Reg/Rec eating itself?

Gents

apologies for the length of this but I'm trying to give as much info up front. If you need a cure for insomnia, read on.....



So I might be jumping the gun a bit and asking a leading question but I'm willing to follow up on alternative ideas/suggestions. I've been through the site looking at the topics on batteries, reg/rec failure, soft/dat messages and alternators and I think my reg/rec is failing. I suspect that the battery might now be a bit marginal (see below) but I don't want to replace it if the real problem is the reg/rec which is just going to wreck the next battery.


Over the last 600 – 700 miles (incl track time), I've had the following – but none of them consistently:

sluggish starting
5000 rpm on the clocks but normal real tick-over – went away next start, not repeated
fast flashing indicators - sometimes
battery light (low voltage) coming on –2 or 3 times, goes away shortly after
clock resets to 12:00

When I've charged the battery it starts fine – and I've been having the above issues when running with the headlight fuse removed as well as with the lights on.

I've visually inspected the wiring that I can see (after cleaning all the crap off from all the wiring in/on/around the battery box) and checked behind the headlight mask and all of the fuses and everything looks OK – no signs of wear/melting/scorching etc. and all the connectors, despite being covered in crap, have all cleaned up OK and look fine.

I've got a rubbish multi-meter (to the nearest volt, no decimals) and have got the following results:

Battery – straight after charging:

11/12 V, bike not running, ignition off
11 V, bike not running, ignition on, lights on
12/13 V, bike running, lights on – revving the bike doesn't appears to have any consistent effect but the voltage fluctuates around 12/13V
(when hitting the starter, the voltage drops to 8/9V for a split second at least once – I've only tried this a couple of times so I don't know if it happens all the time)

I've struggled with the Service Manual instructions but I think I've managed to test the generator coils (I'm assuming they mean the alternator – difference in terminology). The big, flat brown connector with the three yellow wires that sits next to the battery box cover is what I've tested. Disconnected it, tested the socket that goes to the alternator (as opposed to the reg/rec) for resistance. The multimeter beeps and gives pretty much the same reading for any pair of the 3 possible combinations of the 3 connectors in the block. This appears to be in line with what is expected – low resistance (beeps below 30 Ohms), no short, all combinations reading the same.

I thing I understand the section about checking for loss of current – but the multimeter I have only appears to be fable to check AC current.

The bike is bog standard '07 with a battery tender lead fitted and I've got a lead fitted for a heated vest – but haven't used it recently. I've been fairly careful with it so it is only on when out of town. I know these can ruin batteries.

So, thoughts please and has anyone tried the MOSFET reg/rec that has been mentioned on here – they only appear to be available from the US and look like they need some work to make them fit?

Are there other alternatives apart from the KTM version - which I'm assuming will eat itself eventually?

The KTM version appears to have been replaced with a different model number – is it actually any better/different?

Hey bro...
I haven't had any real problems...I thought I did but it was
my own dumb actions that caused it..Culprit actually WAS the battery..
Mine went bad and only had 1,000miles on the clock..
Didn't have a tendor..
It's a good idea to keep it on one...I got one right after spending $200
for a new battery...
Several guys have gone to Mosfet regulators..
Aside of the KTM regs being hard to get...
They are the reg of choice for other bikes too...
A guy I know rides a Buell 1125 and had his OEM reg replaced twice
within 5,000 miles..Bought it new...
Got a used Mosfet and was for a different bike even...
wired it up and hasn't had a problem since...
Hope it helps...
Search it on this site...
It's there...

Based on my experience, replace both the battery and reg/rec - you could replace one at a time but you will need to replace both sooner or later and if it is only one and not the other, you will have the spare ready when you need it.

Somehow mines made it to 50k without it going. I really should get one and keep it handy as its sure to go eventually.

Gents

I think, unfortunately, replacing both is the "sensible" way to go. Any suggestions from the rest of the gang? (I mean about the reg/rec - not laying tarmac....)

Does the Mosfet have the same fixing holes and centres as the OE reg/rec?

From your readings on your multi meter your battery is low.
This could be from the battery being shot or the regulator not charging it properly.
From your description it is the regulator. The coils on the generator seem fine and also they almost never crap out unless you have something comming loose and eats it.
Charge the battery properly and do the tests again. Also get your battery tested by a place who have a load tester, most places who sell batteries or garages have them. This will tell you the state of the battery.
After you know the battery condition and you did the charging test again the results will tell you if the regulator is fine or not.
keep us in the loop!

Gents

thanks for all the advice - new battery (same as Fuel, one of these lighter than air thingies, thanks matey) and standard reg/rec are on their way. I'll let you know the result when all in place.

As for the MOSFET alternative, I couldn't find anything over here and Electrex don't do one for the 990 motor (they do them for just about everything else) so decided to go for the standard rather than wait for delivery from the US. I'd be interested to see what they're like as there appears to be "kit" versions which require soldering etc but there is also a version sold under the name of Hot Shots which seem to be plug and play.

Cheers