AGM Battery

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vmf1200

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The battery on my 88 is weak so I ordered an AGM battery (Absorbed Glass Mat). Has anybody tried one on their bike? I was searching for an alternative to the typical wet acid type batteries that I find myself buying every 3 years or so. The technology has been around since the 80's mostly in military vehicles. The sulfuric acid is absorbed by a very fine fiberglass mat, making the battery spill-proof and its a sealed maintenance free. AGM has very low internal resistance, is capable to deliver high currents on demand and offers a relatively long service life. So I will update when I get it and put it in.
 
I've had great luck with an Odyssey PC680, first one lasted 8 years. I did have one issue caused by me not realizing I had a draw from a USB charger for my phone that was drawing power which flatted my battery is storage. The great thing about AGM is that you can recover a flat battery which I used twice over the 8 years I had it, see link here for the how to: http://www.odysseybattery.com/documents/ProceduretorecoverdeeplydischargedODYSSEY.pdf
I tried another brand's agm battery and I had issues after one year and it would not recover. I now have another Odyssey PC680 in Redbone looking for another good long life from it.
 
Well that's good to know, I just found out about these type batteries recently. I ordered a BikeMaster one not an Odyssey, but it was the only one that came up that was compatible with my bike listed through Amazon. Here is the link to the one that I ordered.

https://www.amazon.com/gp/product/B005G541B8/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
I hope that it will last longer than the 3 years my current one did.
Thanks for the replies.
 
So I got the new AGM battery and put it in, the bike started great, then I tested the voltage output while the bike was running and I am only get 12 volts even while revving the bike. So my problem now looks to be either the stator not charging or the R/R is no good,,,,,,correct?? So i'm going to test the stator resistance and the manual says there's no way to test the R/R, so process of elimination i'm thinking?? Either one is an expensive part so any advice or aftermarket substitute, upgrade would be greatly appreciated. :ummm:
 
If you go with a MOSFET regulator, be sure you're not getting a knock off copy. eBay is full of them. Also consider a Series type unit. Lots of info here about this upgrade. If you need a stator, RM Stator sells a high output one. I have posted a discount code here for 20% off. Works out to about $75.00, free ship too.
 
Oh ok, great thanks for the info......I could only find a 5 prong plug not a 3 prong plug like my manual says so I measured resistance from various connectors and was getting around 125-126 ohms equally from all wires. So that is not good,,,,correct??
 
O.E.M. It's a three-prong plug, with white wires. Near the left side behind the battery. Take the left side cover off to locate it. Sometimes the plug gets eliminated and the wires get soldered or connected in some form. An A/C voltage output test is best. Tested on each lead to ground. At 2k rpm I'd expect at least 30 volts AC on each leg. Early Gen 1 R/R 's weren't very good. One from a newer Gen 1 or see Bill's post for an even better upgrade. If the R/R is the problem.
 
Ok I found the wires, there was no plug so somebody replaced the stator before. I measured the 3 wires in combination and I was getting 1.24 - 1.27ohms consistently so that means the stator is no good according to the manual they should be 0.38 - 0.45ohms range. So every bike i ever owned I've had to change the stator and on my 86 Kawasaki Vulcan I had to slide the whole motor over to take the cover off because it hits the frame. So I am not a rookie when it comes to replacing the stator but which ones are good? I know about Rick's Motorsports as they are near my house in New Hampshire and they make good stators but he wants $147 for one, but doesn't have one in stock or I would drive there to get it. My only choice is online and I found RMSTATOR.com which seems like a reputable company in Canada and they want $99.00 so I might go that route. I am going to open a new thread for this since my battery problem went to a stator problem.
 
I took a stator off a Venture engine and it worked very well. Sean in another post mentioned having used for sale. With the Mossfort R/R I'm getting 14 volts off idle with the fan running. I swear my engine runs stronger with a better charging system. Such a beast.
 
RM Stator. I had recently posted a 20% discount code. Use it, and the stator comes in at about $75.00... Cool thing about this stator is the output wires were long enough to get up under the seat, where my Series regulator lives. Direct connection to the regulator plug makes one less connection to worry about. Removing the coils for the COPS conversion allowed me to attach the regulator where the coils were. Also, a Series regulator doesn't get hot, and happily lives under the seat. I liked the performance of the Series unit so much, I modified the Roadstar to a Series unit, also living under the seat.
 
Hi Bill - yes I just read all the info on the R/R upgrade and all the charging problems these Gen1 have so i'm ready to do the upgrade. I also got a reply from Sean, and he seems to think my problem is the R/R anyways and not the stator, man I hope so..... I will keep that RMStator code handy as I am ready to order that if needed, but I will probably change the R/R first since that looks like the original one on the bike and the stator has been changed at sometime.
 
Just for the sake of being thorough, (if you have not done so already), The ground to your R/R is connected through the frame. Some guys on this forum suggested to check for corrosion, since it builds up on that spot.

While inspecting mine, because of a low read-out while charging, sure enough, I found a crap load of corrosion on the peg and hole that the R/R is connected to.

I took a Dremel tool, with a wire brush and cleaned off everything.
I put some dielectric grease and remounted. I did not have to replace my R/R or do any upgrades. That's been 5 years now, and still running strong.
Also, I replace my battery to a Shorai Lithium. Starts up fast and strong,, even faster than a new stock lead-acid battery.

Good luck with that..
 
Just for the sake of being thorough, (if you have not done so already), The ground to your R/R is connected through the frame. Some guys on this forum suggested to check for corrosion, since it builds up on that spot.

While inspecting mine, because of a low read-out while charging, sure enough, I found a crap load of corrosion on the peg and hole that the R/R is connected to.

I took a Dremel tool, with a wire brush and cleaned off everything.
I put some dielectric grease and remounted. I did not have to replace my R/R or do any upgrades. That's been 5 years now, and still running strong.
Also, I replace my battery to a Shorai Lithium. Starts up fast and strong,, even faster than a new stock lead-acid battery.

Good luck with that..

I've never been disappointed with the Shorai battery. $144.00 on sale at Amazon 2-3 years ago. It's very light and compact but has better cranking power than OEM.
I swear my bike runs better with this battery and a good charging system.
 
Ok thank you for that info, I will look at the ground wire. The AGM battery that I got is really good also, I noticed a big difference in starting right away.
 
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