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Discussion Starter · #1 · (Edited)
Well, it happened today.

My friend and I were riding and when we pulled up to the redlight, I noticed the 750 ACE that he was riding had a puff of smoke. Then it died. We pulled over to the side of the road and called my bro-in-law for his trailer.

Bike had no lights, no signs of life, but it DID have a strong burning smell. :roll:

We got it home and pulled the Regulator/rectifier. DEFINITELY smelly and, it had some black ooze coming out of a newly formed crack in the insulation. Also, the 30A fuse by the starter relay was blown.

We started by unhooking and checking all the connections. They all seemed intact, even the three-yellow wired one and the one that goes into the R/R with the green and red and three yellow wires. With the R/R disconnected, I replaced the fuse and turned on the switch. No smoke, but we had lights again!

I checked the three wire connector from the Stator. No grounding, and when at idle, they all had 17-18v and it jumped to 40-plus when I revved it up. When I put the R/R connection back on, instant "pop!" from the fuse. I wondered about the R/R having sufficient ground, so I checked the green wire with the multi-meter. Connecting to the red/white and green, it shows 12.78vDC, and the Ohm meter shows that the green wire has a good ground to the frame/engine. With all the evidence, I am lead to believe that the R/R went bad. There doesn't seem to be any issues with anything else until I plug it in.

We were planning on going to Bike Week tomorrow, so I'm going to see if we can locate a new R/R ASAP. I know there are upgrades, but I don't live next to the guy who makes them, so that will have to wait. My question is, does everyone think that the R/R can be the single issue? Anyone else have that individual issue? Like I said, I checked all the connectors and they're not burnt, corroded or anything. I made sure they were all connected completely also.

Another thing, doesn't the R/R usually get a dab of dielectric grease between it and the heat sink metal to help dissipate heat? Mine was dry.
 

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don't reconnect the RR

let me see if I have this right with the multimeter set to ac volts and the bike idling, if you connect to any two yellow wires you have 17 volts ac and when you increase the revs the voltage increases to 40 volts ac.. (you must repeat this test on each pair of yellow wires) also with the bike switched off and the meter set to ohms you have no resistance from each of the yellow wires to ground..

If what I have said is correct there is nothing wrong with your stator/ alternator and therefore all you have to do is replace the R/R and the fuse and the bike will be as good as new.

John.
 

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Discussion Starter · #3 ·
That is correct John. And confirms what I was thinking. Now, in burning up the midnight oil, I was also going to check if the local dealer had a Mosfet style R/R in stock. I was going to ask for the FH020AA unit like Roadstercycle uses. I can wire it, if I can get the R/R and connections. If the cycle shop has it, I'm good to go! Will see.

thanks!
 

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Since the alternator puts out AC voltage there must be diodes to change it to DC.
There are 3 positive and 3 negative diodes and if one of them shorts to ground, there is a lot of current to blow the fuse. And cause a lot of smoke from the unit frying internally.
 

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To answer the question '' My question is, does everyone think that the R/R can be the single issue?''

YES

I replaced a faulty R/R, with a stock unit, and am still riding :D

Enjoy Bike week,
D
 

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Discussion Starter · #6 ·
there is a lot of current to blow the fuse. And cause a lot of smoke from the unit frying internally.
Well, that pretty much sums up what happened. :lol:

I checked the R/R with a multi-meter and no matter how you post it, it's got continuity. EVERY connector is shorted to EVERY connector. IF there's diodes in there anymore, they're gelled into one heaping glob of wimpering goo! LOL!

I'll try to get a new R/R this A.M. and see if we can get on our way. film at eleven, as they say! Thanks for the input guys!

Everyone there agreed, that we're glad it happened so close to home, and not on the way to Daytona!
 

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If you have to buy a new r/r, I'd get a MOSFET r/r. They are so much better than the stock r/r. Lots of posts about them. It was one of the best things I have done for my VT1100-T.

ROD
 

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Discussion Starter · #9 ·
BUSY day today!!!!

We started off looking for a rectifier. Several shops later, my friend simply asked, "how much to rent a bike?" at the last shop we tried. They hashed out a deal and we were on the road by noon!

We decided to head up through the Ocala National Forest and across 40 to Ormond Beach. I can say that we were REAL glad it didn't poop out somewhere up there! Man, they 'bout need to pipe sunlight into that place! When the Gov't deems that there isn't much to harm up there and decides to put a bombing range in the middle of it, you KNOW that it's desolate.

