Diagnose this?

[CookMySock]

Sounds like you are on the right track so far ;

Theres definitely a low-voltage problem of some sort. When you hit the starter do the lights dim right down? No click-click-click, just dim?

Battery voltage is clearly low - charge overnight and see if the battery voltage returns to 13V ish, if so the battery is probably fine. Bike should start perfectly well now. If battery stays under 12V and starter is sluggish then battery is rooted.

Engine running at @4000rpm battery voltage should rise with the revs to 13.5 - 14V ish.

Check the AC stator output phase-to-phase - should be 40-70V between any combination of the three yellow wires.

Stop engine(!) and test ohms any stator wire to bike frame - should be very high resistance or infinite.

Test regulator with tester using this diagram ;


If it passes all those tests, then its all in your head.

Steve

[tigertim20]

They are oxford grips, and I didnt try them this time.

When trying to start, there is no click click click, just a slight dim, barely noticeable. Thing is, when I push started it, got it running, went for a ride again, twice I was riding along, and it just sort of lost power, and kinda went bbuuuuurrrrrrrrrrrghh to a stop, like all power was suddenly lost, So I am leaning further towards reg/rec being fucked, cos if reg/rec is fucked, battery will not charge, also, if it IS the reg/rec, that would explain the bike stopping, as reg/rec would be powering he bike while its running, when it fails, bike dies, am I on the right line here? If so, we are looking at either a loose wire, or reg/rec.

Wil charge battery up today and test the current on it, just to (hopefully) eliminate that as a possibility

[tigertim20]

oh, and no alarm

[lankyman]

Yea Honda Reg/Rec's are shithouse mate. Fryed 2 on my NC30 so far. It's got a Ducati one now. Also had my earthing strip terminal (to the negative side of the battery) break off right up inside the terminal where I couldn't see. Looked fine and seemed fine when I wriggled it, it wasn't until I actually pulled the battery out and the terminal fell down inside my fairing did I know that is was broken off.

[NDORFN]

Have you checked the kill switch on the stand? (if it has one). Isolate that and see if it makes a difference.

[The Pastor]

sounds 90% like a crap batter or r/r

could also be a side stand swtich, they are prone to breaking.

if your bike requires the clutch to be in to start, it could also be that switch.

i'd start with the battery, they are cheap enough to replace but if its the r/r (can be up to 200 bucks!) it could damage the new battery!

[MSTRS:Me]

...if it IS the reg/rec, that would explain the bike stopping, as reg/rec would be powering he bike while its running, when it fails, bike dies, am I on the right line here? ...

Sort of, but not quite. The alternator is (should be) producing voltage when the engine is running. This voltage is directed to the battery via the R/R which 'adjusts' the voltage to about 13.5v so the battery does not get an overage.
If the R/R is poked, it will either stop power to the battery or will allow too much through...battery toast. If alternator coil is dodgy then no/not enough power will get to R/R in the first place.
Engine will run as long as the battery can output enough voltage to the firing system.
Your problem suggests one of, or combination, poor alternator, poked R/R, bad connection at the battery or elsewhere. If your battery was too flat, your engine wouldn't go now and stay that way.

[vifferman]

Yea Honda Reg/Rec's are shithouse mate.

Guess what? 'Honda' R/Rs aren't made by Honda - they're made by Shindengen, who also happen to make R/Rs for many other bike manufacturers (including Ducati).
The problem isn't the R/R - it's that Honda choose to fit smaller (cheaper?) units then hide them under bodywork, where they overheat, and also fit wiring and plugs that are of a too small gauge, which also shortens the life of the R/R.
It took until 2001 before Honda fitted decent R/Rs to the VFR; before that they just pretended there wasn't a problem, despite better R/Rs being available from Shindengen from around 1990.

[CookMySock]

When trying to start, there is no click click click, just a slight dim, barely noticeable.

That is odd. If the battery is flat, the lights should dim heavily on starting, (unless they are HIDs where they won't dim at all.) If it clicks, that is usually a loose terminal.

Thing is, when I push started it, got it running, went for a ride again, twice I was riding along, and it just sort of lost power, and kinda went bbuuuuurrrrrrrrrrrghh to a stop, like all power was suddenly lost.

Well I do not have any experience with that fault. I thought the engine would run on its' CDI, regardless of any alternator output, battery connected, or anything in the 12VDC electrical circuit at all.

So I am leaning further towards reg/rec being fucked, cos if reg/rec is fucked, battery will not charge, also, if it IS the reg/rec, that would explain the bike stopping, as reg/rec would be powering he bike while its running, when it fails, bike dies, am I on the right line here? If so, we are looking at either a loose wire, or reg/rec.

Can someone comment on this, specifically. Does the CDI require the 12VDC circuit to function?

I enjoy this diagnosis stuff.

Steve

[Ragingrob]

When my CBR fucked the reg/rec it was completely intermittent, the bike would just lose all power on occasion and the battery would not have enough oomph to start. Then other days it would start absolutely fine.

And yeah it was just the reg being the problem.

DangerousB yeah they need voltage surely. Think of all the race bikes that have the charging systems removed for less weight but they still need a batt to keep the power going.

[been_there]

Had the rectifier shit itself on my triumph after having it only 3 weeks. So definetly not just a Honda thing.
I have managed to find a mod that I will be doing to avoid any future problems.

http://www.triumphrat.net/speed-trip...r-upgrade.html

[mossy1200]

If the battery was not receiving charge your battery would be well below the 11volts before your bike stopped.The voltage regulator should deliver around 13 volts at idle and 14 to 14.5 at 4000rpm.Its not voltage that charges the battery but the current delivered.Big charging system still deliver the same voltage but more current therefore they charge quickly.You need to put clamp on ameter onto output from rectifier onto battery.As the battery reaches full charge the current drawn reduces.
I think you will find that if you have enough battery to run lights with bike off then you have more than enough to run coils.
Check you handle warmers are not shorting to ground.perhaps disconnect them.if your warmers were connected to ignition circuit and they short to ground then its like turning the key off as far as the bikes concerned.Disconnect and ride your bike.

[tigertim20]

When my CBR fucked the reg/rec it was completely intermittent, the bike would just lose all power on occasion and the battery would not have enough oomph to start. Then other days it would start absolutely fine.

And yeah it was just the reg being the problem.

DangerousB yeah they need voltage surely. Think of all the race bikes that have the charging systems removed for less weight but they still need a batt to keep the power going.

That is handy to know! sounds exactly like what I have had happening.
It started fine again this morning. What I have done is charge the battery overnight, The battery is sitting at 13.2 when bike is off, jumps to 14.2 at idle, and up tp 14.8 at 14000rpm.
Now yesterday, I pulled all the plugs out of the reg/rec and contact cleaned both ends with contact cleaner, was quite alot of shit in there, so it MAY have just been the contacts. Now that the battery is charged, and bike is starting, I will ride it for a week, seeing as the readings appear to have returned to normal, If it shits out again, then its either the reg/rec, or one of the associated wires are loose is my thinking.