I'm back again with an update. I still don't see >13V when riding. I installed the MOSFET R/R (wow, very straightforward install! it went very well) and also performed the blue wire mod (wow...even more of a straightforward mod). I finished an hour long ride today and my battery reads 12.54V. That's over 90% charge, not bad!
However...
As soon as I flip the key to on (engine is still off), this voltage drops to 12.12V. Could it be an issue with the Junction Box? Could it be my onboard voltage meter attached to the turn signal wiring causing an issue? (I'm grasping at straws here I feel like, haha).
This issue existed prior to my MOSFET install. Any thoughts as to what's going on here? In a previous post I share the results of my stator test and the stator checks out, so I don't think it's that. Something else perhaps is going on here.
As soon as you flip on the key you’re applying a load to the battery. That’s not entirely odd to see a voltage drop. Especially if you have standard bulbs (non LED), you’ll get your best readings if you can have a voltmeter hooked up while riding.
This is great for my own understanding as well, thank you for that insight. I do have standard filament headlight bulbs and turn signal (front) bulbs. Only the rear turn signals and brake light are LED (combination unit). So this makes sense.
What doesn't make sense is why with the new MOSFET R/R I'm not at appropriate charging voltage (~14 to 14.5V) when I'm riding at speed. My onboard voltage meter (again, connected up to the turn signal wire in the headlight assembly) only yields me ~12.5 or 12.7V at speed. I'll check it again later with my hand held volt meter directly on the battery while revving (maybe the onboard voltage meter isn't calibrated correctly).
My voltmeter is hooked up to my accessory leads as well and it’s not the greatest voltmeter either but it works. Sometimes it’s off a few tenths of a volt when I compare it to my multimeter across the battery.
You could pull out the fuses for the lights/accessories and start it to se if it yields any different numbers a different rev ranges.
My voltmeter is hooked up to my accessory leads as well and it’s not the greatest voltmeter either but it works. Sometimes it’s off a few tenths of a volt when I compare it to my multimeter across the battery.
You could pull out the fuses for the lights/accessories and start it to se if it yields any different numbers a different rev ranges.
12.7v at speed is really low.., especially if the fan is off. Something isn't right. That's practically no charging at all but there must be some output because it's keeping 12.7v with all the lights on.
Tanner had an all new charging system and wasn't making good voltage. The Two Wire mod fixed it.
I hate to bring up another mod, but something is pulling the voltage down.
I don't know if it would help to pull fuses while watching the voltage, engine running. Maybe...
Just trying to figure out how to have the bike running while drawing the least amount of load. Wouldn’t pulling the two 10amp fuses cut most of the lights out of the picture?
If I’m in traffic and the fan kicks on my bike will show 11.x on the meter if I’m sitting for a while. My idle is right around 1000rpm. As soon as I can move and get on the throttle the meter jumps up to 13.x. The highest I’ve seen on it is probably 14.2 on my dash meter which probably translates to 14.5 directly at the battery. This takes into consideration the cheap onboard voltmeter and any loss across the bikes wiring through the accessory leads.
This is EXACTLY what I'm seeing as well. When my fan kicks in sometimes my voltage drops to yellow (I forget what this correlates to...maybe 12 or 12.5V). Then when the fan kicks off I'm back to 14.5V.
If you pull a fuse and voltage rises significantly, that circuit has a problem. A minor rise is expected because lights may shut down, etc.. This test may not prove anything.
The mosfet install bypassed all the old RR wiring, correct? I'm trying to think of where the short can be.
With a good stator and mosfet kit, you should be able to remove the positive wire coming from the mosfet at the battery and read really good voltage on that wire, like 13.5-15v. So try that. I think that should prove if the system works or not.
If it has good voltage there, then we have to look at the battery and electrical system.
Yes, the MOSFET regulator bypassed all the old R/R wiring.
I pulled fuses and found that with the headlight fuse out, I'm back at nominal charging voltage! I finished an hour long ride last night at sunset with a battery that reads 100% charge! So I'm going to ride again today after work to make sure all is the same. And next on to troubleshooting! Is it the Amazon headlight I put in over Christmas break? Is there a short or some issue in the headlight housing? We shall see!
Thank you for the guidance and troubleshooting help. I'll come back to post a summary update of everything, because this bike has never been running better. Also by the way the pickup coil mod is a MIRACULOUS improvement in hot starts! Wow!
Yeah, when I had the headlight in the bulb produced great brightness on "low beam" mode. It didn't flicker or anything. It was even brighter on "high beam" mode. So yes, the high/low beam switched correctly. I'm really hoping it's the Amazon headlight bulb...it'll be an easier fix (basically don't use that bulb anymore!) then I can get an awesome LED headlight. I'll look at it this weekend. But it just feels so good to finish a ride with a battery that reads full charge! Thank you.
I looked at the link but I didn’t find what the wattage of this bulb is. For sanity you can leave in the fuse and meter across the headlight plug. At least that’ll tell you what voltage is being delivered to the bulb
Here is the bulb I have. I’m real satisfied with it, but I did have to remove/bypass the RLU. Before I did it both the bulb and the high beam dash light flickered. Before you change your bulb it's probably best to pinpoint if it’s the problem or not.
I looked at the link but I didn’t find what the wattage of this bulb is. For sanity you can leave in the fuse and meter across the headlight plug. At least that’ll tell you what voltage is being delivered to the bulb
Here is the bulb I have. I’m real satisfied with it, but I did have to remove/bypass the RLU. Before I did it both the bulb and the high beam dash light flickered. Before you change your bulb it's probably best to pinpoint if it’s the problem or not.
Wow that LED headlight looks amazing. Was it a simple plug and play installation as far as the locking ring goes? That what it says on the link but I'm checking with you to confirm. But yeah, you are right that first I'll need to nail down the root cause before going down this route.
There's some interesting 7" LED headlights on eBay, some look like copies of the Daymaker, but I know nothing about about them, except the prices start around $25.
It is a little puzzling, that’s why I suggested testing voltage across the headlight socket to isolate if the bulb is wonky or that circuit has an issue. I know he said he had the fuse out but not just the bulb.
All great stuff, guys. Really! Thank you. I'll get out there and test the charging voltage without the headlight. Then I'll test it on a ride. It's very rainy here this week in Eastern PA so it'll be a few days but I'll post an update promptly.
Yup, I’m down in Philly. This is a “leave the bike parked” type of week. But striper fishing is heating up in NJ and I never met a fish that didn’t like to get wet so it’s a good trade off!
That sounds correct, it was a while ago. I also wanted to mention that I just swapped out the LED bulb not the housing. Wanted to keep the stock look of the bike but just improve the light output. The signals and driving lights are LED as well
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