Flat Battery..SOMETIMES... HELP PLEASE!!

[geoff916]

Help ! My 2000 "bird works fine 99% of the time, BUT. Every so often, maybe every two or three months, I stop, turn engine off, then..it seems like my battery is flat!! after bump start, she is fine again for months !!
I have fitted a new battery (twice) and still this annoying fault appears.

Interestingly, when I indicate, SOMETIMES the rev counter dips to zero for a split second.

Any ideas on what this could be causing this will be most appreciated,

Electrics are standard apart from HID headlamps, LED running lamps off the sidelight circuit and LED brake lights in my Givi box.

Geoff :bang:

 

[Vinterceptor]

In what way does it seem like a flat battery? Does it turn over slowly, just click click click sounds or nothing at all? Do the rest of the electrics work when this happens?
Has the 'loom fix' been done?

Whilst on the Wales run earlier this year we stopped briefly to discuss the route. My bike wouldn't re start after faffing with the kill switch, side stand and ignition switch it started. Was ok for ages then it did it again.

I did the loom fix but it didn't cure that problem, ended up dismantling the rh switch gear and found green crud all over the starter button.

 

[geoff916]

Thanks Vinterceptor, It is as if the battery is flat, so it tries to turn over, but slowly, then after a few seconds, click click click! I haven't done the loom fix to be honest. There is no crud under the switches, I recently fitted Flat bars, so I know all the switches are clean. My son reckons reg / rec ? It has done this a few times over the last 5 years, so I know its nothing I have done with the bar swap.
thanks for your help

 

[ianrobbo1]

Here is likely to be the problem with your bike, and welcome to the site @tu*

http://www.bikersoracle.com/blackbird/forum/showthread.php?t=16438&highlight=loom+fix

 

[andyBeaker]

Here is likely to be the problem with your bike, and welcome to the site @tu*

http://www.bikersoracle.com/blackbird/forum/showthread.php?t=16438&highlight=loom+fix

Plus one on this.

Just do it, the root of all sorts of weird electrical issues on Birds.

To be honest even if it doesn't solve your immediate issue then it will prevent another.

Did you get the 'old' batteries checked when you replaced them? Would have given a clue about the health of the charging circuit.

However, testing the generator and reg/rec is dead easy with a multimeter, see thread at top of Help,section.

There seem to be quite a few instances of ignition barrel wiring problems coming through on Birds as they are now approaching vintage status:-0), could potentially be the source of the problem as well.


Keep posting..... But do the loom fix first, regardless of what condition you think the wires are in

 

[geoff916]

Upon further investigation, I find the "fix" has been done! BUT the three yellow wires from the magneto were connected with "choccy block" connectors, which had melted a bit, no a lot! One of these wasn't even connected at all. and was rather green. The battery is at 12.3 v then rises to 13.6v when rpm is held at 2k, so at least the rec / reg is ok I think. Time to test the output from the magneto methinks.

 

[andyBeaker]

Upon further investigation, I find the "fix" has been done! BUT the three yellow wires from the magneto were connected with "choccy block" connectors, which had melted a bit, no a lot! One of these wasn't even connected at all. and was rather green. The battery is at 12.3 v then rises to 13.6v when rpm is held at 2k, so at least the rec / reg is ok I think. Time to test the output from the magneto methinks.

I have come across the terminal block method before and it caused a fried generator... I would guess the result of a short when the plastic on the block melted.

first test on the generator is to check for earth connectivity with the generator disconnected - 20p says that there will be a circuit, no need to check the outputs as it is terminally screwed.

Remember to order a new gasket when ordering the generator from JAWS.

Apologies if above is sucking eggs for you:-0)

Post up the outcome as this subject is a regular on here. Brunel didn't give enough thought to the charging system when he designed the Bird unfortunately.;-0))

 

[geoff916]

So....put my meter on two of the yellow wires from the Generator. Results as follows

1-2 0.8v
2-3 16.8v
1-3 17.4v
New generator is required methinks

Strange though Battery is showing 12.4v rising to 13.6 @ 2000rpm 14.4 when rpm is 3000, then it does not get any higher even when rpm is 5000. respect for neighbors only let me rev it for a cpl seconds though.

 

[andyBeaker]

Good news you have found a problem@tu*.

Be aware that you will need to solder the connectors onto the new generator when it arrives as they are supplied loose. Other than that it is a very straightforward job. If it is the first time it has been replaced it will probably be a pain scraping off the gasket, if it has been done before then I have always found the gasket to be loose, whole and reusable. Top tip is to fix the gasket in place with a few smears of grease to hold it in place as it is spanner throwing territory otherwise:bang:

Don't panic if a gear wheel and dowel falls out when you take the generator cover off, it is easy enough to put back in place:-0)

Also check the reg/rec and battery when the new generator is installed as it is very common for systemic damage to have happened through the charging system when one component goes phut.

Personally I believe that all three components should usually be replaced for this reason, but hopefully as you have a very specific cause in your case you have got away with it.

 

[Judge Dredd]

Also check the reg/rec and battery when the new generator is installed as it is very common for systemic damage to have happened through the charging system when one component goes phut.

Personally I believe that all three components should usually be replaced for this reason, but hopefully as you have a very specific cause in your case you have got away with it.

+1 for that. Found that out to my cost. Should have changed the lot the first time.

 

[andyBeaker]

+1 for that. Found that out to my cost. Should have changed the lot the first time.

Personally I would but I do accept that there are times when this means a perfectly good component is replaced.

Depends on risk appetite and possible impact of being without a bike. I relied on mine for work so erred on the side of caution. The thought of using public transport made it an easy choice sh1tehppns

 

[geoff916]

I only use "her" for fun, Will replace the genny first, then see what, if anything else has fried! Soldering the wires would be my prefered route anyway. I dont like connectors.
Keep you posted. Thanks guys

 

[andyBeaker]

A further thought on this; in my opinion it is well worth fitting either a digital voltmeter or a LED charging indicator light - or both. Either will give you an instant indication of the charging circuit going phut (it has been known on Birds8rfl@), simple to fit and cheap,as chips on eBay. No need to ponce about with drilling holes to accommodate, plenty room between the top of the instrument binnacle and screen - a bit of Velcro is all that is needed.

Personally I would fit an LED indicator as a minimum as they are very visible, backed up by a digital voltmeter that gives a detailed picture of what is going on.

Again apologies if sucking eggs.

http://www.ebay.co.uk/itm/DC-0-30V-...hash=item51d26bc0c6:m:mEINvMN0HxPlP1Uan_zLOoQ


http://www.ebay.co.uk/itm/12v-LED-B...r-Alternator-warning-light-lamp-/200537741230

 

[geoff916]

Andy, What a great Idea! My son is an RAF avionics engineer and he has done same to his BMW.so he can get all kinds of meters! I do like meters / dials / lights etc.
Should be able to find space for a meter next to my Sat Nav, Camera, Neo speed camera unit,Heated grip switch, dual USB sockets. lol
Ill get one sorted straight away,
Cheers