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Discussion Starter #1
hi all

I fried my reg/rec and bought a new one. changed the location as i put a tyga kit on and it wouldnt fit in the original position. i bolted it to the exhaust bracket. i changed the wiring and connectors as well. i put a volt meter on it to test the battery yesterday and got some wierd readings
bike off/closed ignition 12.36V
open ignotion with low beams on and in neutral 11.97V
idle at 1600rpm 12.58
3000rpm 14.20v
5000rpm 13.80V
8000rpm 13.50V

does this sound normal to anyone?

i checked the wiring again today on the reg/rec and it all seemed fine. i turned the bike on and took the seat off to test the battery again. while giving it a bit of a rev on about 3000rpm i saw smoke coming from the connector that sits in the battery cradle. it has 3 yellow wires simular to the 3 wires that go into the reg/rec.

not sure if they are the same wires or not??

the connector and wires were burned to a crisp.

would the loss of power (voltage on battery) on higher revvs be related to this issue? or is it something different all together?

could i have possibly connected one of the yellow wires on the reg/rec in the wrong slot on the connector? would that fry the other connector next to the battery? i attached pics

also bike seems to riding fine

[attachment=72]
[attachment=73]
[attachment=72]
[attachment=73]
 

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Tony?

Justin.
 

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It looks as if that connector has drawn a lot of current and melted, this can cause the connectors to touch each other as the shell has warped.

Tony is the expert on Regs on these bike and I'm not sure if all of those three wires come from the Stator to control the voltage are all related as one.

Getting a higher voltage with 14v is normal as the RPM increases. The CBR alternator is an amazing unit considering it has a charging range from 2000 to 20000 rpm. I'm sure under a certain amount of load at idle it won't be charging at all though.
 

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Discussion Starter #4
ASTAR said:
It looks as if that connector has drawn a lot of current and melted, this can cause the connectors to touch each other as the shell has warped.

Tony is the expert on Regs on these bike and I'm not sure if all of those three wires come from the Stator to control the voltage are all related as one.

Getting a higher voltage with 14v is normal as the RPM increases. The CBR alternator is an amazing unit considering it has a charging range from 2000 to 20000 rpm. I'm sure under a certain amount of load at idle it won't be charging at all though.
yeh hopefully Tony can shed some light on this. having a look at the wiring diagram now to see if the yellow wires coming out of the reg/rec goes to this connector that is now fried then into the alternator as the colours on fried connector are yellow as well as the reg/rec wires.

i know the alternator doesnt charge the battery on idle but the thing is that it goes to 14V at 3000rpm but after that it begins to drop lower than 14V on higher revvs. shouldnt it go higher the more you revv?
 

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Wayne: Semantics, but I believe the alternator provides power at all RPM's and loads, whether it's 'charging' or not is determined by whether the power from the alternator is greater than the current power consumption of the bike (which varies based on what electrical systems are running on the bike at the time).

I know I'm not telling you anything you don't know, just clarifying the point for the new kids :blush:

Justin.
 

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sir.b said:
Wayne: Semantics, but I believe the alternator provides power at all RPM's and loads, whether it's 'charging' or not is determined by whether the power from the alternator is greater than the current power consumption of the bike (which varies based on what electrical systems are running on the bike at the time).

I know I'm not telling you anything you don't know, just clarifying the point for the new kids :blush:

Justin.
Yes true! But it's hardly efficient at low RPM. It's the same reason why Tony programmed his headlight kits to stay dim at Idle. Or try putting high watt lights in a CBR and see how far the idle drops at low RPM. The alternator just isn't setup in terms of output ratio at low RPM. But I guess the majority of my examples are based on load at idle - I’m sure it just manages to keep the battery charged without excessive load.

A lot of people don't understand that the alternator just can't have the same output at 2000 rpm as it would at 6000 rpm, especially with a 20,000 rpm range. But Honda would've set the alternator to perform at peak at cruising and light load applications.
 

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I've got a faint recollection of Tony saying that they actually have a power deficit at idle with the high beams on, but a slight surplus with just the low beams running.

Justin.
 

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Discussion Starter #8
sir.b said:
Wayne: Semantics, but I believe the alternator provides power at all RPM's and loads, whether it's 'charging' or not is determined by whether the power from the alternator is greater than the current power consumption of the bike (which varies based on what electrical systems are running on the bike at the time).

I know I'm not telling you anything you don't know, just clarifying the point for the new kids :blush:

Justin.
you learn something new everyday. i was under the impression that it didnt produce any power at idle. just to confirm, it does produce current but its lower than what the bike needs so the rest of the power comes from the battery?
 

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True, again I guess it's load based. But that can result in battery condition (resistance) other electrical loads(heated grips, neon lights and wrong globes) and Reg performance.

