Anyone know of a good workshop or individual that really knows their vfr400 stuff in Melbourne or VIC (Australia).

I am having an electrical issue with a recently-acquired race bike with a monkeyed-with-but-not-by-me wiring setup so ideally, they'd really know their onions and have experience with NC30 race bikes.

Or, if anyone here is up for it and are willing to help resolve it for money or beer or virgins in the afterlife, PM me.

Not getting it started on race days (sometimes) is sh*tting me off. I've missed two qualifying sessions this season because of it. (equals last on grid).

Oh, I am a moto-electrical nong, of the sub-amoeba-intellect variety and my spongy brain has a 'blind spot' with electricity.

Appreciated.

Greg. aka Moto-moron.

Can you be a little more specific with regard to the problem, what makes you thick it is electrical?

Hi there Magg, thanks for the reply.

I posted it here once before and, it being pretty weird, didn't get too much attention. I did get a pretty good 'check-list' response, but after checking stuff, I am still dry. It goes like this:

Sometimes when I start the bike it just seems like the battery is flat - it turns over slowly with a rurr-ruuuurr-ruuuuurrrrrr and then just seems like a dead battery - despite that it is fully charged. I bought a new battery and it did just precisely the same thing - so it sis not the battery then. I borrowed a mate's (charged) battery and it did the same also.

It seemed to manifest itself when the bike was not, but then last race meet when it was not hot it did the same thing.

I thought it only happened when hot, because the last couple of race meets it would do it when hot, then after 20 mins or so fire into life like a happy puppy - my guess was that it cooled down so the problem was a 'hot' problem.

But last race meet, it did the same then when cold. Engine not even warmed up. Then after a while, when still cold, it just started like it wanted to win a race. No flat battery sounds, it just jumped to life.

The only diagnostic thing I could add is the negative wire from the battery was *bloody* hot and smoked momentarily.

All advice appreciated.

Lots of heat & smoke usually means high resistance or lots of current. Do you have a multimeter, does the bike run well once started?

First suggestion would be to check the battery earth wire. Should be heavy gauge, at least 5mm diameter, and tightly bolted to the chassis. If you have a multimeter you can measure the voltage between the battery -ve terminal and the chassis, it should be less than 1 volt when you press the starter button.

Hey Greg,
Sounds like you've picked up a doozy of an electrical gremlin (I HATE elect problems!). I used to be the same as you when it came to all thing electrical, but since I've had my racebike I've totally stripped the wring loom, removed all unnecessary wiring, and the bike started straight away without any isses (I was more surprised than anyone!).

There's a wiring diagram located on this site somewhere that I used (there's 2 wiring diagrams, a complete street version and a stripped down race version). I followed the race version to a T and didn't have any problems.

I'm racing up at Broadford this weekend with Hartwell, so if you're racing I'll bring along the wiring diagrams for you to have? A mate of mine will be racing as well and he's pretty good when it comes to electrical stuff, so if you sweet-talk him a bit he'll have a look for you.

But regarding mechanics in Melbourne...I've only dealt with C&C Engineering and Profession Motorcycle Tuners (PMT...and shocking buiness name!), but it was only for mechanical isses, nothing electrical so I can't telll you whether they're any good in that area, however those guys know 400's really well so maybe have a chat to them.

C&C Engineering - 2/25 Aylward Avenue Thomastown VIC 3074 tel: (03) 9469 4774
PMT - 8a Rodd Rd, Airport West VIC 3042 tel: 0409 164 274

Good luck,
Josh

Thanks Josh, much appreciated. Thanks for the mech names. Re your electrical skills, you're way ahead of me for sure! I'm not with Hertwell, but next year will be. For the rest of this year I've got about two Ducati club days at PI, two Champions days, two more interclub and one VRR at PI - do that is about all the budget will handle I reckon. :-/

I've got a Haynes manual and it has the wiring diagram in it, but, doesn't mean all that much to me I am afraid! The wiring on this bike is not stock - it has already been stripped down to race trim (so I am told).

Re Magg above: The wire looks from the positive looks about 5mm, but it goes to a crummy well dodgy looking device on the left with a 30amp fuse below it. Manual says Starter Relay(?) Pics:

Battery:


Crummy well dodgy looking device:


And again:


battery connects to the rear right of dodgy thing, but not to the chassis. Wiring diagram says negative goes to earth, but on the bike the green (negative) just dissappears into a loom.

Re "If you have a multimeter you can measure the voltage between the battery -ve terminal and the chassis, it should be less than 1 volt when you press the starter button." I do have a multi-meter. So, with engine running do I hold one end of multi-meter to battery -ve and the other on the frame?

The lead from the +ve battery terminal to the starter relay should be ok. The wiring might be doggy but the starter relay is the OEM setup. The 30A fuse at the bottom is a spare, the real one is under the cover on the top of the starter relay and protects the wiring in the event of an overload.

The starter motor electrical circuit runs from the +ve battery terminal to the starter relay and then from the starter relay to the starter motor, all heavy gauge leads, the through the starter motor to the chassis and then through the chassis to a lead bolted to the chassis near the battery and through this lead to the battery terminal.

Where is your lead from the -ve battery terminal directly to the chassis? Using the earth wire in the loom is worse than bad. I am surprised that if this is the arrangement that the loom has not melted.

I suggest trying the lead from -ve battery terminal to chassis first and still no success we can look at making some voltage measurements.

Out of interest I assume that the OEM stator and rect/reg are fitted for charging the battery.

From the looks of the 2nd photo, the green earth wires seems to run towards the front of the bike (it's early in the morning so I thought I'd play Captain Obvious!). On both my bikes I have the earth wire running from the battery negative terminal to the frame directly in front of the battery (I suppose you'd call it the cross beam where the top of the shock mount bolts through (on an NC35 at least). I simple drilled and tapped an M6 hole into the frame, don't worry it's fairly solid, and bolted the earth wire there. Having had any problems with my charging system since so I'm hoping it's working fine.

If I was you I'd trace the green wire and see where it's attached. Maybe the connection to the frame is corrroded? Alll it may need is a good clean and she'll be apples :-)

Haynes manual page 5.3, picture 3.6, below the ignition coil, illustrates the OEM chassis battery lead connection. Big lug bolted to chassis next to the large bolt hole.

Josh: "I have the earth wire running from the battery negative terminal to the frame directly in front of the battery". None of that going on here. It does lead up to the front and I am not sure where it earths. Read on.

Magg: Yes, OEM stuff is there with starter motor. However, check this out:

No little man home here at all. Not even a loose wire dangling in behind there:


I see the big wire going from starter relay to start motor, but am stuffed if I can see anything else (it is 10pm and the garage is not that well lit) - will get a better look tomorrow:


I see this attached to frame on left side - the wire is green, but hey, it seems like the wires change colour along the way on this bike so I am not sure if this is -ve from battery. If it is, it has gone a long way to get there - possibly up to tacho etc then back.


I see this also, but it appears to come to come straight out of regulator:


Thanks for the help guys. Appreciated. I am learning a few things as well, and that is gold.