I have a good electrical system but, since it's a '95, I am patiently waiting for a good deal on a '96+ alternator so I can upgrade. The question is, if I find 'good' used one, how can I test it to make sure it's good before putting it on the bike?
Alternator testing - off bike
- Thread starter jaster
- Start date
Blrfl
Natural Rider Enhancement
Call your local alternator and starter shop and see if they'll test it for you.
--Mark
--Mark
John OoSTerhuis
Life Is Good!
Jason Spivy asked:
BTW, I'd never pay more than 50% of new Honda part price for a salvage 40amper... Service Honda was listing them for ~$345 recently. Oh yeah, and save yourself the hassle of having to disassemble your old 28amper's alt shaft assy for the parts to transfer to a new 40amper alt shaft - get the seller to send his. What's he gonna do with it anyway...? Who'd be stupid enough to buy that separately, anyway? And you might as well ask for the wiring harness and fuseblock too. If pushed, I'd probably offer to pay ? price for those though.
I assume you've been to my friend Mike Martin's all-things-ST1100-alt-upgrade webpages:
http://home.insightbb.com/~mmartin36/Alt.htm
And there you'll find the PN of the extra O-ring you'll need when upgrading using a salvage 40amper instead of new stock.
When you get ready to do your upgrade, I've got a tool kit I loan out to STOCers that you'll need to do the job:
http://www.stocrallies.com/st-riders/index.php?topic=545.0
Regards, John
Hi Jason. Your odds are very great that any salvage 40amper will work just fine, regardless of the source; and age/mileage at the time it was pulled off a wreck. Would take a hellofa crash to damage the alt. Any reputable salvage place will test the alt before offering it for sale. Ask them. If you're considering one from a private party, see if they'll get it tested for you before the sale... or get them to agree to half now, the other half after you have it tested. Personally, I wouldn't worry about it if the seller is parting out his own ST1100, especially if he's a STOCer/ST-Owner/ST-Rider/MY-MCer.
BTW, I'd never pay more than 50% of new Honda part price for a salvage 40amper... Service Honda was listing them for ~$345 recently. Oh yeah, and save yourself the hassle of having to disassemble your old 28amper's alt shaft assy for the parts to transfer to a new 40amper alt shaft - get the seller to send his. What's he gonna do with it anyway...? Who'd be stupid enough to buy that separately, anyway? And you might as well ask for the wiring harness and fuseblock too. If pushed, I'd probably offer to pay ? price for those though.
I assume you've been to my friend Mike Martin's all-things-ST1100-alt-upgrade webpages:
http://home.insightbb.com/~mmartin36/Alt.htm
And there you'll find the PN of the extra O-ring you'll need when upgrading using a salvage 40amper instead of new stock.
When you get ready to do your upgrade, I've got a tool kit I loan out to STOCers that you'll need to do the job:
http://www.stocrallies.com/st-riders/index.php?topic=545.0
Regards, John
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OP
OP
My concern is not buying a dead alternator off a wrecked bike. It's more of buying a weak alternator that was mostly working on the bike but will die on me in the next year. DOA is easy to check but weak is more difficult to verify. I'll have to look for an alternator place locally who could test one for me.
50% for salvage is my max so we're in agreement there. As far as the shaft, wouldn't that be part of the alternator? Or am I thinking of something different here? My thinking is an alternator is a complete unit and that's what I'm looking to buy. I have a friend in TX who has access to some good salvage yards and he's going to send me their phone numbers tonight. Lucky for him, they have the bikes indoor and the buyer gets to remove the parts. I'm sure I'll end up funding his parts for the trouble of removing mine from the bike.
I've looked at Mike's site a few times. There's some great info there that should get me through the process when the day comes (hopefully I can get someone to help me out for the cost of beer, food, or some other coveted item ).
I'm aware of the kit from STOC but I don't visit there much. I don't have time for this board and STOC so I'm here mostly. No real reason for that choice other than I found this site first.