We made it to Daytona and checked out downtown, the track and various other hotspots. Pretty cool stuff. Interestingly, one of the guys looked up in his computer and told me that the ONLY rectifier in central FL was in Daytona! Since everyone seems to price them right around $200, I decided to simply wait and send for the MOSFET unit. It's better, and it costs less!

My one-seventh of Bike Week went pretty well, all things considered!
 

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Since the alternator puts out AC voltage there must be diodes to change it to DC.
That would just about be the definition of a rectifier. On our bikes, the voltage regulator is built into the same unit so we call it a regulator/rectifier.

I checked the R/R with a multi-meter and no matter how you post it, it's got continuity. EVERY connector is shorted to EVERY connector.
That's not how you test a r/r. Check out this video.

FWIW, I wouldn't have bothered testing that r/r. This alone would have been enough for me to replace it: "We got it home and pulled the Regulator/rectifier. DEFINITELY smelly and, it had some black ooze coming out of a newly formed crack in the insulation."

Since everyone seems to price them right around $200, I decided to simply wait and send for the MOSFET unit. It's better, and it costs less!
The Shindengen from roadstercycle (or eBay) is NOT the only MOSFET r/r on the market. Electrosport sells one, too -- though I couldn't give you the model number off the top of my head. Don't know if it's any better or worse than the Shindengen but I'd bet it couldn't be any harder to fit onto the bike. Getting a Shindengen where I wanted it is the biggest reason I wish I had looked more closely at Electrosport's unit when I replaced my r/r.
 

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That would just about be the definition of a rectifier. On our bikes, the voltage regulator is built into the same unit so we call it a regulator/rectifier.



That's not how you test a r/r. Check out this video.

FWIW, I wouldn't have bothered testing that r/r. This alone would have been enough for me to replace it: "We got it home and pulled the Regulator/rectifier. DEFINITELY smelly and, it had some black ooze coming out of a newly formed crack in the insulation."



The Shindengen from roadstercycle (or eBay) is NOT the only MOSFET r/r on the market. Electrosport sells one, too -- though I couldn't give you the model number off the top of my head. Don't know if it's any better or worse than the Shindengen but I'd bet it couldn't be any harder to fit onto the bike. Getting a Shindengen where I wanted it is the biggest reason I wish I had looked more closely at Electrosport's unit when I replaced my r/r.
Electrosport doesn't claim they are mosfet type and I would think if they were they would say so. You can get OEM Yamaha sportbike R/R's but you have to cut and splice wires to use them.
 

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I've paid much less for R/R's. Motosports has some good ones for around 100. The ones they sell are about three times as big as the OEM but the bolt pattern still fits.
 

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Discussion Starter · #16 ·
Got it running again.

I ordered the DIY kit from Roadstercycle. They ARE larger than the original, so I removed the studs that were there originally and welded an additional 3.5"x3.5" piece of metal to the battery bracket so that I could mount it slightly lower than it was before. Since it was DIY, I was able to keep the wires as short as possible and could even re-use the stator wires with the new connector.

I checked everything out before installing the maxi-fuse. Check, check and double-check!

I fired it up and it was charging at a steady 14v. I took it for a spin and the benefits of a more constant voltage are evident. The lights don't dim at idle and when the turn signals are on, the rest of the lights don't flicker also. :cool:

All in all, a VERY good modification from OEM. Plus, the DIY kit is about $80 cheaper than what the OEM part cost! :wink:
 

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I switched to a Mosfet style regulator a few years ago and would never go back to the junk stock unit. Infact, when/if I purchase another Shadow, that will be the first mod I make on it. The Mosfet runs so much cooler and sends a lot more juice to the battery and is cheaper too.
When I did my swap, I bought a used Mosfet regulator off of a Yamaha R1 off Ebay to see how much difference it made and I'm still running it today.
Do yourself a favor and take the stock regulator out and throw it as far as you can!!
 

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Electrosport doesn't claim they are mosfet type and I would think if they were they would say so.
They do sell a MOSFET r/r. Know because I contacted them back when I was shopping for mine while working out replacing the stator. Had the info in e-mails that got lost in a fixed-disk crisis earlier this month. Think I told them they should make the MOSFET construction better known. Would probably have bought the Electrosport r/r if I had gotten my stator from them. Went with the Shindengen due to all the favorable reviews -- here and elsewhere -- when I got a brand-new-in-the-box Electrosport stator from a guy here.
 
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