Following the lead of many of you who have been kind enough to pave the way, I'm almost finished with the installation of the 3.5 inch "Poorboy" conversion. I read and printed out most of your postings relative to this procedure, and taking a little from everyone who has taken the time to post pictures and explain their work, I thought I'd offer some pictures of my progress so far. As others have noted, It took this novice wrench turner at least two full weekends of trimming, fitting, and re-trimming and re-fitting. It seems that patience was the key. I didn't want to cut too much at once, and I wanted to keep things a neat and tight as possible so I took my time. My goal was to keep this as close and tight as possible so anyone who's not looking wouldn't notice that Nippondenso powerhouse tucked inside I haven't found anyone who has posted close ups of the trimming of the plastic cowl that's necessary to fit this alternator, so I thought I'd try. I believe I got this as close as possible to the carburetors and heat shield as I could.



Used the Gates 25030310 - 31.68 inch 3 Groove Micro V belt. The next size up would have been 32.915 inches, and I was concerned the alternator would hit the fairing.



While trimming the plastic cowling, go slow and don't cut too much at once. It gets thin at the bottom fairing bolt holder, and you want to refrain from removing any more than necessary to clear the alternator.



Following "Poorboys" suggestion or option for gaining space with the radiator fan, I removed the factory bolts, and replaced them with M5-80-20 and 30 bolts. The top one is about an inch long, and the lower two are about 1.5 inches.



Again, following others who suggested re-mounting the horn close, I was able to tuck it in behind the alternator, facing slightly outward. It's a tight fit, but a little bending of the bracket and drilling a hole in the fairing bracket, it's seems to clear a test fitting of the lower fairing. This horn is a replacement for the factory one that was dead.. You never discover this stuff till you have it mounted. Aftermarket horn from "Carquest" # CPF 40110 was $16.00 plus tax. OEM replacement was listed on one site for around $45.00. It's seems very happy tucked behind that alternator



I placed the alternator as close to the front heat shield as possible. I used the smallest belt I could and still be able to remove it.


pretty close..

Great post! Especially the pic of the lower cowl. I did something similar to mine but never thought about putting a picture out there for all to see. Looks like you have a pretty clean and shiny bike there to boot.

Thanks Gunny! I spent a little time this winter sanding/polishing the aluminum. Not as much time as I spent with the "Brasso on those belt bucklets at P.I. in 73, but this time I'm hoping the shine lasts a little longer!!

I hear ya! Same Brasso I used in San Diego in '79. Hours of finger numbing work for 15 minutes of utility. All it took was one touch with dirty fingers and you had to do it all over again. I remember putting socks on my hands to fasten the belt prior to final inspection so that I wouldn't get fingerprints on the buckle. Never once saw the DI's shining their brass, of course they didn't let us know that they were all wearing the anodized stuff.

I may try that buffing thing on my forks this winter. My timing belt covers were chrome, but they were really pitted so I ground off the chrome, sanded them down and painted them metallic grey, using engine type paint in rattle cans. It worked okay, but I think the buffed out covers look real sharp.

Excellent post, thank you.

Can you hear any alt. whine under load being up that high ?

Hi Scott, I'm waiting for 8 gauge wire and the 50 amp breaker I ordered so I haven't put this under any load yet. I doubled up a couple 10 gauge wires, and rigged a 30 amp blade fuse just to see it work, however I only ran it long enough to see that nothing was rubbing or hitting after the install. I have all the plastic off it now, so I'm not really sure what I'm going to hear noise wise from the alternator. From what I've read from others who have completed this conversion, I don't recall anyone complaining about noise. I guess time will tell.

I can indeed hear a little alternator whine/belt and pulley whine, but it is not bad at all, in fact maybe even a little cooler sound when mixed in with the engine noises.
Certainly it is not an issue, and you would be had pressed to notice it if you didn't know what the sound of the bike was like without it.

Great post!

What a nice clean looking install, not to mention the bike too. Do you guys figure there is any cost as in hp going this way. I assume the stock altinator is still installed. Is it also inevitable that my altenator will fail on my 86 Aspincade? Is there a mileage or age thing to go buy. My bike only has 26 thousand miles on it and is very clean. The guy I bought it off of had a plug under the left side cover removed and hard wired in a preventative measure. Thats what he told me anyway. What kind of accessories can I run off the stock electrical system?

Thanks for the reply. It took some time to sand the corrosion off the aluminum. started with 150 grit and worked up to 600 grit wet. Then the "sears" brand polishing rouge on a vertical buffing wheel, and finally buffing with aluminum polish. It was a little frightening at first, took a lot of time, but I was pleased with the result.

If you take some time Ultra, and read over the many posts relative to Stators and Alternators, you may reach the same conclusion I did, and convert. It seems everyone I've talked to say that eventually the stator fails. Some have said in little as 12,000 miles, and some say they are reaching six figures on the odometer. Maybe one of the real mechanics will pipe in and offer an opinion regarding the limit of accessories with the stock stator!

"I haven't found anyone who has posted close ups of the trimming of the plastic cowl that's necessary to fit this alternator, so I thought I'd try. I believe I got this as close as possible to the carburetors and heat shield as I could. "

Unless they have been removed my pictures are buried somewhere.

I wasnt happy with the meagre amount of plastic left after cutting for the alternator so I made a metal piece.

Yes, there is. Anything driven off the crank is going to require hp. The average auto alternator requires anywhere from 10-25 hp depending on the load. Fortunately our bike's don't have A/C compressors, rear window defoggers, or electric seats. Our bikes are rated @90 hp. That's measured at the crankshaft. The average loss to the rear wheel runs about 15% as shown on the dyno. That would be around 75hp. Vic's post on changing over to amsoil oil, by his own admission, showed a dismal 67 hp, even after the oil change. Even taking into consideration that it wasn't a fresh motor, you could conservatively guesstimate 5-8 hp loss. If you want to go real fast, you'll sacrifice economy. If you want an external alternator, you'll have to give up a small amount of hp. Nothing is free.
I have no way of knowing how much resistance is created by spinning the stock rotor through a bad stator. Probably not too much.
Yes. Your stator is going to fail. An external alternator will fail eventually too. I'm not convinced that the external will have a lot more "dependability". But it is definately easier to change.

How many of us have alternators quit in our cars, lots perhaps, I for one, but yes after removing the engine twice already and not wanting to do it a third time, it easier to change.

I would venture to say that wether the electricity is made on the outside or the inside of the engine that it will still take the same amount of horsepower to produce it. Typically, the worst repair you'll find with the external alternator is a burnt rotor or stator but realistically what you will find after 60 -100 thousand miles is worn brushes that can be replaced very easily and inexpensively but considering the low purchase cost of the external alternator you could replace it every 100 thousand miles yourself and be many dollars ahead of replacing the stock stator just once.