50% for salvage is my max so we're in agreement there. As far as the shaft, wouldn't that be part of the alternator? Or am I thinking of something different here? My thinking is an alternator is a complete unit and that's what I'm looking to buy. I have a friend in TX who has access to some good salvage yards and he's going to send me their phone numbers tonight. Lucky for him, they have the bikes indoor and the buyer gets to remove the parts. I'm sure I'll end up funding his parts for the trouble of removing mine from the bike.
I've looked at Mike's site a few times. There's some great info there that should get me through the process when the day comes (hopefully I can get someone to help me out for the cost of beer, food, or some other coveted item
).I'm aware of the kit from STOC but I don't visit there much. I don't have time for this board and STOC so I'm here mostly. No real reason for that choice other than I found this site first.
John OoSTerhuis
Life Is Good!
Jason Spivy wrote (snips):
However, both type electrical charging systems have a separate part that plugs into the engine case: the Alternator Shaft. They differ slightly but both have some common parts, including the split gears that engage the flywheel splines and are spun by it to make AC current. Check your Honda Service Manual for the removal and disassembly schematic pages for your 95 28amper's Alternator Shaft. The 28amper has a Stator with which you are probably familiar and can see that it fits over/onto the the 28amper's Alternator Shaft assembly's base. The 40amper's Alternator Shaft assembly base is different, it has a female splined shaft which the 40amp Alternator's male input shaft fits into. Here's a picture showing the old (top) and new (bottom) parts, using new parts for the upgrade:
By part number, the Alternator is only the big unit at the lower right. Order one (31100-MAJ-G41 ALTERNATOR ASSY.) and that's all you'll get.
And here's picture of what a newly assembled Alternator Shaft assembly looks like after the parts from the old 28amper's Alternator Shaft assembly have been transferred to the new shaft, bearing, and base upgrade parts:
This is the Alternator Shaft assembly I was referring to when I said that it should be pulled and sent with a salvage 40amp Alternator. BTW, click on either of the inline pictures and then the 'next' thumbnails at my Webshots album for a better idea of what's involved in the upgrade procedure.
Push come to shove, I guess you could pay your salvage source ? price of new for the alt shaft, bearing, and base parts... as long as he/she sends you the whole Alternator Shaft assembly as is. Think about it... if he disassembles the alt shaft assembly for the Shaft (w/Bearing) and Alternator Base parts that you need for your upgrade, who the hell is gonna need/buy the leftover split gears, shaft flywheel, washers, nut and other assorted parts from it...? Any upgrader will have those parts from their old 28amper's alt shaft assy anyway!
I can send you some 8-bit grayscale jpgs of the 40amp alternator service manual pages if you don't have access to them otherwise and would like to see them.
Regards, John
You wouldn't be the first to be wondering about that, Jason. But spend a little more time on Mike's site. The 28amper and the 40amper are different animals. The 28amper is an older type motorcycle alternator. It's oil cooled, has a separate voltage regulator/rectifier, and is rpm dependent (max output at 5K). The newer automotive type 40amper is air-cooled, has a built-in VRR, and it makes >14.0 volts right off idle.
However, both type electrical charging systems have a separate part that plugs into the engine case: the Alternator Shaft. They differ slightly but both have some common parts, including the split gears that engage the flywheel splines and are spun by it to make AC current. Check your Honda Service Manual for the removal and disassembly schematic pages for your 95 28amper's Alternator Shaft. The 28amper has a Stator with which you are probably familiar and can see that it fits over/onto the the 28amper's Alternator Shaft assembly's base. The 40amper's Alternator Shaft assembly base is different, it has a female splined shaft which the 40amp Alternator's male input shaft fits into. Here's a picture showing the old (top) and new (bottom) parts, using new parts for the upgrade:
By part number, the Alternator is only the big unit at the lower right. Order one (31100-MAJ-G41 ALTERNATOR ASSY.) and that's all you'll get.
And here's picture of what a newly assembled Alternator Shaft assembly looks like after the parts from the old 28amper's Alternator Shaft assembly have been transferred to the new shaft, bearing, and base upgrade parts:
This is the Alternator Shaft assembly I was referring to when I said that it should be pulled and sent with a salvage 40amp Alternator. BTW, click on either of the inline pictures and then the 'next' thumbnails at my Webshots album for a better idea of what's involved in the upgrade procedure.