Most of the time if your Reg has shit its self - but still works - it will over charge the system and make the battery cook. Resulting in a bad egg smell and a warm bum. This is why Tony installed a over charging warning in the Shift i of 16v - which is just under the maximum charging capacity of the CBR Stator.

Im sure if he replaced the plug shell, checked his earth and made sure he used head conducting paste on the Reg - it will all work fine.

I used the CBR1000 Reg on my CBR 250. Because it had cooling fins for extra cooling and was in my theory newer components running bigger diodes. Tony has some good units for sale now that he has tested to work very well. And they are a quarter the price.:hail:
 

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robbie said:
you learn something new everyday. i was under the impression that it didnt produce any power at idle. just to confirm, it does produce current but its lower than what the bike needs so the rest of the power comes from the battery?
Yeah that's exactly right mate.

Here's the power output of a couple of alternators:


You can see that they start making power as soon as they start spinning, and that the power increases as the RPM's go up.

Justin.
 

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Discussion Starter #11
sir.b said:
robbie said:
you learn something new everyday. i was under the impression that it didnt produce any power at idle. just to confirm, it does produce current but its lower than what the bike needs so the rest of the power comes from the battery?
Yeah that's exactly right mate.

Here's the power output of a couple of alternators:


You can see that they start making power as soon as they start spinning, and that the power increases as the RPM's go up.

Justin.
but on my bike im getting 14.2V on the battery at 3000rpm but instead of it picking up, its dropping as the revs go up. i thought it was meant to get higher the more you rev, but it shouldnt climb over 15V or it would mean you have a big problem as well.

i understand that the power output doesnt depend on revs and all alternators tend to give the most charge at cruising speed, but surely on a MC22 3000rpm cant be the cruising speed...

i dont know why this is happening and why connectors are getting fried and melting. my theory is that the burnt connector pictured couldnt handle the load and its not giving the full voltage at higher rpm's? im a noob so im pretty sure i got it wrong though.... :s

first step is to find out where the wires coming into the connector are coming from and where they go and what caused it to burn and melt.... any ideas?[hr]
from what i can see on this wiring diagram the connector that melted comes from the reg/rec and runs the yellow wires from the reg/rec towards the battery. the connector sits in the battery bracket then the other end of the connector goes to the alternator. im not too sure if this is correct though..... i dont know what caused it to melt like that though????? i dont want to just changed the connector and wires if its just going to happen again. i would rather find out why it happened and fix it.

im afraid that i might have put the wrong yellow wire in the wrong slot on the reg/rec connector wires that i replaced.

any anyone confirm if im correct and if im wrong,any suggestions?
 

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robbie said:
but on my bike im getting 14.2V on the battery at 3000rpm but instead of it picking up, its dropping as the revs go up.
What you see in the graph isn't voltage output, it's amps. The reg/rec then regulates the voltage, so the variance you're seeing is probably (Tony will confirm and diagnose when he sees this thread) within the normal range of a reg/rec output. I don't think [email protected] is anything to be concerned about, it's not spiking/dropping all over the place, but I'm interested in seeing Tony's response.

Justin.
 

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Discussion Starter #13
sir.b said:
robbie said:
but on my bike im getting 14.2V on the battery at 3000rpm but instead of it picking up, its dropping as the revs go up.
What you see in the graph isn't voltage output, it's amps. The reg/rec then regulates the voltage, so the variance you're seeing is probably (Tony will confirm and diagnose when he sees this thread) within the normal range of a reg/rec output. I don't think [email protected] is anything to be concerned about, it's not spiking/dropping all over the place, but I'm interested in seeing Tony's response.

Justin.
Ohh ok no thank you. I've learnt more on this forum in a week than I ever thought I could. Hopefully Tony can help.

This is the best forum I've ever been on. It's very social and productive and very busy so you don't have to wait long for an answer. It's very active and everyone helps each other out. That's awsome!!
 

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robbie said:
Ohh ok no thank you. I've learnt more on this forum in a week than I ever thought I could. Hopefully Tony can help.
This is the best forum I've ever been on. It's very social and productive and very busy so you don't have to wait long for an answer. It's very active and everyone helps each other out. That's awsome!!
Awesome to hear :headbang: It's good to get positive feedback from someone new rather than the normal "you guys are fucked, this place has the worst reputation on the whole internet" that we're used to :blush:

There are a few guys on here that know these bikes like the back of their hand, once they've diagnosed problems a handful of times the rest of us plebs tend to catch on and jump at the chance to use what we've picked up :) Then a tricky electrical one comes along and everyone sits back and waits for Tony :blush:

Justin.
 

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That connector is the one that connects the alternator wires through to the regulator rectifier plug.

