15, 2016 by Aunt Sylvia

[redxxrdr]

Mike,

excellent description of the failure.

The mosfet regulator is still a shunt style.

It basically does the regulating by taking excess current to ground once the circuit voltage gets above a preset value.  

So the regulation is done internal to the R/r.  That is why it gets so hot.

The regulator is probably a high current zener diode.

 

So to your problem, I can't think of any failure other than the R/r that would give a higher output voltage.

But, your cluster mounted meter may have gotten a little goofy.

 

Also, the white stuff you describe could be heat transfer compound.  It is used to conduct heat from the electronic components to the heat sink. I have seen it ooz out if it gets real hot on non enclosed devices. But I have never seen it leak out of a potted circuit.

 

You are set up better than most with your volt meter.

I would ride it a bit more and see if the failure comes back before worrying too much about it.

If it comes back, pull in the clutch and let the revs drop to idle. I don't think that you can get more than 13vdc at idle. If you are still reading 19vdc, pull out your real VOM and compare meter voltages while it is broken.

[Zero Knievel]

Yeah, that seems to be the only thing I can do...ride the bike at every chance and see if it repeats.  I hate it when things act up then go back to normal.  I don't have the $$$ to spare to replace parts prophylacticly.  I'd like to confirm a malfunction before spending money on parts.

[The Krypt Keeper]

I would look at the tool pouch rubber band. 

 

Few posts involving r/r and stators lately.. Look and read

[Zero Knievel]

One of Rick's techs advised double checking the wiring on my voltmeter.  When their R/Rs fail, they fail.  They don't do something funny then go back to normal...at least I'd be their first case.

[redxxrdr]

Mike,

Of course I agree with the techs.

 

But do carry your regular meter with you for a while, and maybe a extra key to pull the seat while it's acting up.  Hopefully you will never see it again.

[superhawk996]

That white crud was probably aluminum oxidation and it won't conduct heat or electricity well at all.  Rick's stuff seems to be very hit & miss.

[The Krypt Keeper]

friends don't let friends buy Ricks

 

The only way you registered 18 volts at your battery is the simple fact that it was getting 18 volts sent to it..

 

It didn't decide to hold a little back and give it all back, it was all happy sitting at 14V when suddenly it was hit with 18v coming from.........

 

the R/R

 

 

[Zero Knievel]

14 hours ago, redxxrdr said:

Mike,

Of course I agree with the techs.

 

But do carry your regular meter with you for a while, and maybe a extra key to pull the seat while it's acting up.  Hopefully you will never see it again.

 

10 hours ago, The Krypt Keeper said:

friends don't let friends buy Ricks

 

I agree with both of you...to a point.

 

I have the better multimeter on the bike.  I static test the R/R every evening, and I'm riding the bike to/from work on the days I don't hit the gym.  If it happens again, the lock for the seat is already disabled so I can pull the seat off without needing to turn off the bike.

 

As far as Ricks' quality, they came highly recommended by people who had to replace R/Rs and stators.  I don't know who else I'd go to as OEM Honda parts are known to be prone to failure.

 

On the bright side, should it not happen again, I'm going to pack what I need to change a R/R in the field when I go to Cody.  I believe I saved my old R/R which was replaced as a precaution only (I still have the burned out stator in a box for some reason).  In a pinch, the odds are it would likely get me through the trip with no issues.  If Murphy's Law as it applies to motorcycle trips holds true, you never have a failure for a part you have the means to fix in the field.

[The Krypt Keeper]

See them other threads about these items in the garage section? 

 

Read them and take notes. 

 

There are other and better options than ricks. 

 

 

 

 

[Zero Knievel]

1 hour ago, The Krypt Keeper said:

There are other and better options than ricks.

 

You mean the Shindengen sh775 (Polaris)?

 

http://roadstercycle.com/index.htm 

(3rd one down from the top)

[The Krypt Keeper]

Series seems to be the cats meow, they require you to do the connectors but should serve you well. That one or the next one down. 

 

Which ever one will go for the XX. Double check before ordering or give them a call and ask. 

 

As for stators, 

There are also other places than ricks. 

 

 

[rc46]

As far as stator quality oem Honda is hard to beat.  Excess heat is what kills all electrical parts.  I did a write up on the sh775 reg install for those that are interested.  The series reg is the way to go as it cuts the output of the stator way down when it isn't needed.  Since the reg doesn't have to deal with very much excess current it doesn't run hot.(only warm to the touch).  Both the stator and reg should have longer lives due to lower heat levels.

[NoOne65]

I finally was able to do the mosfet RR from Jack at roadstercycles.com

[Zero Knievel]

Roadstercycle suggests the FH020AA as the SH775 has been known to have issues over 10K RPMs.

 

Input?

[superhawk996]

2 hours ago, Aunt Sylvia said:

SH775 has been known to have issues over 10K RPMs.

This effects you how?

[The Krypt Keeper]

Hahahaha, 

 

 

[redxxrdr]

I ordered the sh847aa,. I hope as the Suzuki part number. It is the next, next generation of the 775.

i haven't received it yet.  It was the latest one recommended on the Trumpet forums that Krypt Keeper posted.

 

 

[Zero Knievel]

Still haven't been able to reproduce the malfunction. 

 

This infuriates me because I despise mechanics who "swap" parts to diagnose an issue.  Ultimately, you end up paying for every unneeded part they install in an effort to root out the cause of your problem.

 

I could replace the R/R now as a safety measure, but that's $$$ going to a part that might not have failed at all (and ignoring the real cause for which I should still look).  I should have my prior R/R and enough kit to do a field replacement if it totally fails, and that should make me feel better, but I just wish I KNEW that the R/R has failed rather than this frustration of trying to get it to repeat itself so I can confirm it.  At this point, I can't eliminate the possibility of something glitching my voltmeter.