Push come to shove, I guess you could pay your salvage source ? price of new for the alt shaft, bearing, and base parts... as long as he/she sends you the whole Alternator Shaft assembly as is. Think about it... if he disassembles the alt shaft assembly for the Shaft (w/Bearing) and Alternator Base parts that you need for your upgrade, who the hell is gonna need/buy the leftover split gears, shaft flywheel, washers, nut and other assorted parts from it...? Any upgrader will have those parts from their old 28amper's alt shaft assy anyway!
I can send you some 8-bit grayscale jpgs of the 40amp alternator service manual pages if you don't have access to them otherwise and would like to see them.
Frankly, there's far more ST1100 owners/experienced-'wrenches', and upgraders in particular (I know of 50+), over on ST-Riders, if you're really serious about looking for help... thinking about an altSTOC of some sort... JMHO, of course.I've looked at Mike's site a few times. There's some great info there that should get me through the process when the day comes (hopefully I can get someone to help me out for the cost of beer, food, or some other coveted item
Sure, I understand. Just follow my tool loan instructions at the link when you're ready to do the deed.
Regards, John
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OP
OP
Thanks for the additional info. I see what you're referring to as the shaft and why it's not included with the alternator. The one I have located now is just the alternator and no base plate or shaft. I might be able to get those as well but I haven't asked.
Lucky for me, my friend in TX is a much better mechanic than I. If I can find a better deal on an alternator there, I'll forward him these pictures so he knows what to grab for me. From what he's told me in the past, I doubt the extra parts will be a cost issue.
The 40A manual would be great. I'll send you a private message with my personal e-mail so you can send it over.
I'm sure I'll get a little active at ST-Riders once I get serious about the upgrade (read that to mean once I actually have half the parts in hand). An altSTOC would be excellent if it were somewhere/sometime I could attend. I'd even get brave and throw mine in as a donor bike so others can see how it's done.
Lucky for me, my friend in TX is a much better mechanic than I. If I can find a better deal on an alternator there, I'll forward him these pictures so he knows what to grab for me. From what he's told me in the past, I doubt the extra parts will be a cost issue.
The 40A manual would be great. I'll send you a private message with my personal e-mail so you can send it over.
I'm sure I'll get a little active at ST-Riders once I get serious about the upgrade (read that to mean once I actually have half the parts in hand). An altSTOC would be excellent if it were somewhere/sometime I could attend. I'd even get brave and throw mine in as a donor bike so others can see how it's done.
wjbertrand
Ventura Highway
The 40A alternator is so similar to a cage alternator, I wonder if you couldn't have it tested at your neighborhood auto parts store? They can do a nice load test, diode and reg/rec test as well. Most of the stores around here will do it for free.
John OoSTerhuis
Life Is Good!
Jason Spivy wrote (snips):
http://home.insightbb.com/~mmartin36/JohnO_list.htm
As I mentioned before, the only new part you'll need if going the salvage route is the big O-ring.
Regards, John
You're welcome, Jason. You need parts other than just the alt and alt shaft. Once again I refer you back to Mike's site for a list of all the parts, Honda part number/noun-nomenclature and other parts, plus the tools that you'll need to do the upgrade:
http://home.insightbb.com/~mmartin36/JohnO_list.htm
As I mentioned before, the only new part you'll need if going the salvage route is the big O-ring.
Have him grab the other parts too, like the fuse block and its bolts, the wire harness... etc.
You should have all the Honda Service Manual pages now. I zipped them and attached to an e-mail to your address.
Heh, heh... I meant YOU could host an AltSTOC and invite fellow STriders, especially those that have done an upgrade. BTW, I could possibly be persuaded to hand-deliver my upgrade tool kit and help... send me a round trip plane ticket.
Regards, John
Jason: When you get around to doing the upgrade, consider doing what I just did on my 92 which was upgraded a few years back. The changes made a huge difference on system voltage. Go here to read about my experience and what I did:
http://www.stocrallies.com/st-riders/index.php?topic=726.0
http://www.stocrallies.com/st-riders/index.php?topic=726.0