The reason why they've melted is because of heat and/or poor contact. If two of those wires were shorting somewhere or there was a very high load current, then a lot of current would have gone through those connector terminals, which would cause obvious problems. However I expect this is from poor contacts. If the terminals aren't gripping each other with sufficient force (loose), the conductivity is low. A lot of current is going through a poor contact, and that contact will get very hot. In turn, it will oxidise and get even worse. Alternatively, it could have started with grime/dirt causing poor conductivity and the downward spiral started. A lot of modern bikes have a grease in the connectors to prevent dirt/grime from degrading the contacts. Some people wash out this grease with WD40 to expose the connector hahaaa....

I'd personally replace the yellow wires and the connector. The wires have gotten too hot and probably brittle and not provide good contact for new terminals. Otherwise, make sure to inspect the yellow wires to ensure there is not damage or melted insulation. New connector! Doesn't have to be the same one, just an automotive high current 3 pin connector.

The alternators efficiency is not constant. If fact it will peak and then go down at the high end of RPMs. The problem that Honda had, was getting an alternator that is going to pump out power across a very large RPM range. I'm not sure they target the peak at cruising speed. Rather try to optimise what they can get for the usuable RPM range. Of importance... the ignition takes power. The faster the RPM is, the more sparks that need to be generated.... more power needed. Headlights however suck a fair bit of power and are quite significant.

The CBR250's alternator does generate power at idle. Just not enough to run 60W headlights or to charge the battery with the headlights on. A battery needs a certain level above it's normal voltage before it starts absorbing power (of any significance). It's a chemistry thing. Idling at 12.5V won't do it. Seeing the voltage drop off with higher RPM is not good, but also not unexpected... ignition power consumption increases. My 675's alternator drops off a bit, and that a recent model.

But all this gets a lot more complicated when you consider the combination of the alternator and the reg/rec. The alternator is generating an AC signal, where the voltage amplitude varies with engine RPM and load. The reg/rec will clip the voltage that's too high and convert it to heat (energy lost). However if the load is high enough, the voltage might not be as high, but the current is high and the losses in the reg/rec increase proportionally (more heat). Don't think too hard about that, as it'll mess with your head.

It's not precisely straight forward to compare one bike with another, as the battery itself will present a different load on the alternator system. If the battery is low on charge or in bad health, it makes it much more difficult to determine if there is a performance problem with the reg/rec and/or alternator.

In this case... I'd recommend to fix the damaged wiring, charge the battery and re-test. Also... make sure the reg/rec has good contact with a lot of metal... so it can sink and dissipate the power.
 

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robbie said:
This is the best forum I've ever been on. It's very social and productive and very busy so you don't have to wait long for an answer. It's very active and everyone helps each other out. That's awsome!!
Surely you must be on drugs? :) This place has the worst reputation on the internet, bar none. :p

The yellow wires from the alternator are effectively all the same. The alternator has three seperate coils in it, each of which have a current generated in them by the magnet spinning around on the end of the crank. Because the coils are spaced 120° apart, the three wires together make up a 3-phase AC power supply, one phase per wire.

The rectifier is basically a diode bridge that converts this 3-phase AC into DC. Because current can only travel through a diode bridge one way, the order in which the three yellow wires are connected into the rectifier does not matter. That's why they're all the same colour.
 

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sir.b said:
There are a few guys on here that know these bikes like the back of their hand, once they've diagnosed problems a handful of times the rest of us plebs tend to catch on and jump at the chance to use what we've picked up :) Then a tricky electrical one comes along and everyone sits back and waits for Tony :blush:

Justin.
Hahaa... it's rather good, as some times I'II find a thread where a few people have already chimed in with answers. Sometimes it's even surprising the details remembered :cool:

So I guess I'II get replaced and retire sometime soon :popcorn:
 

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Discussion Starter #18
And this is why your the man Tony! I'm going to change the connector tomorrow. I was worries that I might have connected one of the yellow wires into the wrong slot on the reg/rec. There's three yellow wires and thought maybe I got one crossed and that's what shorted the connector on the other end. Do you think that could have played a role? The battery didn't die. The bike still starts and it doesn't seem to have lost much power. I've mounted the reg/rec onto the exhaust bracket so the entire thing is on metal and I've put thermal past on it too.
 

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Eclipze said:
So I guess I'II get replaced and retire sometime soon :popcorn:
Just read your reply, don't plan on getting out of here before you're 65.

Justin.
 

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Very good ;-)

No problem with getting the yellow wires around in different spots. Stavros has that one answered well. It makes no difference and wouldn't have caused the problem.

A big cause of melted plugs on the reg/rec's is that the terminals have loosened off. Happened with my VFR400. Terminals are junk after that happens.
 
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